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Tamworth Aeronautical Study /58 Final report

TTAAMMWWOORRTTHH Aeronautical Study

Client

Civil Aviation Safety Authority

To70 Aviation

PO Box 324

Nelson Bay

New South Wales 2315

Author

Juergen Ruppert

Adelaide, February 2010

Final Report

Change Record January 2010 Final report Final report JR January 2010 Final report Final report Review after comments from

CASA -JR February 2010 Final report Final report New ASIR data included February 2010 Final report Final report Review after CASA comments


Contents

1 Executive summary................................................................................................................................... 5

1.1 General information ................................................................................................................................................. 5

1.2 Findings ........................................................................................................................................................................ 6

2 Introduction ................................................................................................................................................ 8

2.1 Purpose......................................................................................................................................................................... 8

2.2 Scope ............................................................................................................................................................................. 8

2.3 Approach ..................................................................................................................................................................... 8

3 Tamworth Airport ................................................................................................................................... 10

3.1 Background ............................................................................................................................................................... 10

3.2 Airport location ........................................................................................................................................................ 10

3.3 Weather patterns .................................................................................................................................................... 11

3.4 Airport configuration ............................................................................................................................................. 11

3.5 Runway usage .......................................................................................................................................................... 12

3.6 Airspace and air traffic control ........................................................................................................................... 12

3.7 Airport users ............................................................................................................................................................. 13

3.7.1 Gliders, parachuting and model aircraft .................................................................................................... 13

3.7.2 Military traffic ...................................................................................................................................................... 14

3.8 Movements/passengers ....................................................................................................................................... 14

4 Stakeholder consultation .................................................................................................................... 15

4.1 Observations - General .......................................................................................................................................... 15

4.2 Observations- Passenger transport .................................................................................................................. 16

4.2.1 Main comments: ................................................................................................................................................ 16

4.2.2 Ancillary / general comments – Qantas Link ............................................................................................ 17

4.3 Observations - Airservices .................................................................................................................................... 17

5 Summary of incidents and accidents .............................................................................................. 18

5.1 Electronic Safety Incident Reports .................................................................................................................... 18

5.2 Aviation Safety Incident Reports (ASIRs) ......................................................................................................... 19

5.3 Summary .................................................................................................................................................................... 22

6 Fast time simulation and risk assessment ...................................................................................... 22

6.1 Methodology ............................................................................................................................................................ 22

6.2 Model inputs ............................................................................................................................................................. 23

6.3 Data selection ........................................................................................................................................................... 23

6.3.1 Static data ............................................................................................................................................................. 23

6.3.2 Flight data ............................................................................................................................................................ 23

6.3.3 Summary of movement data ......................................................................................................................... 23

6.3.4 Flight data synthesis – VFR activity .............................................................................................................. 24

6.3.5 Schedule validation .......................................................................................................................................... 25

6.4 Modelling rationale, assumptions and limitations ...................................................................................... 25

6.5 Modelling „intent‟ .................................................................................................................................................... 26

6.6 Conflict definition ................................................................................................................................................... 26

6.7 Simulation volume ................................................................................................................................................. 27

6.8 Flight procedures .................................................................................................................................................... 27

6.9 Limitations ................................................................................................................................................................. 29

6.10 Simulation process ................................................................................................................................................. 29


6.11 Observations made ................................................................................................................................................ 29

6.11.1 Conflict distribution in detail .................................................................................................................... 29

6.12 Airspace risk assessment ...................................................................................................................................... 36

6.12.1 Estimated traffic mix .................................................................................................................................... 37

6.12.2 Potential conflict pairs as found in the fast time simulations........................................................ 37

6.12.3 Compare airspace design and defence mechanisms with conflicts ........................................... 39

6.12.4 VFR traffic ........................................................................................................................................................ 39

6.12.5 Airservices‟ “Preliminary Risk Assessment of 10 Class D Towers”................................................ 41

6.12.6 Airspace surrounding Class D – Class C and Class E.......................................................................... 41

6.12.7 Airservices‟ “Risk Assessment Class E over Class D airspace” ......................................................... 41

6.12.8 Class C airspace above Tamworth Class D airspace .......................................................................... 42

7 Findings ..................................................................................................................................................... 44

Appendix 1 – Acronyms .......................................................................................................................................... 46

Appendix 2 – Australian airspace structure ..................................................................................................... 48

Appendix 4 – AirTOpTM ............................................................................................................................................ 52

Appendix 5 – Summary of Conflicts Observed ............................................................................................... 53

Appendix 6 – Regular Public Transport Questions ....................................................................................... 57

Figure 1: Tamworth area (source Google) ........................................................................................................................... 10

Figure 2: Tamworth Airport (source Google) ...................................................................................................................... 10

Figure 3 Airport layout Tamworth (source AIP Australia) ............................................................................................... 11

Figure 4: Lake Keepit Soaring Club location (source To70) ............................................................................................ 13

Figure 5: Lateral conflict criteria .............................................................................................................................................. 26

Figure 6: Tamworth Class "D" airspace (source To70) ...................................................................................................... 27

Figure 7 Tamworth Airport as implemented in AirTOp ™ (source AirTOp™) .......................................................... 28

Figure 8: Conflict Distribution by Time of Day – RWY 12 operations VFR only conflicts (source To70) .......... 31

Figure 9: Conflict Distribution by Time of Day – RWY 12 operations conflicts Involving IFR Flights (source

To70) ................................................................................................................................................................................................. 32

Figure 10: Conflict distribution by time of day – RWY 30 operations VFR only conflicts (source To70) ......... 33

Figure 11: Conflict distribution by time of day – RWY 30 operations conflict involving IFR flights (source

To70) ................................................................................................................................................................................................. 34

Figure 12 Distribution of conflicts with at least one IFR aircraft <500ft and < 0.5NM – RWY 12 Ops (source

AirTOp™/Google) ......................................................................................................................................................................... 35


AirTOp™/Google) ......................................................................................................................................................................... 36

Figure 14: Location of potential conflicts for RWY 12 ...................................................................................................... 40

Table 1: Number of cloudy days for Tamworth (source BOM) ...................................................................................... 11

Table 2: ESIRs July 2008 – June 2009 (source Airservices) .............................................................................................. 18

Table 3: ESIR classification July 2008 – June 2009 (source To70) ................................................................................. 18

Table 4: ASIRs July 2008 – June 2009 (source ATSB)) ....................................................................................................... 19

Table 5: ASIR classification July 2008 – June 2009 (source To70)................................................................................. 19

Table 6: ASIRs January 2004 – March 2009 (source ATSB) .............................................................................................. 20

Table 7: ASIR classification Jan 04 – Mar 09 (source ATSB) ............................................................................................. 21

Table 8: ASIR human errors Jan 04 – Mar 09 (source To70) ............................................................................................ 21

Table 9: BAE FTT running sheet summary ........................................................................................................................... 24


Table 10: Training flight activity mapping ........................................................................................................................... 24

Table 11 Conflict Severity Classification (source fast time simulation report)......................................................... 27

Table 12 Conflict distribution and separation category for RWY 12 (source To70) ............................................... 30

Table 13 Conflict distribution and separation category for RWY 30 (source To70) ............................................... 30

Table 14 Estimated traffic mix at Tamworth as at June 2009 ....................................................................................... 37

Table 15: Summary of characteristics for the closest conflicts observed during RWY 12 ops ........................... 37

Table 17: Distribution of conflicts (CPA <500ft and 0.5NM) by flight category and capacity –RWY 30

operations (source To70) ........................................................................................................................................................... 38

Table 18: Tamworth study results (source Airservices) ................................................................................................... 42


1 Executive summary

To70 Aviation has been commissioned by the Civil Aviation Safety Authority1 (CASA) to conduct this

aeronautical study in response to a requirement under the Australian Airspace Policy Statement. This

requirement includes the conduct of regular and ongoing reviews to meet CASA‟s obligations under

Section 13 of the Airspace Act. The Office of Airspace Regulation (OAR) within CASA employs a risk based

approach in determining which locations are studied.

The purpose of the study is to review the airspace classification above Tamworth Airport in New South

Wales. Particular emphasis is placed on the safety of regular public transport (RPT) operations.

This study was conducted within a due diligence framework. The work was conducted in three phases:

1. The concept and scope phase demonstrated understanding of the subject matter and was expressed

in terms of:

Airspace description;

Aerodrome and Infrastructure;

Stakeholder consultation (utilising questionnaires and telephone discussion of issues and

options), and

Site visit.

2. The identification and analysis phase commenced with the application of a fast time simulation base

case using the AirTOp™ simulation software to identify potential conflicts in the study airspace and

to compare the findings of the simulation with occurrences in the relevant airspace.

3. The evaluation phase employed a range of qualitative and quantitative risk assessment techniques to

establish effectiveness of precautionary options.

1.1 General information

Tamworth is situated on the New England Highway approximately 500km north of Sydney and 600km

south of Brisbane. Tamworth Regional Airport lies 9.4km west from the city centre of Tamworth.

Tamworth Airport has four runways; two sealed and two grassed clay runways. The two sealed runways

are parallel and aligned 12/30. Navigation facilities such as VOR2, NDB3, ILS4 and DME5 are located at the

airport.

An aerodrome and approach control service is provided by Airservices Australia (Airservices) from

Tamworth control tower from 07:00 to 20:15 local time Monday to Friday and 08:00 to 15:15 local time on

Saturday and Sunday in controlled airspace from the surface to 8500 feet (ft) above mean sea level

(AMSL). Within these hours, the controlled airspace up to 4500ft AMSL is Class D airspace. Controlled

airspace between 4500ft AMSL and 8500ft AMSL is Class C airspace. Brisbane Air Traffic Services Centre

(ATSC) provides an en-route service in the Class C airspace above 8500ft AMSL.

1 A full list of acronyms is attached in Appendix 1

2 VOR = Very High Frequency Omni-directional Radio Range

3 NDB = Non-Directional Beacon

4 ILS = Instrument Landing System

5 DME = Distance Measuring Equipment


Outside the control tower opening hours (tower hours), Tamworth Class D and C airspace (8500ft AMSL

and below) are reclassified Class G. Common Traffic Advisory Frequency (Radio) (CTAF(R)) procedures

apply within the vicinity of the airport. Airservices provides a Class G airspace service from the Brisbane

ATSC.

The airport is the home base of British Aerospace Flight Training Tamworth (BAE FTT), which carries out

ab-initio pilot training for the Royal Australian Air Force (RAAF) and the Singapore Air Force using Pacific

Aerospace CT4 and Mudry CAP10 aircraft. The airport has regular services to various destinations operated

by Qantas Link and Brindabella Airlines. It is also the Northern base of the Hunter Region Westpac Life

Saver Rescue Helicopter Service.

1.2 Findings

Both fast time simulation and consultation with the airspace users indicate that the current airspace

classification allows for the safe conduct of all operations, including RPT.

The study revealed:

The results of the fast time simulation of the airspace around Tamworth lead to the conclusion that

the Class D airspace with the relevant procedures applied will provide sufficient defences against the

most severe potential conflicts identified;

The dimensions of Class D and Class C airspace around and above Tamworth are deemed to be

adequate by the airspace users and air traffic control. The results of the fast time simulation did not

provide any other evidence to the contrary and no documentation was found during the study

stating the opposite;

All airspace users consulted indicated that the airspace classification utilised is suitable for its current

use;

Approximately 10 percent of all movements at Tamworth are conducted outside of the tower hours

and are therefore operating under CTAF(R) procedures. The main contributor is BAE FTT with night

circuit training on the main runway;

During the week, when BAE FTT night flight training takes place, there is one RPT night flight

operating after the closure of the control tower. BAE FTT will try to avoid night circuit training until

the RPT aircraft has landed whenever possible in order to minimise any interference with RPT

operations;

Although the fast time simulation found some potential conflicts for this time of the day, the

interviews with BAE FTT, Airservices and the airport operator as well as the analysis of air safety

incident report (ASIR) and electronic safety incident report (ESIR) data showed no incidents between

RPT and training aircraft performing night circuits;

BAE FTT has set up a runway caravan to assist the circuit training with providing additional situational

awareness to the pilots in the traffic circuit. This could be seen as an additional risk mitigator;

ASIR and ESIR data indicate that failure to observe Air Traffic Control (ATC) instructions and violation

of controlled airspace (VCA) are the most observed airspace related concerns reported. These

incidents are mainly related to human error such as misinterpreting ATC instructions and cannot

directly be linked with the design and class of airspace provided at Tamworth;

Less than one in two hundred flights in the period from July 2008 to June 2009 relate to reported

ESIR incidents such as failure to comply with instructions or procedures (violation of controlled

airspace, failure to comply ATC instructions or procedures and runway incursion). Most of the


incidents were related to (student) pilot errors or misinterpretation of ATC instructions. An analysis of

the ASIR reports of the last 5 years showed the same result.

This leads to the conclusion that the airspace design and classification of Tamworth can be

considered to be appropriate for its use.

Based on this study, To70 recommends that:

CASA should review the ESIR and ASIR incidents categorised as failure to comply with instructions or

procedures (violation of controlled airspace, failure to comply ATC instructions or procedures and

runway incursion). About 40 percent of all reported incidents for Tamworth can be related to human

error such as violation of controlled airspace and breakdown of separation/coordination, mainly

related to pilot error or misinterpretation of ATC instructions. It is recommended That CASA should

review these incidents and develop training material to minimise these incidents;

CASA should continue monitoring the airspace around Tamworth with particular focus on changes in

types and numbers of movements outside the tower hours and changes in Instrument Flight Rule

(IFR) and Visual Flight Rule (VFR) numbers and training activities;

CASA should conduct pilot education to familiarise every airspace user with CTAF(R) procedures

taking into account the proposed changes to CAR 166 and potential training and education issues

resulting from the changes

Class C airspace above Tamworth Class D airspace should be maintained unless a new aeronautical

study using an airspace risk analysis methodology and cost benefit analysis can prove significant

benefits for Class E airspace.

It is recommended that the OAR maintain a watch of activity at Tamworth aerodrome during the bi-

annual review of movement data, and, if total aircraft movements significantly increase, or after five

years, whichever occurs first, further airspace review or an aeronautical study will be conducted to

reassess the risk to RPT operations.


2 Introduction

To70 Aviation has been commissioned by CASA to conduct an aeronautical study in response to a

requirement under the 2007 Australian Airspace Policy Statement6 (AAPS 2007). This requirement

includes the conduct of regular and ongoing reviews to meet CASA‟s obligations under Section 13 of the

Airspace Act. The study reviews the airspace classification above Tamworth Airport in New South Wales.

Particular emphasis is placed on the safety of regular public transport (RPT) operations.

The OAR within CASA is responsible for the regulation of Australian-administered airspace in accordance

with section 11 of the Airspace Act 2007 (Act). Section 12 of the Act requires CASA to foster both the

efficient use of Australian-administered airspace and equitable access to that airspace for all users. CASA

must also take into account the capacity of Australian-administered airspace to accommodate changes to

its use.

In line with the International Civil Aviation Organization (ICAO) Annex 11 and as described in the AAPS,

Australian airspace is classified as Class A, C, D, E and G depending on the level of service required to

manage traffic safely and effectively. The classification determines the category of flights permitted and

the level of air traffic services (ATS) provided. Appendix 2 provides details of the classes of airspace used in

Australia.

Airspace around uncontrolled aerodromes in Australia is subject to either CTAF or designated CTAF (radio

required) (CTAF(R)) procedures; the latter requiring all aircraft operating at or in the vicinity of the airport

to be equipped with a serviceable Very High Frequency (VHF) radio.

2.1 Purpose

The purpose of this study was to provide CASA with an assessment of risk in terms of the potential for mid

air collision between aircraft operating in the airspace in the vicinity of Tamworth Airport. The subject

airspace is currently classified „D‟ during the hours of the ATC service provided from Tamworth tower. The

study forms part of the OAR work program as required by the Act. Particular emphasis is placed on the

safety of RPT operations to ensure that all reasonable precautionary measures are in place.

2.2 Scope

The scope of the study includes:

Identification and consultation with stakeholders to gather necessary data and information related to

airspace issues around Tamworth Aerodrome. This includes a site visit to Tamworth and consultation

with RPT operators, other operators, ATC and the airport operator;

Conduct of a fast time simulation to identify potential conflicts;

Analysis of ESIR and ASIR data.

This study does not examine airport facilities and infrastructure issues.

2.3 Approach

To70 followed the subsequent approach:

6 At the time of the compilation of this study the AAPS has been subject to review and re-issue. For the

purpose of this study all references relate to the 2007 AAPS.

http://www.comlaw.gov.au/comlaw/management.nsf/lookupindexpagesbyid/IP200730484?OpenDocument


Analysis of current traffic levels and mix of aircraft operations within the existing airspace in relation

to the level of services provided;

Identifying any threats to the operations, focussing as a priority on the safety and protection of RPT

services;

Carrying out a risk assessment of the current airspace environment facilitated by the results of a fast

time simulation in form of a list of potential conflicts in the airspace;

Investigating the appropriateness of the current airspace classification with particular reference to

issues of access to the airspace and likely or forecast changes to the current traffic levels and mix of

aircraft operations through stakeholder consultation;

Identifying appropriate and feasible risk mitigations to threats as identified;

Reviewing extant Aeronautical Information Publication (AIP) entries for applicability;

Ensuring that the issues are passed onto the relative stakeholder group for their consideration;

Analysis of ASIR data provided by the Australian Transport Safety Bureau (ATSB) and ESIR data

supplied by Airservices .


3 Tamworth Airport

3.1 Background

Figure 1 shows the geographic location of Tamworth

Figure 1: Tamworth area (source Google)

Tamworth is situated on the New England Highway approximately 500km north of Sydney and 600km

south of Brisbane.

3.2 Airport location

Tamworth Regional Airport is 9.4km west from the centre of the city of Tamworth‟s Central Business

District. It is on latitude 31 04‟07" south and longitude 150 50‟44" east and is located at an elevation of

1,334 feet. The airport is in flat open country with no hills closer than 11km.

The airport is the home base of BAE FTT, which carries out ab-initio pilot training for the RAAF and the

Singapore Air Force using CT4 and CAP10 aircraft. It is a significant regional airport with passenger

services to various destinations operated by Qantas Link and Brindabella Airlines. It is also the northern

base of the Hunter Region Westpac Life Saver Rescue Helicopter Service. Figure 2 shows the airport layout.

Figure 2: Tamworth Airport (source Google)


3.3 Weather patterns

The average cloud cover was estimated by the Bureau of Meteorology (BOM) and is summarised in the

column graph below.

Table 1: Number of cloudy days for Tamworth (source BOM)

The mean 09:00 local time wind speed is 11.2km/hour and 16.2km/hour at 15:00 local time. The main

wind direction is south east before 09:00 local time and then changing to west. This also explains why

runway (RWY) 30 is used more than 50 percent of the time.

Tamworth Airport has only been closed due to weather effects (fog, storms, very heavy rain, etc.) thirteen

times in ten years. Tamworth has an average of 273 fine days a year, however it also has a reasonable

rainfall of nearly 690mm (27 inches) a year. Flight training and other activities can be conducted all year

round.

3.4 Airport configuration

The airport layout including runway and taxiway configuration at Tamworth is reproduced in Figure 3

Airport layout Tamworth

Figure 3 Airport layout Tamworth (source AIP Australia)


Tamworth Airport has four runways; two sealed and two grassed clay runways. The two sealed runways

are parallel and aligned 12/30. The larger of these runways (12L/30R) is 2200 metres (7218 feet) long, 45

metres wide and is grooved bitumen sealed. Its ICAO Pavement Classification Number is 35. It is capable

of taking aircraft up to the size of a Boeing B737. Concessions and approvals for larger aircraft have been

granted from time to time. The second sealed runway (12R/30L) is 1110 metres long and 18 metres wide.

It is designed for an aircraft with a maximum all-up weight of 5700 kg and is predominantly used by BAE

FTT operations (e.g. CT4 aircraft). The two grassed clay runways both cross RWY 12L/30R. Runway 18/36 is

1021 metres (3350 feet) long and 30 metres wide while runway 06/24 is 841 metres (2759 feet) long and

30 metres wide. Both runways are maintained although used much less frequently than the sealed

runways.

An Instrument Landing System (ILS) approach is only available for RWY 30R. There are two Global

Positioning System (GPS) approaches published for RWY 12L and RWY 30R. There are also non precision

instrument approaches serviced by VOR, NDB and DME. RWY 12L/30R is the only runway with a lighting

system.

3.5 Runway usage

All IFR movements are limited to RWY 12L/30R, while the southern runway (12R/30L) is used

predominantly by BAE FTT CT4 aircraft. Most other aircraft including the BAE FTT CAP10 aircraft use the

northern runway (12L/30R). The grass runways are used only occasionally (once or twice per week).

Airfield operations are in RWY30 direction for more than 50 percent of ATC operating hours with RWY12

direction most typically used in the mornings up until about 10:00am local time.

3.6 Airspace and air traffic control

Tamworth tower is the only Class D tower that has two independent Aerodrome Control (ADC)

frequencies to accommodate the combined training and normal operations at the field. It also has a

combined Surface Movement Control (SMC) / Airways Clearance Delivery (ACD) frequency. One ADC

frequency is used for control of aircraft and vehicle movements to and from RWY 12L/30R and the other

frequency is used for control of aircraft and vehicle movements to and from RWY 12R/30L.

An aerodrome and approach control service is provided from Tamworth control tower from 07:00 to 20:15

local time Monday to Friday and 08:00 to 15:15 local time on Saturday and Sunday in controlled airspace

from the surface to 8500ft AMSL. During the opening hours of the Control tower, the controlled airspace

up to 4500ft AMSL is Class D while controlled airspace between 4500ft AMSL and 8500ft AMSL is Class C.

Brisbane ATSC provides an en-route service in the Class C airspace above 8500ft AMSL.

Outside the tower hours, Tamworth Class D and C airspace 8500ft AMSL and below are reclassified Class G

and CTAF(R) procedures apply within the vicinity of the airport. During this time a Class G service from the

Brisbane ATSC is provided by Airservices..

Civil Aviation Safety Regulation Part 173 (CASR Part 173) requires instrument approach procedures to

controlled aerodromes to be in controlled airspace (CTA) Class C, D, and E.

The following instrument approaches are published for use at Tamworth:

DME/GPS Arrival;

ILS or Localiser (LOC) Approach RWY 30R;


VOR RWY 12L;

VOR RWY 30R;

NDB A or VOR A;

RNAV7 (GNSS8) RWY 12L;

RNAV (GNSS) RWY 30R.

Circling approaches are restricted for CAT C and D aircraft to a 4NM radius.

3.7 Airport users

The following major airport users have been identified at Tamworth:

Qantas Link;

Brindabella Airlines;

BAE FTT;

Country Capital Flight Centre;

Hunter Region Westpac Life Saver Rescue Helicopter Service.

These users are operating aircraft such as Bombardier Dash 8 (DHC-8), Fairchild Metro III, a variety of

general aviation types, both single and multi engine aircraft, as well as helicopter.

3.7.1 Gliders, parachuting and model aircraft

Lake Keepit Soaring Club (ICAO designator LKSC) conducts glider flying in the vicinity of Tamworth. The

glider site is situated at Lake Keepit approximately 20NM northwest of Tamworth Airport. Interviews with

stakeholders at Tamworth indicated that the club has established lines of communications with all

relevant parties at Tamworth Airport (e.g. ATC, RPT operators, BAE FTT and airport operator). All

competitions are coordinated with these parties and rules and regulations are enforced to avoid

controlled airspace. As a general rule, all gliders stay outside of controlled airspace. Figure 4 shows the

location of Lake Keepit in relation to the Tamworth airspace.

Figure 4: Lake Keepit Soaring Club location (source To70)

7 RNAV = Area Navigation

8 GNSS = Global Navigation Satellite System


The Tamworth Area Radio Model Aircraft Club recently moved to a new location near Somerset and now

operates outside of controlled airspace. Parachuting does not take place at Tamworth.

3.7.2 Military traffic

The traffic statistics show 338 arrivals with 150 traffic circuits and 323 departures for military aircraft over a

period of 12 months. This equals less than one flight per day and less than one percent of the total aircraft

movements on average. Therefore, military traffic does not play a significant role in this study.

3.8 Movements/passengers

For the 12 month period ending June 2009, Tamworth had more than 90,000 movements (i.e.

approximately 245 per day) carrying approximately 117,000 passengers during the opening hours of the

control tower. There are approximately 11,000 RPT operations which are provided by Qantas Link using

DHC-8 aircraft, and Brindabella Airlines using Metro III aircraft.

Eighty-eight percent of aircraft movements are VFR which are mainly associated with local flying training.

The BAE FTT is contracted to the RAAF and the Republic of Singapore Air Force to conduct flight screening

as well as basic flight training. BAE FTT currently has 18 aircraft operational each day with each aircraft

conducting approximately 4-5 daily sorties.

According to the information provided by the airport operator, an additional 9,000 movements (an

additional 10 percent of movements recorded during the tower hours) can be estimated for operations

after the closure of the control tower.


4 Stakeholder consultation

To70 identified the following major stakeholders operating at Tamworth Airport:

1. Airservices;

2. Qantas Link;

3. Brindabella Airlines;

4. BAE FTT;

5. Country Capital Flight Centre;

6. Hunter Region Westpac Life Saver Rescue Helicopter Service.

To70 staff conducted two site visits to Tamworth Airport to gather relevant operational information.

During this visit discussions were held with Qantas Link, BAE FTT, the airport operator and Airservices staff.

Brindabella Airlines staff were not available for an interview. Telephonic conversations were held and a

questionnaire was sent to Country Capital Flight Centre – no response had been received at the

conclusion of this study.

In addition, CASA has sent a questionnaire to Qantas Link and BAE FTT. A copy of the summary of airspace

user responses can be found in Appendix 6.

4.1 Observations - General

The following observations were made during the site visit:

BAE FTT appears to have a well organised flight training regime. All sorties are planned well in

advance. Safety management systems are in place to learn from incidents. The flying school provided

detailed information about its training activities and flight profiles9;

Lines of communication are established between all major airport users (airport operator, BAE FTT,

Airservices) in order to coordinate and monitor activities. Whenever there is an issue outside of

normal operations the relevant parties will discuss and solve the issue;

There are also local agreements in place (e.g. letter of agreement between BAE FTT and Airservices)

to describe procedures with ATC and RPT airlines;

Effective traffic management measures have been implemented to provide appropriate priority rules

for IFR traffic amongst the density of VFR training aircraft. BAE FTT has set up a runway caravan along

the side of the runway to provide additional situational awareness for the student pilots when

commencing traffic circuits. This also applies for night circuits when the control tower is closed;

Most of the training aircraft are using the smaller runway, 12R/30L, for their operations. The main

runway, 12L/30R, is only used by BAE FTT for flight screening10 and IFR training flights. BAE FTT also

uses RWY 12L/30R for night circuit training as it is the only runway equipped with a lighting system;

The Westpac Helicopter conducts regular rescue missions. The helicopter departs from a mobile

platform in front of the BAE FTT hangar and proceeds to the hospital in Tamworth to pick up a

medical team before continuing its mission. All movements are kept well clear of other activities at

the airport and do not interfere with other traffic;

Due to the new location, the model flying activities do not have any impact on aircraft operations at

Tamworth;

9 This information was used to create the fast time simulation model and to perform the airspace risk assessment in chapter 7.

10 Flight Screening Program is a flying-based assessment of potential candidates conducted at the BAE Systems Training

Academy at Tamworth


Interviews with stakeholders at Tamworth indicated that The Lake Keepit Soaring Club is well

organised and lines of communications are established with all relevant parties at Tamworth Airport

(e.g. ATC, RPT operators, BAE FTT and airport operator). All competitions are coordinated with these

parties and rules and regulations are enforced to avoid controlled airspace. According to all other

airspace users and ATC, there are no issues related with glider operations;

The local aero club operates infrequently with an average of less than 5 to 6 movements per week;

Country Capital Flight Centre has charter and training flights. Currently they are conducting circuit

training once or twice a week. The company has restricted it‟s training to RWY 12L /30R and does not

use the smaller runway, 12R/30L, on any occasion. Country Capital Flight Centre also recently

established its own training area northeast of Tamworth and does not interfere with BAE FTT‟s flight

training sorties;

All stakeholders agree that there are no identified issues regarding transponder use at Tamworth;

The airport operator stated that an additional 10 percent of the number of aircraft movements

recorded during the Control Tower (TWR) opening hours can be added for flights outside the tower

hours. These movements were predominantly VFR night circuit training flights conducted by BAE

FTT.

4.2 Observations- Passenger transport

RPT operations are conducted by Qantas Link and Brindabella Airlines. In order to consider the concerns

of these airlines, representatives of the airlines were asked to provide feedback about airspace issues at

Tamworth.

4.2.1 Main comments:

In general there are no identified issues with the airspace as classified at and above Tamworth

Airport;

No issues with glider or parachute activities are on record;

The interaction between the airlines and the Lake Keepit Soaring Club is considered as excellent by

all stakeholders interviewed. All major activities are coordinated between the parties and there are

no known issues in regards of glider operations in the vicinity of Tamworth Airport;

The interviews with RPT operators and BAE FTT indicated that there were no issues with transponder

equipage and use that were of concern;

Qantas Link operated return flights from Sydney via Tamworth to Armidale in the previous years.

Immediately after departure from Tamworth, these flights went into Class G airspace en route to

Armidale. On the return flight, it was sometimes difficult to obtain a clearance into controlled

airspace due to frequency congestion. This led to several violations of controlled airspace. Qantas

Link is now operating direct flights from Sydney to Armidale; therefore, there are no more issues

comparative to the ones described above;

Qantas Link operates one flight in the morning (at 06:00 local) and one flight in the evening on

weekends (at 20:30 local) outside of the TWR opening hours. These flights operate under CTAF(R) and

no issues with other airspace users are recorded in the airlines safety management system. The

general observation was that the circuit training flights do not start their sorties until the RPT aircraft

has cleared the area. The feedback received from BAE FTT supports this statement.


4.2.2 Ancillary / general comments – Qantas Link

In addition to the Tamworth specific comments, Qantas Link made the following comments which are

applicable in a more generic form to all Qantas Link destinations:

“BOM weather information should be available 24hours / 7days and on a VHF frequency audible from

up to 80NM (highest Top of Descent (TOD). This does not preclude Automatic Terminal Information

Service (ATIS) at tower locations, but if and when the TWR is closed, the BOM info must be able to be

switched to a reliable VHF outlet. An arrangement similar to that of Coffs Harbour where the weather

information is not available in flight after tower hours is considered unacceptable”;

“There is a strong preference for CTAF / Aerodrome Frequency Response Unit (AFRU) / Pilot activated

lighting (PAL) lighting outside TWR operating hours. To be able to confirm the lighting status on the

CTAF is a significant safety enhancement for non towered regional aviation”;

“RNAV (GNSS) approaches should be runway aligned from both directions of the primary runway set-

up. This best ensures the crew are not operationally forced into a low level circling approach in poor

weather. This will become even more significant as terrestrial navigation aids are gradually removed”.

4.3 Observations - Airservices

Airservices control tower staff was interviewed during the site visit and the information provided was

included in the simulation to build the simulation model.

The information gathered included, but was not limited to:

Airport layout;

Airport operations;

ATC procedures;

Special occurrences;

Traffic behaviour;

Traffic pattern;

Runway usage;

Flight training;

Other issues.

No major issues concerning operations at Tamworth were raised.


5 Summary of incidents and accidents

5.1 Electronic Safety Incident Reports

During the period July 2008 to June 2009, 89 ESIRs as shown below in table 2 were recorded by Airservices

for the airspace surrounding Tamworth.

Table 2: ESIRs July 2008 – June 2009 (source Airservices)

Of the reported incidents, To70 classified seven groups related to ATC issues as shown in table 3.

Table 3: ESIR classification July 2008 – June 2009 (source To70)

Forty seven of the 89 incidents relate to failure to comply with instructions or procedures (violation of

controlled airspace, failure to comply ATC instructions or procedures and runway incursion). These

incidents mainly occur when aircraft were trying to enter controlled airspace. While this represents over

50percent of all incidents, it should be noted that 89 reported incidents equates to 0.1percent of the total

movements into Tamworth.


5.2 Aviation Safety Incident Reports (ASIRs)

All accidents and incidents involving Australian registered aircraft, or foreign aircraft in Australian airspace

must be reported to the Australian Transport Safety Bureau (ATSB). The ATSB maintains its own database

(Occurrence Analysis and Safety Information System) in which all reports assessed by the ATSB as an

accident, incident or serious incident are recorded. Each individual report is known as an Air Safety

Incident Report (ASIR) and for identification purposes is allocated its own serial number.

During the period July 2008 to June 2009, 70 Aviation Safety Incident Reports (ASIR) occurred in the

airspace surrounding Tamworth as shown in table 4. During this period there were no serious incidents or

accidents reported.

Table 4: ASIRs July 2008 – June 2009 (source ATSB))

30 of the 70 incidents relate to failure to comply with instructions or procedures (operational non-

compliance, airspace incursion, etc). To70 classified the types of incidents as shown in table5.

Table 5: ASIR classification July 2008 – June 2009 (source To70)


Bird strike, power plant issues and systems failure were the most common categories in the raw data.

Further analysis of the ASIR data showed that many incidents were reported under an inappropriate or

ambiguous category. After closer examination, it was found that one of the larger groups of incident

categories is related to human error (violation of controlled airspace, failure to comply ATC instructions or

procedures, etc.). Human error alone accounts for approximately 43percent of all the incidents recorded

for the period of July 2008 to June 2009 at Tamworth Airport. The category with the highest human error

related incidents is operational non-compliance, with 14 incidents happening from failing to comply with

ATC instructions and commencing take-off and landing without clearances.

Only 3 incidents in the period from July 2008 to June 2009 were related to RPT aircraft with one

operational non compliance (the aircraft descended further than cleared), one incident at the edge of

controlled airspace at 8500ft AMSL and one potential conflict due to loss of ATC situational awareness. All

incidents involved aircraft operating under VFR.

Further analysis of the detailed ASIR reports indicates no direct relation between the incidents and

airspace (design and classification) related issues. Most of the incidents were related to pilot (student)

error or misinterpretation of ATC instructions.

Due to the relatively small number of recorded incidents the study team decided to extend the use of

available records and evaluate ASIR entries for the period from January 2004 to March 2009 in addition to

the above data to validate the findings. During this period there has been a total of 405 aviation related

accidents at Tamworth Airport and in the surrounding airspace s shown in table 6.

Table 6: ASIRs January 2004 – March 2009 (source ATSB)

During this period, 91 bird and animal strikes occurred, while power plant and system problems together

produced 108 incidents. Approximately 131 recorded incidents happened as a result of human error. A

number of events were related to ATC with a result of breakdown of separation/coordination and

violation of controlled airspace. Twelve incidents were related to a breakdown of aircraft separation. A

closer analysis showed that violation of controlled airspace and runway incursions were also reported in

this category. After applying another filter, the number of separation related incidents was reduced to 13.

Four of these incidents were related to ATC with one incident in Class C airspace above Tamworth Class D.

All incidents were corrected immediately after detection. The other 9 incidents were related to pilot error

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(e.g. pilot lost sight of other aircraft or pilot did not follow instructions). Table 7 shows the top 12 incident

categories.

Table 7: ASIR classification Jan 04 – Mar 09 (source ATSB)

As already pointed out above, bird strike, power plant issues and systems failure were the most common

categories in the raw data. Human error alone accounts for approximately 38percent of all the incidents

recorded for the period of 2004 to 2009 at Tamworth Airport. This also confirms the findings for the period

from July 2008 to July 09. To70 classified the top 15 human error factors as shown in table 8.

Table 8: ASIR human errors Jan 04 – Mar 09 (source To70)

0 20 40 60 80 100

Procedural error

Warning Device

Aircraft Control

Ground Operations

Airframe

Aircraft Separation

Airspace Incursion

Significant event

Operational Non-compliance

Systems

Powerplant/propulsion

Bird/animal strike

Incidents by category (top 12)

0 10 20 30 40 50 60

MiscellaneousCommunications

Fuel relatedRegulations and SOPs

Weather/environmentBreakdown of Coordination

Information errorNavigation/flight planning

Procedural errorAircraft Control

Ground OperationsAircraft Separation

Significant eventAirspace Incursion

Operational Non-compliance

Incidents as a result of Human Error


5.3 Summary

Due to the lack of information provided in the ESIR and ASIR records, it is not possible to analyse the

incidents in more detail. Incidents are sometimes recorded twice by both aircraft involved creating an

individual record for the same incident. Entries are sometimes made in a different category, e.g. airspace

violations are recorded as breakdown of separation, etc. This will at least partially explain the difference in

numbers in ESIR and ASIR records.

Bird strike, power plant issues and systems failure were the most common categories in the raw data.

An analysis of the ESIR and ASIR data in the time between July08 and June09 showed no records of any

transponder related incidents

It was found that one of the larger groups of incident categories is related to human error (violation of

controlled airspace, failure to comply ATC instructions or procedures, etc.).

Human error alone accounts for the majority of all the incidents recorded for the period of July 2008 to

June 2009 at Tamworth Airport. The category with the highest human error related incidents is

operational non-compliance, with incidents happening from failing to comply with ATC instructions and

commencing take-off and landing without clearances.

No direct relation between the incidents and airspace (design and classification) related issues were

found. Most of the incidents were related to pilot (student) error or misinterpretation of ATC instructions.

6 Fast time simulation and risk assessment

6.1 Methodology

Fast time simulation modelling and analysis of the traffic movement data was carried out using AirTOp™.

A more detailed explanation of AirTOp™ and its application and results were provided in the Tamworth

“Airspace study to collect collision pairs for assessment11”, further referred to as fast time simulation report

in this document.

The fast time simulation model was constructed to replicate the airport and airspace configuration at

Tamworth Airport. The model was then run using flight data supplied by the client collected from one

month (31 days) of operations in the airspace concerned as well as supplementary data collected during a

field visit conducted by To70. The output from the fast time simulation system facilitates the identification

of aircraft pairs where the minimum separation falls below a specified level. In addition to the category

and flight path of the aircraft constituting each pair, these conflicts are identified by severity, location and

time of day and aircraft category.

The identified conflicts were then categorised and analysed for their contribution to the risk in the study

airspace.

11 The Tamworth “Airspace study to collect collision pairs for assessment” is a CASA internal report

summarising the results of a fast time simulation conducted by To70 on behalf of CASA OAR.


6.2 Model inputs

As well as the aircraft performance data supplied within the AirTOp™ package, there are two categories of

data input to the fast time simulation process:

Static data, made up of the airport and airspace configuration and representations of the basic

procedures used by arriving and departing aircraft,

Traffic data representing the intent of aircraft operating to, from and in the vicinity of the subject

airport.

6.3 Data selection

6.3.1 Static data

Airspace information was obtained from the Aeronautical Information Publication (AIP) Australia

Designated Airspace Handbook (DAH)

http://www.airservicesaustralia.com/publications/current/dah/toc.pdf;

Terminal area procedures definitions were obtained from AIP (Australia) Departure and Approach

Procedures (DAP)

http://www.airservicesaustralia.com/publications/current/dap/AeroProcChartsTOC.htm;

Data on aerodrome configuration and local procedures was obtained from

http://www.airservicesaustralia.com/publications/current/ersa/FAC_YSTW_4-Jun-2009.pdf;

A visit to Tamworth control tower was conducted to gather data on local traffic management

practices and behaviours;

Additional Waypoint data was provided by Airservices.

Specific performance data for the BAE FTT CT4 aircraft was obtained from BAE FTT staff as a follow up to

the site visit.

6.3.2 Flight data

A principal source of flight data used in the fast time simulation study was the file YSTW_feb09_1.txt

supplied by the OAR. This file contained in excess of 302,000 flight data records covering May 2009 and

had been extracted from the Airservices from their Operational Data Warehouse (ODW). Since this data is

limited to records of IFR flights and those VFR flights using airspace under the control of the Brisbane

ATSC, it was necessary to synthesise flight plan data on local VFR flights from control tower records

including daily running sheets prepared by BAE FTT flight operations staff.

6.3.3 Summary of movement data

An Airservices summary of airport operator passenger movements is given in Appendix 3. Aircraft

movement data and passenger movements in charter or private aircraft are not recorded by the airport

operator. The total passenger numbers recorded by the airport operator each year only represents those

passengers that transit through the airport on RPT, this data being provided by the airlines on a monthly

basis.

Therefore the airport operator passenger movement data is statistically very similar to the Bureau of

Infrastructure, Transport and Regional Economics (BITRE) data recorded for the same periods.

http://www.airservicesaustralia.com/publications/current/dah/toc.pdf

http://www.airservicesaustralia.com/publications/current/dap/AeroProcChartsTOC.htm


6.3.4 Flight data synthesis – VFR activity

A site visit to Tamworth control tower and extensive observation of operations and discussions with

Tamworth ATC Subject Matter Experts (Airservices tower staff) was carried out by the author to capture

data for the further enhancement of the VFR traffic content of the model. Nine BAE FTT Academy running

sheets were selected at random and copied from control tower records. Data from these sheets is

summarised in Table 9:

Date DOW Total Sorties Estimated

circuits

Estimated

instrument

approaches

Estimated

runway

movements

Movements

after 1800

6/11/08 Thur 58 78 12 148 34

10/11/08 Mon 77 80 10 167 30

31/3/09 Tues 67 106 10 183 0

7/4/09 Tues 64 64 6 134 0

12/6/09 Thur 66 172 2 240 34

19/6/09 Thur 65 132 10 207 34

11/8/09 Tues 67 76 8 151 26

12/8/09 Wed 50 98 0 148 28

13/8/09 Thur 72 204 4 280 0

Table 9: BAE FTT running sheet summary

Based on typical weekly operating patterns, the activity levels from these sheets were mapped onto the

31 days of IFR activity as set out in Table 10.

Date Day of Week Days in Simulation

10/11/08 Mon 3, 10, 17, 24

31/3/09 Tues 4, 11, 18, 25

12/8/09 Wed 5, 12, 19, 26

13/8/09 Thur 6, 13, 20, 27

7/4/09 Tues 7, 14, 21, 28

Table 10: Training flight activity mapping

The following classes of training flights were identified from the running sheets and discussion with tower

staff:

Temporary Reserves Area (TRA) flights

Circuit training flights (CCTS)

TRA and CCTS

VFR navigation exercises (V-NAV)

IFR NAV

TRA and VOR approach

Local IFR training with approaches

Flight plans were synthesised for each of the activities identified and then cloned in accordance with the

running sheets in Table 9 to arrive at a training schedule for each of five days of typical BAE FTT activity.


6.3.5 Schedule validation

The resultant schedules cover a typical month of operations compiled as follows:

31 separate and unique days of IFR and flight planned VFR operations including information available

from ATC tower running sheets for weekends. Each day covers the period 00:00 UTC12 to 23:59 UTC

corresponding to 10:00 Eastern Standard Time (EST) to 09:59 EST;

5 separate and unique days (Monday thru Friday) of local VFR operations (BAE FTT Academy

operations). These were repeated pro rata over the 31 days with estimated times of departure (ETD)

randomised between nominal ETD and ETD + 10 minutes. Details are listed in the fast time simulation

report.

The following is a summary of the flights simulated over 31 days of airport operations:

2,755 flight plans

442 IFR/Light

546 IFR/Medium

11 IFR/Heavy

1,756 VFR/Light

Representing 6435 runway movements

The spreadsheet compiled by Tamworth Tower ATC staff to monitor airport activity during tower hours

indicate, for the period July 2008 to August 2009, an average monthly movement rate of:

892 IFR flights

o 517 Light

o 372 Medium

o 3 Heavy

2,589 VFR flight

3,766 Circuits

This suggests an actual average runway movement rate of between 5,264 and 7,247 per month,

depending on how circuits are counted in relation to VFR flights as runway movements.

6.4 Modelling rationale, assumptions and limitations

The process used for this study has been based on To70‟s experience with airspace risk modelling as a tool

to monitor the appropriateness of various levels of service in particular airspace configurations under

prevailing and forecast air traffic demand.

For this study, an annual movement rate of approximately 90,000 movements was estimated. This

number is based on information supplied by Airservices and all reasonable attempts were made to

validate the data. The validation process entailed requesting inputs by operators and airport managers

(see stakeholders).

12 Times in Aviation are generally expressed in Universal Time Coordinated (UTC). Eastern Standard Time

(EST)is UTC +9hours


6.5 Modelling „intent‟

By modelling the flight paths of flights constrained only by basic AIP procedures and flight planning

requirements and independently of Air Traffic Management (ATM) service levels, it is possible to predict

how flights may come into conflict with one another as conflict pairs, and how conflict pairs present in

terms of frequency and severity.

6.6 Conflict definition

For the purposes of this study, a notional separation standard of 1000ft vertically or 5NM horizontally is

assumed. The fast time simulation system (AirTOp™) will then report any instance when both the vertical

and horizontal standard would be breached if both aircraft in a pair continue on their intended trajectory

without regard to the conflict. Instances in which more than two aircraft are involved in a conflict situation

are reported as multiple conflict pairs.

As well as providing detailed information on the geometry of each conflict, AirTOp™ will categorise the

severity of each conflict in terms of the separation at the closest point of approach of the aircraft to one

another.

Figure 5: Lateral conflict criteria

Conflict severity is classified according to the distance between the simulated flight paths at the closest

point of approach (CPA). The conflict severity classes are shown in table 11.


Conflict Severity Code Minimum Lateral Separation Observed

0 <= 0.5nm

1 > 0.5nm <=1.25nm

2 >1.25nm <=2.5nm

3 >2.55nm <=5nm

4 >5nm <=6nm

5 >6nm <= 7.5nm

6 >7.5nm <=10nm

Table 11 Conflict Severity Classification (source fast time simulation report)

6.7 Simulation volume

As previously mentioned, the flights „of interest‟ to the simulation take place within a 50NM radius of

Tamworth Airport at or below 5000ft. Conflicts that occur within the Tamworth control Are (CTA) Class D,

control zone (CTR) and CTA step are reported on in detail. Figure 6 shows the relevant airspace.

6.8 Flight procedures

As far as is practicable, the flight procedures modelled reflect those that would be followed in the absence

of and ATC tower control service. These have been extracted from AIP Australia, Enroute (ENR) and

Enroute Supplement Australia (ERSA) subsection Noise Abatement Procedures (NAP), and from advice

received during the site visit. A contra circuit pattern is utilised on the parallel runways i.e. left circuits for

runways 30L and 12L and right circuits for runways 30R and 12R.

Figure 6: Tamworth Class "D" airspace (source To70)


Flights returning to the circuit from training flights use an „upwind join‟ procedure which entails flying

overhead the field 1000ft above circuit altitude in the direction of the final approach track. Descent to

circuit altitude is completed upwind and on crosswind legs of the circuit. While it is debatable whether or

not this procedure would be usable without an airport service, it has been modelled since it offers a

practical way to use both parallel runways simultaneously.

Circuit joins for training instrument approaches are generally initiated overhead the field.

Figure 7 shows the airport layout as implemented in the AirTOp™ model.

Figure 7 Tamworth Airport as implemented in AirTOp ™ (source

AirTOp™)


6.9 Limitations

The model has been run assuming visual flight conditions (bad weather days are noted in the tower

statistics list at the rate of less than one per month). This assumption is supported by the contention that

when weather conditions deteriorate, participation by VFR operations is reduced with an arguable

reduction in conflict potential.

6.10 Simulation process

The airport and airspace model was tested progressively, as it was built to ensure the best possible

compliance with normal operating practice. Once the model was complete, the five segments of the flight

schedule (4 x 7 days, 1 x 3 days) were run through the model, once with operations on RWY 12 and once

with operations on RWY 30. During this process, some additional modifications were progressively made

to the model design. The model was rerun as required to ensure that all segments of the flight schedule

were run on a consistent model base. Data on the conflicts pairs detected was collected during the final

set of runs (10 runs in all).

Given that the input data patterns are relatively cyclical over any of the weeks represented in the supplied

and derived data, it was not considered necessary to further randomise aircraft start times.

Thus results are obtained for 31 days of operations using RWY 12, and 31 days using RWY 30. It should be

possible to aggregate these results in proportion to arrive an annual representative data set for entry to

the Airspace Risk Model.

6.11 Observations made

The input data provided and the additional flight plans added in respect of local circuit operations

amount to some 88 flights per day in the Tamworth Class D airspace. Approximately two thirds of these

flights are VFR training flights operated by BAE FTT. In addition, a significant number of these flights

conduct touch and go circuit operations resulting in an estimated average 73 additional runway

movements per day.

During simulated operations in the 12 direction, 14 conflicts were observed involving at least one IFR

aircraft in the 75 minute period after the nominal cessation of the ATC Aerodrome control service. Two of

these conflicts involved a CPA within 2NM and 500ft. For operations in the 30 direction, 11 conflicts

involving at least one IFR aircraft were observed in the 45 minutes after nominal cessation of the ATC

service. Again, two of these conflicts involved a CPA within 2NM and 500ft.

6.11.1 Conflict distribution in detail

The following tables and figures summarise the findings by time of day geographical distribution and

conflict severity, further details can be found in the fast time simulation report. The paragraph provides a

description of the recorded potential conflicts with respect to flight rules and minimum lateral and

vertical separation observed. Conflicts detected outside of the lateral and vertical separation minima as

listed in tables 12 (RWY 12) and 13 (RWY 30) are outside the study airspace and therefore not included.


Separation At least one IFR

aircraft Two VFR aircraft Total

Lateral Vertical

2 NM < 5 NM 500ft < 1000ft 460 8770 9230

1 NM < 2NM < 500ft 101 557 658

0.5 NM < 1NM < 500ft 27 130 157

< 0.5NM < 500ft 6 110 116

Total 594 9567 10161

Table 12 Conflict distribution and separation category for RWY 12 (source To70)

Separation At least one IFR

aircraft Two VFR aircraft Total

Lateral Vertical

2 NM < 5 NM 500ft < 1000ft 672 7942 8614

1 NM < 2NM < 500ft 77 399 476

0.5 NM < 1NM < 500ft 19 169 188

< 0.5NM < 500ft 7 137 144

Total 775 8647 9422

Table 13 Conflict distribution and separation category for RWY 30 (source To70)

Results for RWY 12 and RWY 30 show a similar outcome. The natures of the potential conflicts as well as

the geographical locations are very similar. Therefore the results for RWY 12 are used as a representative

example for further analysis in this study. Further explanation can be found in chapter 6.12.2, details are

listed in the fast time simulation report.


Figures 8 to 11 summarise the findings for RWY 12 and RWY 30 by time of day, further details can be found in the fast time simulation report.

Figure 8: Conflict Distribution by Time of Day – RWY 12 operations VFR only conflicts (source To70)

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Runway 12 Operations VFR Only(31 Days)

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Figure 9: Conflict Distribution by Time of Day – RWY 12 operations conflicts Involving IFR Flights (source To70)

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Runway 12 Operations - IFR Involved(31 Days)

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Figure 10: Conflict distribution by time of day – RWY 30 operations VFR only conflicts (source To70)

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Figure 11: Conflict distribution by time of day – RWY 30 operations conflict involving IFR flights (source To70)

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<2nm/<500ft

<5nm/<1000ft

FINAL DRAFT REPORT


Figures 12 and 13 show the geographic location of the detected potential conflicts with the closest CPA.


AirTOp™/Google)

FINAL DRAFT REPORT



AirTOp™/Google)

All conflicts shown in figures 12 and 13 occurred in the traffic circuit. The conflicts with the CPA from RWY 12 operations

(as the representative results for this study) will be further analysed in chapter 6.12.2 ff.

A detailed tabulation of a broader range of conflict pairs is given in Appendix 5. Further details can be found in the fast

time simulation report.

6.12 Airspace risk assessment

For the purpose of this review, the Airservices data as described in section 6.3 has been used for the study. The input to

the data makes assumptions with regards to charter and circuit movements and the figures represented in this data set

are larger than the BITRE numbers.

FINAL DRAFT REPORT


6.12.1 Estimated traffic mix

Historic flight planned data and an estimate of VFR traffic during the opening hours of the control tower supplied by

Airservices, is used to estimate the traffic mix at Tamworth. The results are summarised in Table 14 below. The ratio of

VFR flights to IFR flights is approximately 3:1.

IFR VFR Total

Arrivals 5,617 16,308 21,925

Departures 5,661 16,308 21,925

Circuits 0 46,508 46,508

Total movements as per count 11,278 79,124 90,402

Table 14 Estimated traffic mix at Tamworth as at June 2009

The airport operator monitors and records the after tower hours movements at the airport. According to the information

available and the BAE FTT training sheets provided, another 10 percent can be added to the total number of movements

provided by Airservices. This will then lead to a total number of aircraft movements in the period between July 2008 and

June 2009 of 99,000.

6.12.2 Potential conflict pairs as found in the fast time simulations

As part of the examination of the conflict pairs, the pairs were grouped according to the constituent aircraft, i. e by flight

rules and aircraft capacity. In addition, the following classifications were applied to the traffic pairs:

VFR - VFR conflicts in RWY 12 operations constitute the majority of all potential conflicts detected involving

94percent of all traffic (versus 92percent for RWY 30 operations).

Of the 594 potential conflicts identified for RWY 12, with at least one IFR aircraft involved, only 33 aircraft came

into proximity of less than 1NM and 500ft. Only 7 aircraft passed within 0.5NM and 500ft one of these occurred

outside the study airspace and can therefore be dismissed.

Table 15: Summary of characteristics for the closest conflicts observed during RWY 12 ops. It lists the characteristics of the

six closest conflicts observed during the simulation of operations in the 12 direction. Results for RWY 30 show a similar

outcome, therefore the results for RWY12 will be used as a representative example for this study. Further details can be

found in the fast time simulation report.

Conflict #13 Conflict Type

Vertical

Separation (FT)

Lateral

Separation (NM)

TW_14#314_IL_TW_14#317_IM_1 SameTrack BothInVertical 29 0.4

TW_20#78_IL_TW_20#97_IM_3 SameTrack BothInVertical 0 0.2

TW_17#547_IL_CTRC4_VL#4_1 Crossing BothInVertical 170 0.1

TW_20#289_IL_CCTN6_VL#1_1 Opposite BothInVertical 210 0

TW_11#8_IM_TW_11#9_IM_3 SameTrack BothInVertical 192 0

TW_3#526_IM_CCTLC4_VL#1_1 Crossing BothInVertical 0 0.3

Table 15: Summary of characteristics for the closest conflicts observed during RWY 12 ops

13Conflicts are extracted from the fast time simulation report

FINAL DRAFT REPORT


The call signs used in this table are created by AirTOp™ to assign a unique identification number to each potential

conflict detected. A detailed list of conflicts can be found in the simulation report.

The conflicts are identified by the Aircraft Identification (ACID) of the aircraft involved separated by a dash and a suffix

showing:

either V indicating VFR flight category or I indicating IFR flight category

and:

o L indicating Low capacity - ≤ 9 seats

o M indicating medium capacity 9 or more seats but less than and 38 seats

o H indicating more than 38 seats

Tables 16 and 17 show the distribution of the conflicts observed where the CPA was less than 500ft and 0.5NM, classified

according to flight category and aircraft capacity in the two operating modes studied in the simulation.

RWY 12 Operations VL IL IM

VL 133

IL 2 0

IM 1 2 1

IH 0 0 0

Table 16: Distribution of conflicts (CPA <500ft and 0.5NM) by flight category and capacity – RWY 12 operations

(source To70)

RWY 30 Operations VL IL IM

VL 137

IL 3 0

IM 4 0 0

IH 0 0 0

Table 17: Distribution of conflicts (CPA <500ft and 0.5NM) by flight category and capacity –RWY 30 operations

(source To70)

The conflicts as listed in table 15 were analysed in terms of severity, number of occurrences and location of closest

proximity.

All flights are either local IFR training flights interacting with an IFR arrival or departure, or with an aircraft doing VFR

circuits. The incidents occurred either on final or in the traffic circuit and are clearly within Tamworth Class D airspace.

One potential conflict occurred outside of the simulation area and is not listed in the table listing the most severe

potential conflicts as found in the simulation. It will be addressed separately in chapter 6.12.6.1.

FINAL DRAFT REPORT


6.12.3 Compare airspace design and defence mechanisms with conflicts

The simulation study to identify conflict pairs only reported on those conflicts observed within the airspace controlled by

Tamworth ATC. However, in order to do this effectively, it was considered prudent to observe all traffic within 50NM of

the airport. Over the 31 days of operations simulated with operations in the 30 direction, no serious conflicts were

observed outside the Tamworth airspace within 50NM. During the 31 days of simulation with operations in the 30

direction, one significant conflict between two IFR aircraft was observed outside the Tamworth airspace but within 50NM

of the airport. This conflict occurred in airspace under the control of ATC at Brisbane ATSC.

ATC services as defined by Class D airspace apply. The main features are:

IFR separated from IFR and Special VFR. Traffic information provided on all VFR;

Speed limited to 250kts indicated air speed (IAS) below 10000ft AMSL;

Continuous two-way radio required;

Clearance required from ATC to enter airspace.

Defences in place:

Aircraft involved in the potential conflicts as listed above would have been on ATC frequency and received a clearance to

enter the airspace. Traffic information would have been provided and the aircraft sequenced into the traffic circuit by

ATC.

In Class D airspace, IFR aircraft are separated from other IFR aircraft. Three out of the six closest potential conflicts found

involved two IFR aircraft. ATC would apply separation standards as described in the Airservices Manual of Air Traffic

Services (MATS). In the other three cases, all aircraft would have been on ATC frequency and would have received either

instructions (IFR) or traffic information (IFR and VFR) about other aircraft.

Two way communications would have ensured that pilots and ATC maintained situational awareness. ASIR and ESIR

reports about VCA provided no indication that aircraft entered the traffic circuit without clearance. As already discussed

in chapter 5 violation of controlled airspace mainly happened due to human error e.g. when aircraft did not receive a

clearance to enter controlled airspace in time or a pilot misinterpreted an ATC instruction. No other reports about

airspace related incidents could be found.

The potential risk of a conflict between the aircraft involved is, as a result, very low.

6.12.4 VFR traffic

The AirTOp™ simulation tool has the capability to accurately model circuit operations as part of airport movements. The

output from the fast time simulation system facilitates the identification of aircraft pairs between which their closest

proximity falls below an arbitrary level. This applies to IFR aircraft as well as VFR aircraft.

There are no defined standards regarding separation minima between VFR aircraft. In this study proximity between pairs

of VFR aircraft are reported against the same criteria used for IFR aircraft. During the simulation 133 VFR aircraft pairs had

a CPA of less than 0.5NM and 500ft during RWY12 operations. The results for RWY 30 operations showed a similar number

(137 potential conflicts). Most of these potential conflicts occurred in the traffic circuit area.

FINAL DRAFT REPORT


The following graphic figure 14 shows the location of potential conflicts (closest in red, all others in yellow) for RWY 12

operations.

Figure 14: Location of potential conflicts for RWY 12

Defences in place:

A proximity of less than 0.5NM and 500ft may not be considered unusual between two VFR flights operating in a traffic

circuit environment. In order to maintain safe operations in these conditions pilots must maintain high levels of

situational awareness based on timely visual acquisition of conflicting aircraft.

VFR aircraft in the Tamworth traffic circuit are operating in Class D airspace during tower hours. As described in Chapter

6.12.3 the main features of this airspace are:

IFR separated from IFR and Special VFR. Traffic information provided on all VFR.

VFR receives traffic on all other aircraft but not separated by ATC.

Special VFR separated from Special VFR when visibility is less than Visual Meteorological Conditions (VMC).

Speed limited to 250kts IAS below 10000ft AMSL

Continuous two-way radio required

Clearance required from ATC to enter airspace.

VFR aircraft entering Class D airspace require a clearance from ATC. This will enable ATC to provide traffic information to

the aircraft operating in the airspace. The fact that radio use is mandatory enables all aircraft to gain additional situational

awareness regarding others in the same airspace. This situational awareness is facilitated by clearances and instructions

such as sequence number in the circuit and information about preceding and succeeding traffic.

FINAL DRAFT REPORT


In addition, BAE FTT has set up a runway caravan to assist the circuit training, providing student pilots with additional

situational awareness. BAE FTT pilots are receiving advice about aircraft configuration (e.g. gear down and in place),

traffic in the vicinity and the type of landing to be commenced (touch and go, full stop landing, low approach etc.). This

service is provided for all BAE FTT circuit activities even when the control tower is closed and appears to be similar to a

UNICOM service provided at Class G airspace locations.

In summary the defences in place including the requirement to obtain a clearance to operate in Class D airspace and the

additional situational awareness facilitated by mandatory two way radio communication provide a high level of

assurance of timely visual acquisition between conflicting aircraft in the vicinity of the airport. This supports a conclusion

that all reasonable measure are in place to mitigate the collision risk for VFR aircraft operating in Tamworth Class D

airspace.

6.12.5 Airservices‟ “Preliminary Risk Assessment of 10 Class D Towers”

In 2008, Airservices conducted risk assessments of 10 Class D Towers using a qualitative and quantitative risk assessment

approach supported by fast time simulation and the use of an airspace risk model. The fast time simulation model used

excluded the airspace below 1500ft and traffic circuits due to a model limitation of the simulation software used.

The results indicated that within the constraint mentioned above, the airspace around Tamworth constitutes the lowest

risk of all 10 Class D Tower locations in the country. The risk was assessed to be 0.008 fatalities per 100 years.

General issues about dimensions of Class D airspace, pilot education about CTAF procedures, and standardisation of

procedures across the country were discussed.

The study also revealed that there were no significant issues related to airspace design and classifications identified.

6.12.6 Airspace surrounding Class D – Class C and Class E

As previously described in chapter 3, Tamworth ATC , controls the Class D airspace 4500ft AMSL and below and Class C

airspace above 4500ft AMSL up to 8500 ft AMSL during the opening hours of the control tower. Brisbane ATSC controls

the airspace above 8500ft AMSL. The airspace is „keyhole‟ shaped to the southeast of the field capturing the extended

runway centrelines of RWY12/30. The control area steps are predominately to the southwest of the field to capture

tracking of RPT aircraft.

The methodology used for this aeronautical study does not provide the capability to distinguish between different

classes of services provided on a sufficient quantitative basis, but will lead this argument on the basis of the findings as

discussed earlier in chapter 612.1 to 6.12.4.

6.12.7 Airservices‟ “Risk Assessment Class E over Class D airspace”

As part a process of reforming airspace, Airservices conducted a comprehensive review of the airspace changes referred

to as Stage 2b of the National Airspace System (NAS), which were implemented on 27 November 2003.

The report was published on the Airservices website, and compares the risks of operating in Classes C and E above Class

D control zones from 4500ft.

FINAL DRAFT REPORT


The analysis documented in the report was completed using a two stage modelling technique:

A fast time simulation to estimate the frequency and nature of potential aircraft conflict pairs over a one year period

in the airspace.

Fault Tree (Airspace Risk Model) as a structured method of examining the probability that a conflict pair will result in

a collision.

The study showed the following key results for Tamworth (table 18):

Accidents per 100 years Fatalities per 100 years

Class E 0.175 1.13

Class C 0.007 0.05

percent reduction (Class C vs. Class E) 96percent 96percent

Table 18: Tamworth study results (source Airservices)

Key conclusions of the study were:

In general terms, Class E airspace presents the highest overall collision, fatality and individual risk of the three

options;

Those locations with a higher proportion of VFR movements presented the highest risk levels overall, and a greater

relative difference between Class E and Class C. The level of VFR traffic has a very strong influence on the risk

estimates;

The collision risk in all locations was sensitive to the speed restrictions that Class E airspace imposes on aircraft

below 10,000 feet. The speed restriction of 250kts below 10000 feet in Classes E and D has a noticeable effect on the

likelihood of visual acquisition.

The Airservices study also showed that, should Class E service be provided instead of the current Class C service, the

risk would increase and exceed the risk according to the DNV limits.

Recent airspace reform initiatives such as the mandatory requirement to carry a functional transponder in Class E

airspace raise the question whether a new study should be initiated in order to re-assess the risk associated with Class E

over Class D airspace taking into account all changes in regulations and traffic data occurred since the Airservices study

was completed.

It can be assumed that the mandatory requirement to operate transponder in Class E airspace will contribute to reduce

the risk of operating in this airspace, but the extent of this change needs to be further evaluated.

6.12.8 Class C airspace above Tamworth Class D airspace

The findings of this study show that one of the most severe types of potential conflicts (less than 0.5NM and 500ft

separation) occurred outside the traffic circuit and Tamworth Class D airspace. The potential conflict occurred in Class C

airspace above Tamworth CTR and involved at least one IFR flight. Most IFR flights involve passenger transport or cargo

flights with medium to high capacity aircraft.

FINAL DRAFT REPORT


ATC services as defined by Class C airspace apply. The main features are:

IFR separated from IFR, VFR and Special VFR (SVFR) by ATC, no speed limitation for IFR operations,

Continuous two-way radio required. Clearance required from ATC to enter airspace.

VFR receives traffic information on other VFR but not separated from each other by ATC. Speed limited to 250 kts IAS

below 10,000ft AMSL, continuous two-way radio required. Clearance required from ATC to enter airspace.

Special VFR separated from Special VFR when visibility (VIS) is less than VMC. Speed limited to 250kts IAS below

10,000ft AMSL*, continuous two-way radio required. Clearance required from ATC to enter airspace.

Transponder required within surveillance coverage

The services provided in Class C airspace ensure that IFR flights are always separated from all other flights; therefore one

can lead the argument that Class C airspace provides better protection for IFR flights than Class E where only IFR to IFR

flights are separated. VFR flights in Class C airspace are receiving traffic information on other VFR aircraft while VFR flights

in Class E airspace are receiving traffic information on other VFR flights only if practicable. This means the ability to

provide traffic information to VFR aircraft depends on work load and traffic situation and is not guaranteed at all times.

It is hence clear that the services provided in Class C airspace when there are VFR aircraft „in the mix‟ is always safer for IFR

flights compared to Class E airspace. In addition, the Airservices study as described in chapter 6.12.7 showed that Class E

would increase the risk in the airspace to an intolerable level.

In certain cases, it will not always be necessary to provide a higher class of service at certain locations because of local

factors such as low traffic figures or the low frequency of RPT flights. The conduct of an airspace risk analysis together

with a cost benefit analysis will provide the necessary basis for the airspace regulators decision about the correct service.

Principles such as safety and equitable access to the airspace should be considered at all times. Due to the relatively high

traffic volume at Tamworth, it could be concluded that the requirement to obtain a clearance to enter Class C airspace

will sometimes cause delay for VFR aircraft trying to enter controlled airspace. Airservices is providing two separate

working positions and frequencies for the aerodrome controller in order to separate radio traffic for the two main

runways. All traffic on the smaller runway, mainly used for VFR traffic circuits and BAE FTT training flights departing and

arriving, is handled on a separate controller work station and frequency. This measure is designed to minimise frequency

congestion and delay for aircraft entering controlled airspace. In all documentations provided, there was not enough

evidence to support the argument to change to Class E.

Most risk management systems are premised on the concept of As Low As Reasonably Practicable (ALARP).

In doing so, there is an acceptance that not all risk can or should be eliminated. There are practicable limits to which the

aviation industry is able to go and the extent to which the industry and the community will pay to reduce adverse risks.

In this context, it is interesting to note the words of Chief Justice Sir Harry Gibbs of the High Court of Australia (1982):

“Where it is possible to guard against a foreseeable risk, which, though perhaps not great, nevertheless cannot be called

remote or fanciful, by adopting a means, which involves little difficulty or expense, the failure to adopt such means will in

general be negligent.”

In summary it can be said that this aeronautical study did not identify significant issues with the Class C service provided

above Tamworth Class D airspace. The potential benefit of easier access to the airspace above Class D for VFR flights that

may result from a re classification of that airspace to E is not evident and is strongly opposed by RPT operators on safety

grounds.

Further risk analysis and a thorough cost benefit analysis would be required to properly investigate the potential for

changing the classification of the airspace above the Tamworth Class D airspace.

FINAL DRAFT REPORT


7 Findings

Both simulation and consultation with the airspace users indicate that the current airspace classification allows for the

safe conduct of all operations including regular public transport (RPT).

The study revealed:

The results of the fast time simulation of the airspace around Tamworth lead to the conclusion that the Class D

airspace with the relevant procedures applied will provide sufficient defences against the most severe potential

conflicts identified;

The dimensions of Class D and Class C airspace around and above Tamworth are deemed to be adequate by the

airspace users and air traffic control. The results of the fast time simulation did not provide any other evidence to the

contrary and no documentation was found during the study stating the opposite;

All airspace users consulted indicated that the airspace classification utilised is suitable for its current use;

Approximately 10 percent of all movements at Tamworth are conducted outside of the tower hours and are

therefore operating under CTAF(R) procedures. The main contributor is BAE FTT with night circuit training on the

main runway;

During the week, when BAE FTT night flight training takes place, there is one RPT night flight operating after the

closure of the control tower. BAE FTT will try to avoid night circuit training until the RPT aircraft has landed whenever

possible in order to minimise any interference with RPT operations;

Although the fast time simulation found some potential conflicts for this time of the day, the interviews with BAE

FTT, Airservices and the airport operator as well as the analysis of air safety incident report (ASIR) and electronic

safety incident report (ESIR) data showed no incidents between RPT and training aircraft performing night circuits;

BAE FTT has set up a runway caravan to assist the circuit training with providing additional situational awareness to

the pilots in the traffic circuit. This could be seen as an additional risk mitigator;

ASIR and ESIR data indicate that failure to observe Air Traffic Control (ATC) instructions and violation of controlled

airspace (VCA) are the most observed airspace related concerns reported. These incidents are mainly related to

human error such as misinterpreting ATC instructions and cannot directly be linked with the design and class of

airspace provided at Tamworth;

Less than one in two hundred flights in the period from July 2008 to June 2009 relate to reported ESIR incidents such

as failure to comply with instructions or procedures (violation of controlled airspace, failure to comply ATC

instructions or procedures and runway incursion). Most of the incidents were related to (student) pilot errors or

misinterpretation of ATC instructions. An analysis of the ASIR reports of the last 5 years showed the same result.

This leads to the conclusion that the airspace design and classification of Tamworth can be considered to be appropriate

for its use.

Based on this study, To70 recommends that:

CASA should review the ESIR and ASIR incidents categorised as failure to comply with instructions or procedures

(violation of controlled airspace, failure to comply ATC instructions or procedures and runway incursion). About 40

percent of all reported incidents for Tamworth can be related to human error such as violation of controlled airspace

and breakdown of separation/coordination, mainly related to pilot error or misinterpretation of ATC instructions. It is

recommended That CASA should review these incidents and develop training material to minimise these incidents;

CASA should continue monitoring the airspace around Tamworth with particular focus on changes in types and

numbers of movements outside the tower hours and changes in Instrument Flight Rule (IFR) and Visual Flight Rule

(VFR) numbers and training activities;

FINAL DRAFT REPORT


CASA should conduct pilot education to familiarise every airspace user with CTAF(R) procedures14 taking into

account the proposed changes to CAR 166 and potential training and education issues resulting from the changes

Class C airspace above Tamworth Class D airspace should be maintained unless a new aeronautical study using an

airspace risk analysis methodology and cost benefit analysis can prove significant benefits for Class E airspace.

It is recommended that the OAR maintain a watch of activity at Tamworth aerodrome during the bi-annual review of

movement data, and, if total aircraft movements significantly increase, or after five years, whichever occurs first,

further airspace review or an aeronautical study will be conducted to reassess the risk to RPT operations.

FINAL DRAFT REPORT


Appendix 1 – Acronyms

AAPS 2007 Australian Airspace Policy Statement, 28 June 2007

ACD Airways Clearance Delivery

Act Australian Airspace Act 2007

ADC Aerodrome Control

AENA Aeropuertos Españoles y Navegación Aérea

AFRU Aerodrome Frequency Response Unit

AGL Above Ground Level (in feet)

AI Aerodrome Inspector

AIP Aeronautical Information Publication

Airservices Airservices Australia

ALARP As Low As Reasonable Practical

AMSL Above Main Sea Level

ANSP Air Navigation Service Provider

ARA Airservices Aerodrome Research Application

ARM Airspace Risk Model

ASIR Aviation Safety Incident Report

ATIS Automatic Terminal Information Service

ATC Air Traffic Control

ATM Air Traffic Management

ATS Air Traffic Services

ATSB Australian Transport Safety Bureau

ATSC Air Traffic Services Centre

BAE FTT British Aerospace Flight Training Tamworth

BITRE Bureau of Infrastructure, Transport and Regional Economics (Department)

BOM Bureau of Meteorology

CASA Civil Aviation Safety Authority

CASR Civil Aviation Safety Regulations 1998

CPA Closest Point of Approach

CTA Controlled airspace

CTAF Common Traffic Advisory Frequency

CTAF(R) Common Traffic Advisory Frequency (Radio Required)

CTR Control Zone

DAH Designated Airspace Handbook (AIP)

DAP Departure and Approach Procedures (AIP)

DHC-8 Bombardier Dash 8

DME Distance Measuring Equipment (Navigational Aid)

DLR Deutsche Forschungsanstalt für Luft- und Raumfahrt

DNV Det Norske Veritas

DOTARS Department of Transport and Regional Services

ERSA Enroute Supplement Australia

ESIR Electronic Safety Incident Report

EST Eastern Standard Time

ETA Estimated Time of Arrival

ETD Estimated Time of Departure

FINAL DRAFT REPORT


FIS Flight Information Service

ft feet

GNSS Global Navigation Satellite Systems

GPS Global Positioning System

IAS Indicated Air Speed

ICAO International Civil Aviation Organization

IFR Instrument Flight Rules

ILS instrument landing system

IMC Instrument Meteorological Conditions

Kg kilogram

km kilometre

kts knots

LKSC Lake Keepit Soaring Club

LOC Localizer

m Metres

NAP Noise Abatement Procedures

NDB Non-Directional Beacon (Navigational Aid)

NLR Nationaal Lucht- en Ruimtevaartlaboratorium

NM Nautical Miles

OAR Office of Airspace Regulation (CASA)

ODW Operational Data Warehouse

PAL Pilot activated lighting

pax passenger

RAAF Royal Australian Air Force

RNAV Area Navigation

RPT Regular Public Transport

RWY Runway

SAR Search and Rescue

SMC Surface Movement Control

SVFR Special VFR

TAAM Total Airspace and Airport Modeller

TOD Top of descent

TWR Control Tower

UTC Universal Time Coordinated

VCA Violation of Controlled Airspace

VFR Visual Flight Rules

VHF Very High Frequency (radio)

VIS Visibility

VMC Visual Meteorological Conditions

VOR Very High Frequency (VHF) Omni-Directional Radio Range (NavAid)

FINAL DRAFT REPORT


Appendix 2 – Australian airspace structure Class Description Summary of Services/Procedures/Rules

A All airspace above Flight Level (FL) 180 (east coast) or FL 245

Instrument Flight Rules (IFR) only. All aircraft require a clearance from Air Traffic Control (ATC) and are separated by ATC. Continuous two-way radio and transponder required. No speed limitation.

B Not currently used in Australia

C

In control zones (CTRs) of defined dimensions and control area steps generally associated with controlled aerodromes

All aircraft require a clearance from ATC to enter airspace. All aircraft require continuous two-way radio and transponder. IFR separated from IFR, Visual Flight Rules (VFR) and Special VFR (SVFR) by ATC with no speed limitation for IFR operations. VFR receives traffic information on other VFR but are not separated from each other by ATC. SVFR are separated from SVFR

when visibility (VIS) is less than Visual Meteorological Conditions (VMC). VFR and SVFR speed limited to 250 knots (kt) Indicated Air Speed (IAS) below 10,000 feet (ft) Above Mean Sea Level

(AMSL)*.

D Regional locations such as Hobart and Alice Springs

All aircraft require a clearance from ATC to enter airspace. As in Class C airspace all aircraft are separated on takeoff and landing. All aircraft require continuous two-way radio and are speed limited to 250 kt IAS below 10,000 ft AMSL*.

IFR are separated from IFR, SVFR, and are provided with traffic information on all VFR. VFR receives traffic on all other aircraft but are not separated by ATC. SVFR are separated from SVFR when VIS is less than VMC.

General Aviation

Aerodrome Procedures

(GAAP)

High density General Aviation aerodromes

All aircraft require a clearance from ATC to enter airspace. All aircraft require continuous two-way radio and are speed limited to 250 kt IAS.

In VMC all operations are VFR, traffic information only provided. In Instrument Meteorological Conditions (IMC), IFR are separated from all traffic. SVFR are separated from SVFR when VIS is less than VMC.

E Controlled airspace not covered in classifications above

All aircraft require continuous two-way radio and transponder. All aircraft are speed limited to 250 kt IAS below 10,000 ft AMSL*,

IFR require a clearance from ATC to enter airspace and are separated from IFR by ATC, and provided with traffic information as far as practicable on VFR.

VFR do not require a clearance from ATC to enter airspace and are provided with a Flight Information Service (FIS). On request and ATC workload permitting, a Radar / ADS-B Information Service (RIS) is available within surveillance coverage.

F Not currently used in Australia

G Non-controlled

Clearance from ATC to enter airspace not required. All aircraft are speed limited to 250 kt IAS below 10,000 ft AMSL*. IFR require continuous two-way radio and receive a FIS, including traffic information on other IFR. VFR receive a FIS. On request and ATC workload permitting, a RIS is available within surveillance coverage. VHF radio

required above 5,000 ft AMSL and at aerodromes where carriage and use of radio is required.

* Not applicable to military aircraft

FINAL DRAFT REPORT


Appendix 3 –Aerodrome Research Application (ARA) data for Tamworth

FINAL DRAFT REPORT


FINAL DRAFT REPORT


Appendix 4 – AirTOpTM

AirTOp™ is the latest generation fast time gate-to-gate simulation tool developed by AirTopsoft and the German Air

Navigation Service Provider DFS. To70 is the first non ANSP to acquire the tool. This has allowed To70 to co-develop the

tool, resulting in a cost efficient and flexible tool for analysing the future challenges that ANSPs and airport operators

face. AirTOp‟s interface and data structure has been modified to seamlessly interact with To70‟s in-house developed

tools, such as the radar-track tool, EarthGate and the Integrated Noise Model. AirTOp™ is used by the major European

ANSPs and research organisations DFS, Skyguide, UK NATS, AENA, NLR, DLR and Eurocontrol.

AirTOp™ provides the following advantages over other fast time simulation software such as the Total Airspace and

Airport Modeller TAAM™:

The ability to accurately model “line up and hold” and circuit operations giving a much improved representation

and assessment of runway throughput/capacity;

Future( near term) enhancements will include the ability to model ground vehicle movements;

The operating costs of AirTOp™ will be much lower than the cost of TAAM™.

AirTOp™ provides the ability to quickly adapt the model to reflect the unique operations at individual airports

Some of the AirTOp™ functionalities are:

Multi-agent based to better capture controller roles, tasks and workload;

Integrated table and map based scenario editing capabilities. External format import support;

Open, modular and extensible using the AirTOp Development suite. Reduces operational costs and enhancement

delays

Includes user settable rule based system to define en-route restrictions, re-routing, approach and departure

sequencing, runway dependencies etc.;

Simulates radar controllers (departure, en route, pickup, feeder), planning controllers and airport controllers (startup,

tower, etc.) task.


Appendix 5 – Summary of Conflicts Observed Summary of characteristics for the most severe conflicts observed during RWY 12 ops.

CONFLICT Conflict Type

Vertical Separation

(ft)

Lateral Separation

NM Altitude

(AGL)

TW_14#314_IL_TW_14#317_IM_1 SameTrack BothInVertical 29 0.4 4526ft

TW_20#78_IL_TW_20#97_IM_3 SameTrack BothInVertical 0 0.2 1000ft

TW_17#547_IL_CTRC4_VL#4_1 Crossing BothInVertical 170 0.1 1085ft

TW_20#289_IL_CCTN6_VL#1_1 Opposite BothInVertical 210 0 1895ft

TW_11#8_IM_TW_11#9_IM_3 SameTrack BothInVertical 192 0 1096ft

TW_3#526_IM_CCTLC4_VL#1_1 Crossing BothInVertical 0 0.3 1000ft

CCTL5_VL#3_FORM5_2 SameTrack BothInVertical 0 0.4 1000ft

TRA_VL#36_CCTS_VL#3_2 SameTrack BothInVertical 0 0.4 2000ft

MOR-TW_VL_TRA_VL#34_2 SameTrack BothInVertical 0 0.1 1000ft

TRA_VL#33_CCTS_VL#2_1 SameTrack BothInVertical 65 0 1049ft

TRA_VL#23_TRCC_VL#3_1 SameTrack BothInVertical 57 0.3 1036ft

TRA4_VL#21_CTRC4_VL#8_1 SameTrack BothInVertical 11 0.3 1429ft

CCTS4_VL#4_DU-TW4_VL_2 SameTrack BothInVertical 300 0.2 2150ft

CCTS5_VL#1_TRC5_VL#2_1 SameTrack BothInVertical 41 0.1 1023ft

TRC4_VL#2_CTRC4_VL#5_1 SameTrack BothInVertical 29 0 3303ft

CCTS5_VL#1_TRC5_VL#2_2 SameTrack BothInVertical 419 0 1209ft

TRC5_VL#4_TW-MOR5_VL_1 Opposite BothInVertical 235 0.3 3117ft

CCTL5_VL#3_TRC5_VL#3_2 Crossing BothInVertical 0 0.1 3000ft

TRC6_VL#14_CCTS6_VL#12_3 SameTrack BothInVertical 28 0.4 1014ft

CCTS6_VL#6_S-APP6_VL_1 Crossing BothInVertical 273 0.4 1144ft

TRA7_VL_CCTS7_VL_1 SameTrack BothInVertical 331 0.4 1992ft

TRC6_VL#19_CCTL6_VL#7_3 SameTrack BothInVertical 436 0.4 2218ft

TRA6_VL#12_CCTS6_VL#17_1 Crossing BothInVertical 0 0.3 3000ft

CCTL6_VL#5_CCTL6_VL#6_12 SameTrack BothInVertical 79 0.3 1039ft


TRA6_VL#1_CCTS6_VL#6_3 SameTrack BothInVertical 0 0.2 1000ft


TRC6_VL#19_CCTS6_VL#16_1 Crossing BothInVertical 80 0.2 3960ft






TRA6_VL#8_CCTL6_VL_3 SameTrack BothInVertical 490 0.1 1245ft

TRA6_VL#6_TRC6_VL#11_1 Crossing BothCruising 0 0 3000ft

TRA6_VL#9_CCTL6_VL#3_1 Crossing BothInVertical 0 0 3000ft



TRA7_VL#38_CCTL7_VL#3_3 SameTrack BothInVertical 65 0 1032ft




Vertical Separation

(ft)

Lateral Separation

NM Altitude

(AGL)



WLM-TW_VL_CCTS_VL#13_3 SameTrack BothInVertical 14 0 1007ft

TRA_VL#9_TRC_VL#7_3 SameTrack BothInVertical 26 0 2049ft

TRC4_VL#7_CCTS4_VL_2 SameTrack BothInVertical 0 0.4 1000ft

TRC4_VL#7_CCTS4_VL_1 Crossing BothInVertical 471 0.4 1776ft


CCTL5_VL#2_TRC5_VL#1_2 SameTrack BothInVertical 354 0.2 1177ft

CCTS4_VL#4_DU-TW4_VL_2 SameTrack BothInVertical 283 0.1 2141ft

CCTS5_VL#2_TRC5_VL#3_1 Crossing BothInVertical 0 0.4 3000ft


CCTL5_VL#3_TRA5_VL#3_2 SameTrack BothInVertical 0 0.2 1000ft


TRC6_VL#15_CCTL6_VL#7_1 Crossing BothInVertical 0 0.4 3000ft

CCTS6_VL#8_S-APP6_VL_1 Crossing BothInVertical 273 0.4 1157ft





TRA6_VL#15_TRC6_VL#20_1 Crossing BothCruising 17 0.2 2991ft

TRA6_VL#7_CCTL6_VL#1_2 SameTrack BothInVertical 273 0.2 1863ft


TRA6_VL#10_CCTL6_VL#6_1 Crossing BothInVertical 0 0.1 3000ft

TRC6_VL#14_CCTL6_VL#7_3 SameTrack BothInVertical 291 0.1 1274ft



TRC6_VL#14_CCTL6_VL#7_2 SameTrack BothInVertical 266 0 2133ft

TRC6_VL#16_CCTS6_VL#17_2 SameTrack BothInVertical 368 0 1184ft







TRA_VL#23_TRCC_VL#3_1 SameTrack BothInVertical 14 0.4 1028ft


TRA_VL#22_CCTS_VL#11_1 Opposite BothInVertical 0 0.1 1000ft



CCTL5_VL_TRA5_VL_2 Crossing BothInVertical 0 0.3 3000ft

TRC4_VL#6_CCTS4_VL_2 SameTrack BothInVertical 218 0.3 1109ft




Vertical Separation

(ft)

Lateral Separation

NM Altitude

(AGL)


TRC4_VL#2_CTRC4_VL#5_1 SameTrack BothInVertical 7 0 2485ft

TRA4_VL#14_CCTS4_VL#3_1 SameTrack BothInVertical 72 0 1036ft

TRA4_VL#16_CTRC4_VL#6_1 SameTrack BothInVertical 117 0 3963ft







TRA6_VL#4_TRC6_VL#9_4 SameTrack BothInVertical 0 0.3 1000ft



TRC6_VL#7_S-APP6_VL_1 Crossing BothInVertical 31 0.3 2984ft





TRC6_VL#10_S-APP6_VL_1 SameTrack BothInVertical 221 0.2 1131ft



TRC7_VL#1_CCTS7_VL_1 Crossing BothInVertical 0 0.1 3000ft


TRC6_VL#19_CCTS6_VL#17_1 Crossing BothInVertical 0 0 3000ft

TRA6_VL#7_CCTL6_VL#3_1 Crossing BothInVertical 40 0 3020ft

TRC6_VL#14_CCTL6_VL#5_4 SameTrack BothInVertical 220 0 2110ft





TRA7_VL#16_CCTS7_VL#5_1 Crossing BothInVertical 0 0 3000ft

TRA7_VL#8_CCTS7_VL#2_2 SameTrack BothInVertical 17 0 1855ft

MOR-TW_VL_TRA_VL#34_2 SameTrack BothInVertical 0 0.2 1000ft


CCTS_VL_TRA_VL#39_1 SameTrack BothInVertical 196 0.3 1098ft




TRA4_VL#17_DU-TW4_VL#1_3 SameTrack BothInVertical 354 0.2 1177ft

CCTL5_VL_TRC5_VL_2 SameTrack BothInVertical 41 0 1020ft

CCTS5_VL_TRC5_VL#1_1 Crossing BothInVertical 187 0 2906ft




Vertical Separation

(ft)

Lateral Separation

NM Altitude

(AGL)



TRC6_VL#7_S-APP6_VL_1 Opposite BothInVertical 31 0.4 2984ft





TRC6_VL#11_CCTL6_VL#1_1 Crossing BothInVertical 110 0.1 3945ft

TRC6_VL#10_S-APP6_VL_1 SameTrack BothInVertical 273 0.1 1209ft


TRC6_VL#15_CCTS6_VL#15_2 SameTrack BothInVertical 436 0 1219ft



TRA_VL#21_TRC_VL#11_3 SameTrack BothInVertical 0 0.1 1000ft

TRA_VL#21_TRC_VL#11_1 Crossing BothCruising 0 0 4000ft


Appendix 6 – Regular Public Transport Questions

Summary of stakeholder responses

The following paragraphs list the answers given by the stakeholders/airspace users in the questionnaire and during the

interviews. General observations made during the site visits and a summary of relevant issues are described in Paragraph 4

of this study.

Operation during peak time:

BAE FTT will have up to three aircraft in the traffic circuit;

Training aircraft will avoid RPT operations wherever possible;

Telephone communication between BAE FTT, Airservices and RPT operator will take place to coordinate any non

standard activities.

Airspace design and service issues:

There are no relevant issues.

Straight in approaches:

RPT operators are using straight in approaches on a regular basis;

Training aircraft do not perform straight in approaches on a regular basis.

Interaction with military traffic:

No interaction for RPT operators;

F18 and C130 aircraft are using the main runway occasionally for low approaches or touch and go. This is usually

coordinated in advance to minimise interference with training traffic.

Interaction with recreational aviation:

The Tamworth Area Radio Model Aircraft Club recently moved to a new location near Somerset and now

operates outside of controlled airspace;

Parachuting does not take place at Tamworth;

Lake Keepit Soaring Club is located approximately 20NM northwest of the Tamworth Airport. Interviews with

stakeholders at Tamworth indicated that the club has established lines of communications with all relevant

parties at Tamworth Airport (e.g. ATC, RPT operators, BAE FTT and airport operator). All competitions are

coordinated with these parties and rules and regulations are enforced to avoid controlled airspace. As a general

rule, all gliders stay outside of controlled airspace.

Air Traffic Control:

All airspace users are happy with the service provided;

The combination of ADF1 and SMC frequencies cause sometimes frequency congestion.

Safety Systems:

BAE FTT, Airservices, all RPT operators and the airport operator have safety management systems in place.

Aero Club / General Aviation:

The Aero Club currently does not own any aircraft;

General aviation activities other than training flights are very low;

A separate training area has been established for General Aviation Training. This will keep the GA aircraft away

from BAE FTT training.

Aircraft transponder:

All operators interviewed stated that there are no known issues relevant to transponder use and equipage.

Flight training:


Lines of communication are established between all major airport users (airport operator, BAE FTT, Airservices) in

order to coordinate and monitor activities. Whenever there is an issue outside of normal operations the relevant

parties will discuss and solve the issue;

There are also local agreements in place (e.g. letter of agreement between BAE FTT and Airservices) to describe

procedures with ATC and RPT airlines;

Effective traffic management measures have been implemented to provide appropriate priority rules for IFR

traffic amongst the density of VFR training aircraft. BAE FTT has set up a runway caravan along the side of the

runway to provide additional situational awareness for the student pilots when commencing traffic circuits. This

also applies for night circuits when the control tower is closed;

Most of the training aircraft are using the smaller runway, 12R/30L, for their operations. The main runway,

12L/30R, is only used by BAE FTT for flight screening15 and IFR training flights. BAE FTT also uses RWY 12L/30R for

night circuit training as it is the only runway equipped with a lighting system.

15 Flight Screening Program is a flying-based assessment of potential candidates conducted at the BAE Systems Training Academy at Tamworth

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