Gulfstream Proprietary Information

Gulfstream Aerospace Corporation

UC Davis Aviation Noise & Air Quality Symposium

“Revolution in Aviation”

March 1, 2009 / Palm Springs, CA

Photo: NASA Dryden Flight Research Center

An Overview of the GulfstreamAn Overview of the Gulfstream

Supersonic TechnologySupersonic TechnologyProgramProgram

Gulfstream Proprietary Information

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Initial Cruise Weight - lb

Initi

al S

hock

Stre

ngth

- ps

f Concorde

HSCT

SBJ

QSJ Shaped

QSJ Advanced Concepts

Initial Cruise Sonic Boom Strength

DARPA QSP Goal

• Advantages– Smaller Aircraft Reduced Sonic Boom– Lower Speed Less Complexity (Inlets, Materials, Etc.)

Civil Supersonics / Concorde is Gone – What Now?Civil Supersonics / Concorde is Gone – What Now?

• Gulfstream Perspective…Quiet Supersonic Jet (QSJ)

– Different Market• Business Jet: Speed is

Important & Affordable

– Different Requirements• High Speed Civil Transport: Mach 2.4, 600K airliner• Quiet Supersonic Jet: Mach 1.8, 100K transport

Better Chance at Enabling Acceptable Supersonic Civil AircraftBetter Chance at Enabling Acceptable Supersonic Civil Aircraft

Gulfstream Proprietary Information

Redefining the Speed EnvelopeRedefining the Speed Envelope

Quiet Supersonic Jet (QSJ)

Today’s Reality Tomorrow’s Vision

Manage Environmental Impacts Through Design RequirementsManage Environmental Impacts Through Design Requirements

Cruise Speed 0.85 M0.85 M 1.80 M1.80 M

Environmental Considerations Requirement• Boom Overpressure Acceptable for Overland SS Flight• Takeoff Emissions ICAO with Margin• Cruise Emissions Minimum Impact• Airport Noise Stage 4 with 10dB Margin

Gulfstream Proprietary Information

Supersonic Technology Development

Conduct basic research into reducing the impact of sonic boom on people and the environment to enable regulatory change for supersonic flight overland, domestically and internationally

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ΔPre

ssur

e / F

rees

tream

Pre

ssur

e Wind Tunnel

Overflow CFD

Gulfstream Proprietary Information

Sonic Boom SuppressionSonic Boom Suppression

• Gulfstream Quiet Spike™

– Extendable Nose Spike

– Generate Series Of Weak Shocks

– Propagate Parallel To Each Other

– Transform Sharp Crack Into Quiet Whisper Quiet Spike

Without Spike

NASA LaRC UPWT

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Time (seconds)

Del

ta P

ress

ure

(psf

)

ConcordeSBJ w/ No ShapingQSJ w/ Quiet Spike

Gulfstream Proprietary Information

Excellent Correlation & Validation of Sonic Boom Suppression

Excellent Correlation & Validation of Sonic Boom Suppression

Near-field signature 95 ft. below aircraft

Quiet Spike™ Flight TestQuiet Spike™ Flight Test

Photo: NASA Dryden Flight Research Center

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-10 0 10 20 30 40 50 60 70 80 90 100Xcone ~ feet

ΔP/

P

Probing Sig. #10 at D-av = 95 ft.3-D Hybrid CFD - Interpolated to #10

Comparison of CFD-Predicted vs. Measured Near-field Signature

Gulfstream Proprietary Information

Preliminary Outdoor Acceptability ResultsNASA F-18 Low Boom Flight Test – October 2005

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PLdB

w/o

U-w

ave

AcceptabilityAcceptable 24/7

AbsolutelyNot AllowableMarginal

Acceptable Day Time Not Acceptable

< 70

PLd

B

50% Acceptance95% AcceptanceLinear (50% Acceptance)Linear (95% Acceptance)

y = 5.7889x + 54.646R2 = 0.3195

95% Acceptance

y = 8.7209x + 51.731R2 = 0.7576

50% Acceptance

Boom Sound Levels

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HSCT Concorde SBJ QSJ shaped QSJadvanced

QSJadvanced+

ConfigurationdB

PLdBdB(A)

Talking

City Traffic

dB(A)>35dB Reduction

Boom Sound Levels

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HSCT Concorde SBJ QSJ shaped QSJadvanced

QSJadvanced+

ConfigurationdB

PLdBdB(A)

Talking

City Traffic

dB(A)>35dB Reduction

Flight test results validated independently

via SASSII outdoor simulator testing

Flight test results validated independently

via SASSII outdoor simulator testing

Gulfstream Proprietary Information

Global Impact AssessmentGlobal Impact Assessment

Low Boom Signature Robust in Non-Standard

Atmosphere

Low Boom Signature Robust in Non-Standard

Atmosphere

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Time (sec)

Del

ta P

ress

ure

(psf

)

St. Helena Island (summ) 58.6 PL(dB)Oimakon, Russia (wint) 69.5 PL(dB)Std. Atm. 66.8 PL(dB)

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110

PL

(dB

)

N-wave, 90 deg hdg, MN-wave, 90 deg hdg, JuN-wave, 90 deg hdg, SN-wave, 90 deg hdg, DN-wave, 270 deg hdg, MN-wave, 270 deg hdg, JuN-wave, 270 deg hdg, SeN-wave, 270 deg hdg, DeCase 432, 90 deg hdg,Case 432, 90 deg hdg,Case 432, 90 deg hdg,Case 432, 90 deg hdg,Case 432, 270 deg hdg,Case 432, 270 deg hdg,Case 432, 270 deg hdg,Case 432, 270 deg hdg,

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Perc

eive

d Lo

udne

ss (P

LdB

)

0 20 40 60 80-20-40-60-80Latitude

QSJ, Std. Atm.: <70 PLdB

Concorde, Std. Atm.: >105 PLdB

Gulfstream Proprietary Information

Summary

• Continued Market / Industry Interest in Future Supersonic Concepts

– Supersonic Overland Flight is Required

– Manage Environmental Design Requirements for Success

• Promising Research Results in Sonic Boom Suppression

– Validated Quiet Spike Technology

– Acceptable Noise Level Achieved Through Low Boom Shaping

Quiet Spike Video

Gulfstream Proprietary Information

Questions ?Questions ?