•f ..

. COpy

CONFIDENTIAL

NACA - Langley

8- BY 14-FOOT GUST TUNNgL

The gust tunnel is unconventional in character. The aj)oaratus con­sists of a cata~ult for launching dynamically scaled models in steadyflight, a .tunnel to provide a jet of air of known characteristics tosimulate a gust. curtains for stopping and catching the model aftertraversin~ the gust, and suitsble instruments for recording the re­actions of the models in the simulated gust. Supplementary equipmentincludes a traveling dynamic balance for determining the lift, drag,.md moment of restrained models and the aerodynamic forces acting onthe component parts of an airplane in unsteady flow. The bust tunnel?rovides means of determining the reactions of dynamically scaledmodels in known gusts under closely controlled conditions and may beused as follows: To calibrate airplanes which have been used as in­struments in investigations of atmospheric turbulence or upon whic~ asignificant amnunt of gust load data has been obtained; to testsoecial models for studying unsteady flow phenomena; to predict thegust load factor for new designs; and to test gust alleviation de­vices. The traveling dynamic balance will be used to verify theo­retical work and to determine the behavior in unsteady flow for caseswhich theoretical analysis is either impractical or nf doubtful value.

The pertinent characteristics of the gust tunnel are as follows:

(1) Characteristics nf catapult

TyoeSoeed range, mphAccelerating distanceModel size handledModel weight, maximum

(2) Characteristics of tunnel

TunnelLocationTypeJet type

Jet shapeContraction ratioHorsepowerVelocity range, mphOperating oressureEnergy ratioScreen lossesReference

Comj)ressed air30 to 10050 feet7-foot span maximum40 pounds

8- by 14-foot gustLMALReversible single returnCpen throat, adjustable

angleRectangular, 8 by 14,feetNegative 2.9675o to 14Atmospheric0.02 (approx.)10 q (approx.)None

CONFIDENTIAL

-- ,.. ••

C6N FIDENT rIlL

- 2 -

(3) Primary recorded data (free model tests)

Time histories Acceleration, pitch angleand vertical displace-ment

Velocities Forward speed and gustvelocity

(4) Traveling dynamic balancE>

Maximwn forward speedModel sizeNatural frequency of

balance1t<3 e.surcments

(Copied 5/23/4-5, emp)

(Copied a/20146,jss)

60 mph3-foot span

130 cycles per secondLift, drag, and moment

CONFIDENT rIlL

- ,

TunnelLocationTypeType model

Jet typeJet shape

Jet dimensions

Jet lengthContraction ratio

Operating uressurerange

Hor sepower

Dynamic pressurerange, 1b/rt2

Speed range, mph~~ch number range

Turbulence factorEnergy ratio

ReferenceRemarks

COPY

CON FIDEl,T IAL

NACA - Langley

24-INCH HIGH-SPEED TUNNEL

24-inch high-speedUt'l.LInduction, nonreturnTwo-dimensional and three-

dimen s i onalCloGed throatCircular cross section with

large chord flats24-inch diameter (18 inches

between flats)Approximately 16 inchesThis term is not applicable as

for conventional wind tunnels.Air flow is induced from theatmosphere.

Atmospheric.Driven by an induction jet;

maximum operating conditionsare an induction jet chamberpressure of 180 usi and a dis­charge rate of 55 lb/sec.

55 to 785155 to 6950.2 to 1.0 tunnel empty (speed

limited by choking conditionsfor model tests)

1.1 (approx.)2.05 (maximum) Decreases with

decrease in Mach ~umber. Notstrictly comparable with con­ventinual 'IJ'ind tunnel s.

TR 646 and ACR L4L07a

(Copied 5/22/45, emp)

(Copied 8/20/46, jss)

CONF IDENT IAL

•COPY

COllFIDENT IAL

NACA - Langley

8-FOOT HII}H-SPEED TUNNEL

TunnelLocationTypeType model

Jet typeJet shapeJet dimensions

Jet lengthContraction ratioOperating pressure

rangeHorsepowerDynamic pressu~e

range, lb/ftVdoci ty range. mDh!.!.ach number range

Turbulence factor

Energy ratioReferenceRemarks

8-foot high speedLMALSingle returnTip-supported or three-

dimensinnalClosed throatRound (with vertical flats)8-font diameter (7 feet 7 inches

between flats)1.8 diameter9·0

Atmospheric16,000

o to 800o to 750o to 1.00 tunnel empty (speed

limited by choking conditionsfc'r model tests)

1.01 to 1.06 (based on hot-wiremeasurements of longitudinaland lateral turbulence)

7.5None

(Copied 5/22/45, emp)

(Copied 8/20/46, jss)

CONFIDENTIAL

COPY

CONFIDENTIAL

NACA - Langley

16-Foo'r HIDB-SPEED TUNHEL

TunnelLocationTypeType model

Jet typeJet shapeJet dimensions

Jet lengthContraction ratioOperating pressure

rangeHorsepowerDynamic pressure

range, lb/rt2

Velocity range. mphMach number rangeTurbulence factor

Energy ratioReferenceRemarks

16-foot high speedLMALSingle returnTip-supported or three-

dimensionalClosed throatCircular (with vertical flats)16-foot diameter (15 feet

between flats)24 feet (1.5 diameter)13.4

Atmospheric16.000

o to 540o to 525o to 0.70Low but not quanti tati.vsly

dete rmined9.5None

(Copied 5/22/45, emp)

(Copied 8/20/46. jss)

CONFIDENTIAL

TunnelLocationTypeType model

Jet typeJet shapeJet dimensions

Jet lengthContraction ratio

Ooerating pressurerange

Horse1?O\verDynamic pressu2e

range, 1b/ftVelocity range, mphMuch number range'l'urbulence factorZnergy ratioReferenceRemarks

CO?Y

COUFIDENrIAL

NACA - Langl..~,

1~DEL SUPERSONIC TUm~EL

Model supersonicLrfi.ALViract action, nonreturnrhree-dimens~onal or two-

dimenr.ionalClosed thr'latRectangula r7-1/2 inches wide by 7-1/2 to

9 inches high1-1/2 ti.mes width (approx.)100 to 1 for smallest nozzle

minimum and 70 to 1 forlargest nozzle minim~~

Stream pressures from 1/5 to1/3 atmospheric pressure

1000

1200 to 14001000 to 12001.35 to 2.0Not determined1,6None

(Copied 5/22;45, emo)

(Copied 8/20/46, jss)CON FIDF.JU IJIL

COpy

COKFIDErJrIAL

NACA - Langley

'tECTPlJ1ULAR HIGH-SPEED TUNNEL

TunnelLocationyee

Tyoe modelJe';; typeJOet shapeJet diI:1ens ions

Jet lengthContraction ratio

Operating pressurerange

Horsepower

Dynamic oressurerange, 'lb/rt2

Velocity range, mphYach nu~ber range

Turbulence factorEnergy ratio

Reference

Remarks

(Cooied 5/22145, emo)

(Cnpied 8/20/1+6, jas)

Rectan~ular high s)JeedLlMLInduction, nonreturnTwo-dimen sienalClosed throatRectangular!~- by l8-inch (4-inch dimension

fixed, l8-inch dimensionvariable)

10 inches (apprnx.)This term is not applicable as

for conventional wind tunnels.Air floVi is induced from theatmosphere.

AtmosohericInduction type tUlli1el utilizing

a maximum of 15 pounds of airper second &t pressures up to290 osi in an annular nozzledownstream of test sectinn.

55 to 910155 to 915~)Jproximately 0.2 to 1.4 (choking

prevents testing at ~ach numbersin the neighborhood of 1)

Has not been dete rmine dAporoximetely 1.5. This term

varies over the Mach numberrange and is not strictlycomparable with conventionalwind tunnels.

stack, John: CompressibilityEffects in AeronauticalEngineering. NACA ACR, 19h1

COHFIDENT TAL

•COpy

CONFIDENTIAL

lJACA - Lallr;ley

FDLL- SCALE TlJ1',"J'j EL

&:

1/15-SCJo.LE !lODEL OF FULL-SCALE TUNNEL

Full-scaleTunnel

LocationTypeType modelJet typeJet shapeJet dimensionsJet lenr;thContraction ratioOperating uressure

rangeHorsel;10werDynamic ure s sure

ranr;e, Ib/rt2

Ve 1oc i ty ranr;e, mohMach number ranr;eTurbulence factorEnergy ratinReferenceRemarks

(Copied 5/23~~5. emp)

LMALDouble returnThree-dimensionalOpen throatZlliotical60 by 30 feet56 feet4.93

Atmospheric8000

1.5 to 3625 to 1180.03 to 0.161.12.84rR 459

COllFIDENT IAL

1/15-scale mod01of full-scel03

LMALCouble rei;urnThree-dimensionalOpen throatEllipticalU by 2 feet3.73 feet4.93

Atmospheric30

o to 195 to 85o to 0.111.21.50TR 478Not equipped with

balance

COPY

CONFIDENTIAL

NACA - Langley

INDUCTION AERODYNAMICS LABORATORY

LocationFloor area for test setupsTest cellAir su~ply

L1.y.L100 feet by 120 feet22 feet by 22 feet by 118 feet3- to lOGO-horsepower blowers

Volume Volume Pressureblower & blower &pressure pressure blower &

blower in blower in compressor

parallel series in series

--_.. ---- .---

~----_.- ----

---- ---- ---.

182,000 ---- ----145 ---- ----150 ...... .---

---- 35,000 1,,800

---- 970 2,900

---- f:i:IJ 1,220

CompressorPressureblower

Volume rblower

*Capacity, C. F. M. 85,000 44,000 13,800Pressure above

1b/tt2atmospheric, 265 530 2,116Pressure below

1b/tt2atmospheric, 240 425 1,058

Capacity, C. F. M. 128,000 65,000 ---Pressure above

atmnsnheric, 1b/rt2 89 145 ----Pressure below

atmospheric, Ib/rt2 87 141 ----Ca~eity, C. F. M. 45,000 25,000 9,000Pressure aboveatm~spheric, Ib/rt2 325 655 2,350

Pressure below 2atmosnheric, Ib/ft 285 500 1,110

Maximumpressure

Maximumflow

Rated

__---.......1 ~__~_.....L.___..:.._._._ ____1___.....L_ 1

.Flow quantities given are corrected back to the temoerature and ~ressure at the entrance to the IblO'.'1er. I

,L-..__------------------------

,.(Cooied 5/23145, emTI)I,,~_; - IJ,~ jss) CONFIDENTlJIL

•COpy

CONFIDENT IAL

NACA - Langley

TVIO-DIMEl>;SIONAL LO'N-TURBUL£NCE TUNNEL

TunnelLocationTypeType model

Jet typeJet shapeJet dimensionsJet lengthContraction ratioOperating orassure

rangeHorseoowerDynamic uressure

range. Ib/ft2Velocity range. mph~~ch number rangeTurbulence fact6rE:nergy ratioMaximum Reynolds numberReferenceRemarks

(Copied 5/23/45. emp)

(Copied 8/20/~6. jss)

~vo-dimensional low-turbulenceLMALSingle return~o-dimensional (limited three­

dimensional models such asnacelles on ,ving sections)

Closed throatRectangular3- bJ 7-1/2 foot7-1/2 feet18:1

Atmos."heric195

o to 65o to 159o to 0.2151.03.01,48 x 106 per foot of chordNone(a) Standard airfoil character­

istics tests are made with24-inch chord models. Maxi­mum lift characteristicscannot be obtained withmodels haVing a chord largerthan 36 inches. Drag charac­teristics at low lift coef­ficients can be obtained withmodels having chords up to100 inches.

(b) Turbulence of the air streamof this wind tunnel is verylow. Fluctuating componentsof velocity are a fewhundredths of 1 percent.

CONFIDENT IAL

• COpy

CONFIDENTIAL

NAC}. - Langley

TWO-DI~ENSIONAL LOW-TURBULENC3 PRESSURE TU1~iEL

Tunnel

LocationTypeType model

Jet ty,)i3Jet shaneJet dimensi on sJet lengthContraction ratioO,,"rating pressure

rangeHorsepower~rn~~ic uressure. range, lb/rt2

Velooity range, mph

Mach number range

Turbulence factor&nergy ratio:.laximum Reynold s numberReferenceRemarks

(Copied 5/23145. emp)

(Cooied 8/20/116, j s s)

Two-dimensional low-turbulencepressure

LMALSingle returnTwo-dimensional (limited three­

dimensional models such asnacelles on wing sections)

Clo sed throatRectangular3- bJ 7-1/2 foot7-1/2 feat17-1/2 :1

1 to 10 atmospheres2000

o to 670o to 300 (one atmosohere)o to 220 (four at~o;oheres)o to 160 (ten atmospheros)o to 0.4 (one atmosohere)o to 0.3 (four atrr,ospheres)o to 0.2 (ten atm~soheres)

1,0

3.5 614 x 10 per foot of chordNone(a) Standard airfoil character­

istics tests are made ~ith

24-inch chord models. h~xi­

mum lift characteristicscannot be obtained with modelshaving a chord larger than36 inches. Drag charactor­istics at low-lift coef­ficicmts can be obtain"d wi.thmodels having chords up to100 inches.

(b) Turbulence ° the air streamof this wind tunnel is verylow. Fluctuati ng; C omponont sof velocity are a fewhundredths of 1 oercent.

CONFmC:UTIAL

• •

TunnelLocationTypeType modelJet typeJet shapeJet dimensionsJet leng;thContraction ratioOperating pressure

rangeHorsepowerDynamic press~e

range, Ib/ft

Velocity range, mph

Mach number range

Turbulence factorBefore installation

of screen

After installationof screen

F.nergy ratioReferenceRemarks

(Copied 8/20/46, jss)

COPY

CONFIDENTIAL

NACA - Langley

19-FOOT PRESSURE TUNNEL

19-foot pressureLMALSingle returnThree-dimensionalClosed throatRound19-foot diameter1-1/2 diameters8:1

1 to 2-1/3 atmospheres8000

12 to 175 (1 atmosphere)15 to 250 (2-1/3 atmospheres)70 to 260 (1 atmosphere)50 to 210 (2-1/3 atmospheres)0.09 to 0.34 (1 atmosphere)0.07 to 0.28 (2-1/3 atmospheres)

1.03 from tests of 8-inch sphere(1 atmosphere)

j;2 cr~ 0.003,.i!...- 0.006 from hot-

U Uwire measurements (1 atmosphere)

No data available for 2-1/3 atmos­pheres

No data available for 1 atmosphereNo data available from tests of

8-inch spheres (2-1/3 atmospheres)

/.'- r-_2 .-2.l£.lL.. \/vU 0.002, ---U-- 0.005 from hot-

wire measurements (2-1/3 atmos­pheres)

7.5None published

CONFIDENTIAL

• COpy

CONI' !DENT I.~L

NACA - Lang;ley

20-FOOT ORO PELLER RESBft_RCH Tum:EL

TunnelLocationTypeType modelJet G:>'peJet shapel.Tat dimensionsJet leng;thContraction ratioOperating pressure

ra.ngeHorsepowerDynamic nressure. - I 2rerlge, Ib .ftVelocity range, mohIi",c h number rangeTurbulence factnrEnerg.j' ratioReferenceR:.~marks

(Copied 5/23/h5, emp)

(Copied 8/20/46, jss)

20-foot propeller rese~rch

LMALDoubl" returnThree-dimensionalOpen throatRound20-foot diameter1.75 diameters7.97

Atmospheric1800

o to 31o to 110o to 0.141.21.39TR 300

CONFIDENT IAI.

Calculated assumingener$Y ratio equal to8-1/4 to 1 Iltmospheroprassure at throat

TunnelLocationTypeType modelJet typeJot shapeJet dimensionsJet lengthContraction ratinOperating pressure

rangeHorsepowerDynamic pressu2"

range. Ib/ftVelocity range. mphMach nQ~ber rangeEnergy ratioTurbulence factorReferenceRemarks

(Copied 5/22;45. emp)

(Copied 8/20/46. jss)

CCpy

CONFIDENTIAL

HACA - Langley

FLUi'TE:R TUNNEL

FlutterillUSingle returnThree-dimensionalClosed throatCircular4-1/2 foot diameter9 feet8.93

o to 1.8 atmospheres (aoprox.)1000

o to 812 1o to 975 "-o to 1.00,'/8 I

jNot known

1. 1wo mobile interchangeabletest section s:(a) Four-component hydraulio

balance test section(b) Flutter test section.

17 viewing portholes2. Charge cooled by two alter3ate

methods:(a) Zxchanging portion of

charge for atmosphericair

(b) Passing portion chargethrough heat exchanger

3. Entire tunnel designed tohold 0 to 1.8 atmospherosof Freon 12 as testing medium.

CONFIDENTIAL

00PY

CONF IDENT IAL

NACA - Langley

AT~OSPflliRIC WIND TUNNEL

TunnelLooationTyDeType model

Jet typeJet shapeJet dimen s ionsJet lengthContraction ratioODerati.n!'; pressure

rangeHorsepowerDynamic Dressu£e

ran!';e. lb/ftVelocity ranf,e. mphMach number rangeTurbulence factorEnergy ratioRefer'3nceRemarks

(Copied 5/22~~5. emp)

(Copied 8/20/46, jss)

Atmospheric windLMALSingle return - horizontalThree-dimensional, two-

dimensional, and partial­span (reflection plane)

Closed throatRectangular7 by 10 feet11 feet4.0

Atmospheric200

o to 16.37a to 80o to 0.111.61.4TR 412 and TR 664Tunnel equipped with six-component

balance ~~d scale system

CON FIDENT IftL

• COpy

CONFIDENTIAL

NACA - Langley

300-~lILE-PER-HC'lJR7- BY lO-FOOT ~'!IN_ TUNNEL

HIGH-SPEED 7- BY 10-FOOT :lIND TUIiNEL

A feature of both tunnels is cnntainedin a rQmotely controlled surveyapparat;us which is constructed as (.ninherent part of tho tunnels andwhioh permits th" r"pid explor tionof air flow behind models. Bothtunnel s equipped with six-componentbalance systems. rhe high-sp~ed

tunnel is to be provided with enadjustable tast section.

Tunnel

Loceti.onTyooType models

Jet tyeeJat shenaJat dim8nsionsJet lengthCnntrp.ction ratioOpertiting ~ressure

ren~e

HorsepowerDynamic pressure

rang"', 'lb/rt2

Velocity range, mphMach n1nnber rangeTurbulence factorEnergy ratioRoferenceR"mRrks

(Cnpied 5/23145, emo)

(Copied 6/20~~6, jss)

300-mile-per-hour7- by 10··foot

LMALSingle returnThree-dimensional.

two-dimensional.and semispan

Clnsed thrnatRectangular7 by 10 feet15 feet14

Atmospheric1600 .

o to 200a to 300o to 0.40

7

High-speod 7- by10-font (und~r

construction)LW,LSinble returnThree-dim~nsional,

tvlo-dimonsional.and semispan

Closed throatRectangular7 by 10 feet15 feet14

Atmospheric10,000

COl:FIPENTIAL

•

TunnelLocationTypeTyoe modelJet tyueJet shapeJet dimensionsJet lengthContractinn ratioOperating pressure

rangeHorsepower

Rated5-minuta rating

Dynamic pressureranga, 'lb/rt2

Velocity range. mphMach number rangeTurbulence factorEr..ergy ratioRefarenceRamarks

(Copied 5/22145, emp)

(Copied 8/21/46, jas)

COpy

CONFIDENTIAL

NACA - Langley

FREE-FLIGHT TUHNEL

12-foot free flightLMA.LOpen returnThree-dimensional d)~amic

Closed thrnat12-sided polygon12-foot (across flats)1.25 diameters4

Atmospheric

280570

o to 9o to 60o to 0.081.60.5TN 810Free-flyin~ remot01y controlled

dynamic models are tested inthe tunnel. The longitudinalaxis of the test section ofthe tunnel can be tiltedthrough a range of anglescorresgondi.ng to 150 climband 45 glide. The tunnelis housed in a 60-foot steels~here which provides uniformreturn passage at all anglesof tilt.

CON FIDENT 1AL

TunnelLocationTyne1'Y1Je of mode 1

Jet tyooJet shapeJet dimensionsJet lengthContraction ratioOperating pressure

rangeHorsepowerDynamic pressu2e

range, Ib/ftVelocity range, mph!~ch number rangeTurbulence factor611ergy rati 0

ReferenceRemarks

(Copied 5/22;1.6. emp)

(Copied 8/21/46, jss)

COpy

CONFIDEN'r IAL

NACA - Langley

4- by 6-fnotLMALSingle return - verticalThree-dimensional, ~NO-

dimensional, and J)artial­span (reflection olane)

Closed throatRectangular4 by 6 feet4.5 feet3.37

Atmo s ahe ric50

o to 15o to 76o to 0.111.931.4TR 387 and TN 73L~Tunnel equipped with three­

component balanoe Bnd scalesystem

CONF IDENT 1I\.L

COpy

CONFIDENT IAL

NACA - Langley

20-FOOT FREE-SPINNING WIND TUNH~L

&

15-FOOT FREE-SPINNING 1;100 Ttn~NEL

Tunnel

Location'fJ--p9

Type model.Jet type,let shapeJet dimensions

Jet lengthContraction ratioOperating pressure

rflllgeHorsapower

Rated5-minute rating

Dynamic pressu2erange. Ib/ft

Velnc i ty range. mphMach number rangeTurbulence factorllnergy ratioRefarenceRem'lrks

(Copied 5/23/45, emp)

(Copied 8/21/46, jss)

20-foot freespinning

LMALVertical with

annular returnDynamicClosed throat12-5ided polygon20 feet across

flats1.5 diE,m"te r4.0

Atmospheric

4001300o to 10

o to 62o to 0.08

CONFIDENT IAL

15-foot freespinning.

LM.~L

Vertical withoutdb·ect return

Three-dimens ionalClosed throat12-sided polygon15-feet across

flats1.26 diameter2.9

Atmospheric

150260o to 4

0 to 400 to 0.05

0.35'rR 557

22 feet9

•

TunnelLocationT~

TYlJe models

Jet typeJet sharesJet dimensions

Jet lengthContraction ratio0gerating pressure

rangeHorsepnwerDynamic pressure

range, ·lb/ft2Velocity range, mphMIlch number rangeTurbulence factorEnergy ratioReferenceRemarks

(Copied 5/23/45, emp)

{Copied 8/21/46, jss)

COpy

CCNFIDENTHL

NACA - Langley

STABILI'£Y Till'NEL

stabilityLtfALSingle returnThree-dimensional, two-dimensional,

and semispanClosed throat (interchangeable jets)Square Row1d Rectangular6 by 6 feet 6.3-foot 6 by 2-1/2

diameter feet22 feet 6 feet10.5 21.6

Atmospheric Atmospheric Atmospheri600 600 600

o to 125 0 to 125 o to 350o to 220 0 to 220 o to 360o to 0.29 o to 0.29 o to 0.471.04 1.04 1.05.0 5.0 17

An unusual feature of the 6- by 6-footsquare test section of the stabilitytunnel is the fact that the sides ofthe test section are adjustable. rhesides can be adjusted to differentradii of' curvature so that models callbe tested in curved flow simulatingflight in curved paths of differentradii.

The 6.3-foot diameter round tes~ sectionis provided ~~th rotating vanes. Th~

rate of rotation can be adjusted as ~n

give a predetermined ~rist to the airstream. In this way, different ratesof roll can be simulated while themodel is stationary and the differentaerodynamic forces can easily bemeasured by the balance system.

CONFIDENT IAL

• COpy

CONFIDENTIAL

NACA - Langley

INSTRm.~T RESEARCH WIND TUNNEL

TunnelLocationTyoe1'ype modelJet typeJet shapeJet dimensionsJet lengthContraction ratioOpe~ating pressure

rangeHorsepowerDynamic pressu~e

range, Ib/ftVelocity range, mphMach number rangeTurbulence factorEnergy ratioReferenceRe'llarks

(Copied 5/22/45. emp)

(Copied 6/21/46, jss)

Instrument researchLLiALOpen returnThree-dimensionalClosed throatRound15-inch diameter28 inches20:1

14.7 to 11 Ib/in2 (approx.)300

,.6 to 520 (estimated)40 to 500 (estimated)0.052 to 0.65 (estimated)Not known3 (estimated)NoneEspecially built for testing

small components of instru­ments to obtain the charac­teristics, from an instru­mental point of view, nsaffeoted by the air streamvelocity and direction.

CONFIDENT IAL

COpy

CONFIDElII'IAL

NACA - Langley

LOW-VELOCITY IRSTRm~NT TumlEL

Tunnel

LocationTypeTyps modelJet typeJ~t shapeJ~t dimensionsJet lengthContraction ratioOocrating pressure

rangeHorseuowarDynamic ore s su~e

range, lb/rtVelocity range, mph,Iach llumber rangeT~rbuldnce factorEnergy ratio.ReferenceR,-"m.arks

(Copied 5/22/45, emp)

(Copied 8/21/46, jss)

Low-velocity instrument (oldgust tunnel)

L1lALOpen returnThree-dimensional (instrument)Cloc.ed throatSquaro36 inche s by 36 inche s36 inches2.6:1

Atmospheric

o to 35 (estimated)

Not knownNot knownNone'l'his tunnel Vias built by

remodel ing the old gusttunnel. It is shared withthe Fluids and Gas DyllamicAnalysis Section. The testsection and diffuser sectionare removable and inter­~hangeable with a cascadesection belonging to FGDA.It is used by InstrumentRElsearch Di visi on for testsof low-velocity instruments,including hot-wire anemometersand other wind direction andvelocity instruments.

CONFIDENTIAL