Army Aviation Digest - Aug 1962

8/12/2019 Army Aviation Digest - Aug 1962

1/52


2/52

UNITE

OF ARMY AVIATION ODCSOPSOF THE ARMYBrig Gen Delk M. Oden

5 RMY VI TION1GESJAUGUST 962 VOLUME 8 NUMBER 8

U. S. ARMY AVIATION SCHOOL CONTENTSBrig Gen Robert R. Williams

U. S. ARMY AVIATION SCHOOLCol Warren R. Williams

STAFFCapt Joseph H. PooleFred M. MontgomeryRichard K. TierneyWilliam H. SmithM/Sgt Thomas M. langDiana G. Williams

EDUCATION AND LITERATURE DIVPierce l WigginWilliam E. CarterJames E. Coleman

LETTERS . . . . . . . . . . . . . . THE CHINOOK, Maj John C GearyTHE ARMY AVIATION STORY, PART II I, M/Sgt Thomas M. LangFIXATION, Pierce L. Wiggin . . .ABOVE THE GAUNTLET , Capt Paul B Malone, III . CAUTION: JUNGLE OPERATIONS , Capt Alexander R Zenz . TWX . . . . . . ARMY OIL ANALYSIS PROGRAM, Lt Robert C McGee, Jr. .. . WHAT HAPPENED TO HANGAR FLYING? Capt Robert L. Oliver . WHAT IS AN AIRCRAFT ACCIDENT PREVENTION SURVEY?Capt Joseph H. Masterson . .. . . . . .FALCON S NEST . . . . . . WHAT CAN YOU DO? . . . . .. ..CRASH SENSE . . . . . . . . .

The mission of the U. S. ARMY AVIATION DIGEST is to provide information ofoperational or functional nature concerning safety and aircraft accident prevention trainimaintenance operations research and development aviation medicine and other related daThe DIGEST is an official Department of the Army periodical published monthly unthe supervIsion of the Commandant U. S. Army Aviation School. Views expressed herare not necessarily those of Department of the Army or the U S. Army Aviation SchoPhotos are U. S. Army unless otherwise specified. Material may be reprinted giving creto the DIGEST and to the author unless otherwise indicated.Articles photos and items of interest on Army Aviation are invited. Direct communition is authorized to: EJi tor- in-Chiej U S. Army Aviation Digest Fort Rucker AlabamaUse of funds for printing of this publication has been approved by HeadquartDepartment of the Army 27 November 1961.To be distributed in accordance with requirements stated in DA Form 12.


3/52

This unit is starting a file onU. S. ARMY AVIATIONRequest we be fur

one copy of any DIGESTafter January

Further we suggest future ediof the magazine be pre

-inch holes to fitstandard three ring loose leaf

WILLIAM F. MARTINl i Lt, InfAdm Off Available back issues areway. DA Forms 12 and

should be obtained fromAG publications center andto request distribution of

DIGEST. After requestingmany copies monthly as youon the form, submit ityour local AG publicationsHe ll do the rest. De

instructions are on theof the DA Form 12. NaGuard and Army Reserveuse the same method of re

Regarding prepunching of thezine, unfortunately t hi su l d add to our alreadyAlso these holes

sometimes upset the inof material. Bear

us and use your office per

Sir:While on a recent flight I hadthe unhappy experience of hav

ing to listen to a fellow ArmyAviator flying a L-26 twin-engine aircraft monopolize a vitalradio channel (and the time ofan FAA radio station) for TENcontinuous minutes in a most unnecessary and unprofessionalmanner.

Contacting Millville Radio at1750Z he explained that al though he originally filed FtMonmouth as a passenger stop,a passenger had been on theground longer than expected sohe wanted to close the originalflight plan as of 1640Z and openanother VFR . flight plan as of1740Z destination Cairns AAF;direct Anacostia direct RaleighDurham direct Cairns ; 6: 30 en route; 5: fuel aboard; passenger stop at Anacostia and a fuelstop at Raleigh-Durham includedin total time; 2500 feet to Raleigh - Durham 4500 feet toCairns pilot 2 - 1; 3 personsaboard.

You can imagine the confusionand delays on the frequency asthe pilot tried to get this mazeof information across to the un prepared FAA operator. Reactions of those of us listening onthe channel were varied. Thesituation was both embarrassing

E

and dangerous. During the timethe channel was tied up, at leasttwo pilots w r delayed inmaking routine position reportsand one pilot tried to tell someone he had an emergency. Asafer more efficient method offiling is available to all aviators.The following special notice islisted in the 10 October 61 Airman's Guide:

FILE FLIGHT PLANSBEFORE TAKEOFF

Pilots are urged to file VFRflight plans in person or by telephone prior to departure. Radioshould be used for filing flightplans only when it is impossibleto file in person or by telephone.This procedure i necessary inorder to avoid congestion on thealready busy air-ground communications channels. he s echannels should be reserved foressential inflight communications. All pilots will benefit byfollowing this practice.

Radio should be the last re sort, even if the other methodsare not the most convenient ormay be time consuming. f it isutilized, the aviator must realizethat he is infringing on an al ready overcrowded channel.

As professional aviators weare expected to use the safest most efficient methods available


4/52

AUGUST 1962

in all operations. Let's file onthe ground

UNHAPPY PILOT VerilySir:

I am writing in response toyour request for new articles tobe published in the U. S. ARMYAVIATION DIGEST.

In reading the DIGEST, I amsure many of us pay particularattention to the TWX and CrashSense articles, but this writercannot help but think that, al though many of these "Heads Upand Locked" situations are certainly a part of the human errorfactor, we in the Army aviationprogram must certainly haveaviators, mechanics, tower operators and the like who have atone time or other committeddeeds which have contributedgreatly in the prevention of accidents or incidents, therebyplacing these individuals in the"Heads Out and Unlocked" category.

Isn't it about time Army Aviation gave recognition to theseindividuals who have preventedor helped in the prevention ofcostly accidents? Are we becoming so one way in our thinking that only the bad things thathave happened are printed?What about the aviator who losthis tail rotor with the general onboard and then successfully executed a safe landing, therebysaving the aircraft, the pilot anda v e r y valuable passenger?Doesn't he (the aviator) deservea pat on the back?

The Navy and the Air Force,in one of their monthly publications, give recognition to personnel of their forces for acts asstated above. Let us do thesame

As a proposal I suggest a pagebe set aside each month in theDIGEST, under the title of "Con-gratulations to or

2

"AA Professionals," or any titleyou desire, but let's let thesepeople be heard of.

PAUL W. FRANCECaptain, TCOffice of theSenior TransportationAdvisor, KMAGAPO 102,San Francisco, Calif.

Giving such recognition is aproblem. Accident and incidentreports, ultimately funneled intothe U S Army Board for Avia-tion Accident Research, form thebasis for TWX and Crash Sensematerial.

Unfortunately, there is no re-porting system for accidents andincidents prevented. In obtain-ing such information we mustrely on readers s Uch as yourself,unit commanders and unit safetyofficers. Regretably, few such((well dones are submitted.

Those that are received mustbe verified in some manner. Ac -cident and incident reports canin most cases be accepted at facevalue since they report the de-tailed findings of an impartialinvestigation which works toprevent similar future occur-rences. An account of a {{welldone, although written with thebest motives, usually representsthe view of one person, lackscompleteness in detail, and can-not be easily verified for exact-ness.

In the past, some ((well donesreceived would have been em-barrassing to the recipient, rath-er than complimentary, after allthe facts were known. A n ex -cellently handled forced land-ing, for example, was found tobe caused by failure to check theoil filler cap on preflight. Sub-stantiated by a unit commander,operations officer, or unit safetyofficer, many worthy ({welldones could be published - ifsubmitted.

Sir:Your warning to crash rescue

crews, page 42 of the April 1962issue, is to the point.

May I suggest you furtherconsider the effects of varioushead positions on the patency ofthe respiratory airway, in un conscious accident victims. Respiratory obstruction may bethe cause of respiratory failureRecovery, therefore, may be instituted more by the positioningfor artificial respiration, than byits actual administration.

Too often an injured and unconscious person suffocatesfrom the neglect of simple procedures which would have keptopen his breathing channels, hisairway. This may happen whenthe head of a seated casualtyslumps, cutting ' off his wind bythe compression of the structures in his bent neck. Soldierstrapped in vehicles, unconsciousfrom a blow to the head andwithout serious injury, can stildie from neglect of the maintenance of adequate airway duringrescue operations. Or a face-upand unconscious victim chokesfrom the sucking into his lungsof vomitus, or has his throatblocked by loosened dentures, orclosed by the falling back ofslack mouth and throat structures. These things can happeneven after correct immediate action has been taken, and anotherwise rescued man is lefalone on a litter. t can happeni he is transported unattendedand still unconscious, supine andface-up in an ambulance. Thecondition of DOA (dead on ar rival) is then attributed to hiswounds, rather than to theneglect of him. (ARMY Magazine, Mar 62, p 74.)

John B. De HoffColonel, MC92d Field HospitalFort Gordon, Georgia


5/52

HE HC-IB Chinook, thenewest addition to the ArmyAviation inventory, arrived atFort Rucker, Ala., on 7 July forservice testing by the U. S.

Aviation Board. Producedby the Vertol Division of the

Company the Chinook istandem-rotor, twin-turbine

medium transport heliopter. The Chinook's power is

by two Lycoming T55--5 free turbine engines whichan develop up to 4,400 shaftorsepower. A rear ramp perits rapid straight-in loading

nd unloading of troops, vehicles,and cargo.

Although the fuselage is 1shorter than that of the H-21

Shawnee, the payload compartment (30 feet in length to theramp hinge line) is 10 feet longer. Seats are provided for pilot,copilot, crewchief or troop commander, and 33 combat-equippedsoldiers. With troop seats foldedagainst the compartment walls,24 standard pole-type litters canbe accommodated. The unobstructed interior width is 7feet; height, 6 feet. The pay-Maj Geary is Chinook projectmanager U S. Army Transpor-tation Materiel Command.

Major John C Geary

load compartment will accommodate each major component ofthe helicopter-transportable version of the Pershing missile system. Vehicles as large as theM37 34-ton cargo truck can beloaded internally.

The payload compartmentfloor is designed for individualwheel loads up to 2,500 poundsin the vehicle treadway area.The remainder of the floor is de signed for concentrated loads ofup to 1,000 pounds and evenlydistributed loads of 200 poundsper square foot. The floor incorporates 87 flush tie-downrings of 5,000 pounds capacityeach, plus 8 tie-downs of 10,000pounds capacity. In addition,four 5,000-pound capacity ringsare provided on the ramp.

The hydraulically - operatedramp may be left partially orfully open, or may be removedentirely for extra-long cargo,such as pipe sections, antennamasts, etc. Three ramp extensions may be attached at anylateral position for loading vehicles of different wheel tread,and those (like the 106mm BATrifle) that have a wheel on theircenterline. The hatch whichcovers the upper portion of the

O

rear opening slides into the rampwhen the ramp is opened. Hydraulic power for operation ofthe ramp (and other hydraulically - actuated equipment) isavailable, even with the mainengines and the auxiliary powerplant inoperative, from an accumulator. The accumulator isnormally recharged in flight, butmay also be recharged by operating the auxiliary power unit,or by using the integral handpump which is located on theright side near the ramp controlvalve.

The Chinook has a capacity for33 combat equipped troops

3


6/52

AUGUST 962

itter installation

On loading 3Jt ton truck4

Items too bulky to fit withinthe payload compartment canbe transported on the 8-ton capacity external cargo hook. Thehook assembly is stowed withina 3 by 3 foot hatchway locatedamidship between the payloadcompartment floor and the lowerexternal skin. A one-piece trapdoor is hinged to lie flat againstthe floor forward of the hatchway. Since the crewman at thehatchway would normally station himself to the rear of thehatchway for a better view inthe forward direction when approaching a load to be hookedup, the trap door, when opened,is out of his way.

The exterior skin panel, whichcovers the hatchway, is openedby manually turning a handleprovided for this p u r p ~ s e Aparallelogram linkage moves thispanel downward and rearwardso that it rests flat against thebelly of the fuselage to the rearof the hatchway when fullyopened.

When the restraining strap isreleased, the external cargo hookswings downward into its operating position. The tongue of thehook is normally in the closedposition, making it necessary tomerely slip the ring attached tothe load rigging past a springloaded keeper for hookup. It isnot necessary to close the hookafter placing the ring into posi-tion, as is the case with mosthooks currently in use. Thus itis much easier for one crewmanwi hin the helicopter to snag therigging ring with a shepherd'scrook and place the ring withinthe throat of the hook, with noassistance from a crewman onthe ground under the hoveringhelicopter. Safety harness, intercom station, and shepherd'scrook are provided for thecrewman adjacent to the hatchway.The hook assembly is roller-

mounted on a concave curvedbeam which is mounted laterallyon trunnion fittings which attachto the subfloor structure. Therollers are free to move laterallyon the concave curved supporting beam so that side-to-sideswaying of the external loadplaces no rolling moments on thehelicopter for which the pilotwould have to make lateral control corrections. Likewise thetrunnion mounting of the beamprovides fore-and-aft rotationalfreedom of motion to the hookassembly so that longitudinaswaying of the external loadplaces no pitching moments onthe helicopter. This arrangement greatly simplifies the pilot'stask, particularly in turbulent

Cargo hook in stowed positionair, and permits safe high-speedmaneu vering wi h large externalloads.

Normal load release is accomplished hydraulically. In theevent of utility hydraulic systemfailure, release may be effectedelectrically or mechanically.

The Chinook has been referred to as a 2 to 3-ton payloadhelicopter. These payloads reflect two of the mission requirements in the specifications forthe HC-IB, but do not give acomplete picture of the Chinook's capability.


7/52

Rear engine repairst is anticipated that when

conditions limit the takeoff grossweight to that which permitshovering out of ground effect at6 000 feet/ F, the Chinookcan lift a payload of approximately 2 tons with sufficientfuel aboard to fly out a distanceof 100 nautical miles and returnto the takeoff point without re fueling.f takeoff conditions are lesssevere, and the gross weight canbe increased to that which permits hovering out of ground effect at 3 000 feet/ 100 F, thenthe Chinook can lift a pay oadof over 3 tons, again with suffi-cient fuel for a 100-nautical mileradius mission.Maintenance davit and walkway

orward engine repairsWhen ambient conditions per

mit increasing the takeoff grossweight up to the current maximum of 33 000 pounds, the Chinook can hover out of groundeffect at elevations above 3 000feet on a standard day Underthese conditions, payload exceeds 6 tons for the standard100-nautical mile radius missionor over 7 tons i fuel is reducedto that required for a 20-nauticalmile radius of operation. Forferrying (when the entire payload is auxiliary fuel), the Chinook will be able to fly nonstop,a distance of approximately 1 050nautical miles when equippedwi h an extended range kit.

f these payloads are carriedRear ramp elevated

THE HINOOK

externally, added drag is im posed which would increase fuelconsumption and would reducethe distance capabilities citedabove.

The Chinook incorporates features which enhance its abilityto operate under instrument conditions and in light to moderateICIng. These features includewindshield defogging and deicing and engine air inlet antiicing. Blades with fluid deicingare under development and areundergoing test on the rotorwhirl tower at Wright-PattersonAir Force Base. The deicingsystem will be tested on No.4HC-lB currently operating inthe climatic hangar at Eglin AirForce Base. Blades incorporating the deicing system will beintroduced into production as

lectronic and heater compart-ments

soon as development testing iscompleted.

Instrument flying in unstableaircraft is a difficult exhaustingtask. Airplanes, which must always operate at speeds abovestalling, can use aerodynamicforces to obtain stability. However, since helicopters must operate at very slow speeds whereaerodynamic surfaces are ineffective, some other means ofstability augmentation is re quired to obtain good instrument

5


8/52

AUGUST 962

flight capability. The stabilityaugmentation systems (SAS) ,an integral part of the basicflight controls of the Chinook,provide positive dynamic stability about all axes at all forwardspeeds from hovering to maxflight speed. This permits thepilot to execute coordinatedturns without using the directional pedals, and to take bothhis hands and feet off the controls when it is necessary to divert his attention to navigationand communications.

The SAS obtains its intelligence from rate gyros and staticpressure sensors. These intelligence signals are intensified byfully transistorized, miniaturizedamplifiers and move hydraulically actuated extensible links inthe flight control system in amanner which counteracts anytendency of the helicopter todepart from straight and levelflight. Because these links arelocated on the output side of theirreversible lower boost actuators, all of the motion resultingfrom their increasing or decreasing in length is prevented frommoving the cockpit controls andmoves only the upper controls.Thus the pilot is subjected tono annoying control jittering andhas no indication that minutecontrol corrections are being fedconstantly to the rotors. Hesenses only that the helicopterflies straight and level like astable fixed-wing airplane.

The SAS has limited authorityso the pilot can easily compensate for a malfunction whichmight result in a h a r d - o v e ~signal. However, the completedualization of SAS and a selfcentering failsafe feature makethe occurrence of a hard-oversignal very unlikely. A failure inone of the two completely independent systems results in theinstant centering and locking ofthe extensible links of that system. The remaining system,

6

which has sufficient capacity toperform the complete stabilizingfunction, then takes over theentire task.

As stated above, each of thetwo SAS is completely independent. Separate gyros, amplifiers,electronic circuitry, hydraulicpower source and tubing systems, and duplicate extensiblelinks are provided. Malfunctionof either system has no adverseeffect upon the stability of thehelicopter.

The AN/ ASW-12 UniversalFlight Control System will beadapted to provide the automaticpilot functions of heading andaltitude lock.In the design of the Chinook,a major effort has been made toachieve minimum maintenancerequirements and a lack of dependence upon elaborate groundsupport equipment. The toolsfrom a standard Army aircraftmechanic s toolbox were displayed prominently on the wallof the Chinook project engineering department at Boeing-Vertolfrom the start of the project. Thisdisplay constantly reminded designers that these. were toolswith which the aircraft must bemaintained at operating activities.

Access panels have been provided for all components requiring periodic inspection. Thesepanels are hinged or otherwiseattached to the airframe to prevent their being dropped orblown away. Panels which mustbe opened frequently are equipped with quick-opening fasteners. Fluid levels can be inspectedthrough sight gauges. There isno need to remove, wipe, checkand replace several dipsticks.

The requirement for the dailypurging of grease from scores ofgrease fittings has been eliminated on the Chinook. Bearingsin the rotor hub assembly areall oil lubricated, and fluid levels

are apparent by glancing at sightgauges. Upper control rod endsand bellcranks incorporate drylubricant bearings that requireno greasing. By contrast, theH-21 Shawnee has 4 grease fittings on the hubs and uppercontrols that require daily purging.

Integral steps (large enough toaccommodate arctic boots andhandholds, located fore and afton the right side of the aircraft,permit mechanics to reach uppercomponents without using supplemental work stands or ladders. Integral work stands areprovided on each side of the helicopter at forward and rear rotorpylons and at convenient levelfor access to engine controls andaccessories. A walkway along thecrown of the fuselage allows inspection of the interconnectihg. drive shafting, control rods, fluidlines, and wire packs housedwithin the hinged tunnel covers.The walkway also permits maintenance personnel to move between the forward and aft rotorareas without climbing down toground level at one end of theaircraft and back up at the otherend.

Many components requiringperiodic inspection are located atground level: a.c. electrical system distribution center in theforward end of the right-handpod; d.c. distribution center similarly located in the left-hand pod;the rear of the instrument panelthrough the nose access panels;forward and rear landing gearthrough suitably located accesspanels. Fuel servicing is also accomplished at ground level.

Communications equipment,lower controls, heater, utilitywinch, and external cargo hookare accessible from within thecargo compartment. No systemsor components requiring periodicinspection are under the payloadcompartment floor or within thewalls or ceiling.


9/52

The rear loading ramp provides a variable - height workplatform which aids in maintenance and inspection of aft rotortransmission, the accessory gearbox, and the auxiliary powerplant (APP).Provisions are incorporated inthe Chinook for the installationof a hand - powered portablemaintenance davit. This liftingdevice can be installed eitherforward or aft and used for re placement of engines, blades,hubs, upper controls, rear rotorvertical shaft, and all gear boxesexcept the rear rotor box (whichis lowered onto a dolly, usingtwo small hand hoists). Themaintenance davit (probably tobe allocated on .the basis of oneor two per HC-IB unit) eliminates requirements for overheadchain hbists or vehicular cranesfor replacement of major components. Since the heaviest component of the davit weighs lessthan 300 pounds, it can be erected by a crew of four men. Moreover, i f a Chinook is disabled inan inaccessible area due to bladedamage, engine failure, or malfunction of any other component,a replacement assembly - alongwith a davit and repair crew -can be flown to the site in another aircraft.The APP is a T62 gas turbinewhich drives a hydraulic motorpump. The APP is started byhydraulic pressure from an accumulator. f accumulator pres- perating accumulator pump

sure is low (as might result fromthe helicopter standing idle foran extended period), pressurecan be built up using the integralhand pump. Battery power is re quired only momentarily to provide ignition for the APP.With the APP operating, itsmotor/ pump functi9ns as a pumpproviding 3,000 psi hydraulicpc>wer, which is used to drive ahydraulic motor mounted on theaccessory gear box of the rearrotor transmission.To check out the various hydraulic and electrical systems,instruments, and equipment before starting the main turbinesor turning the rotors, hydraulicpower provided by the APP canbe used to drive the accessorygear box (AGB) portion of therear rotor transmission throughthe hydraulic motor. An overriding clutch between the AGB andthe powertrain gearing of therear rotor transmission permitsoperation of accessories Le. alternators, flight control hydraulicsystem pumps, and utility hydraulic system pump) with therotors and powertrain systemheld stationary by the rotorbrake.

Hydraulic motors on the mainturbines are capable of startingengines at any temperature downto minus 65 F without supplementary ground starting carts.Thus the problem of highertorque resulting from partiallycongealed oil coupled with re duced battery capacity at lowtemperature is eliminated. Aswith the APU, battery power isrequired only momentarily toprovide ignition when startingthe main turbine engines.

The drive system includes thetwo T55-L-5 turbine engines,right-angle gear box mounted onnose of each engine, high-speeddrive shaft which connects eachnose gear box to the combiningtransmission (mounted at thebase of the leading edge of

THE HINOOK

the rear pylon), interconnectingdrive shafting that runs aft fromthe combining gear box to the aftrotor transmission and forwardto the front rotor transmission,and these latter transmissionswhich drive each rotor hubassembly.. The drive system is designedto accept the full 4,400 horsepower developed by the two T55-1.. 5 engines at sea level on astandard day. This results in excess drive system capacity (andsome weight penalty) when operating under conditions ofelevated altitude and temperature, which reduce the poweroutput of the engines. However,by providing drive system capacity equal to the maximum poweroutput of the engines, the Chinook has impressive alternategross weight capabilities, as isevident from fhe earlier discussion of its payload capacity un der various conditions. Moreover, by designing initially forthe full power of the engines, theChinook is provided with agrowth capability that can takeadvantage of the increased powerthat will probably be availablefrom advanced engines.

The use of hydraulic powerfor various utility functions inthe Chinook is without precedentin Army aircraft. Once the decision was made to employ hydraulic starting for the engines(for the reasons previously de scribed), it became evident thatthe employment of hydraulicpower for other functions involved minimum weight andmaximum efficiency. For thisreason, the utility hydraulic system is also used to power therear loading ramp, the externalcargo hook, the wheel brakes,the rotor brake, the centeringlock on the swiveling rearwheels, and the utility winch.

The utility winch, located atthe forward end of the pay oad


10/52

AUGUST 1962

compartment, can be used to pullcargo or vehicles into the aircraft, to restrain wheeled itemswhile they are being unloadedby gravity (the floor slopes 3downward toward the rear), orfor lowering and hoisting (personnel or loads weighing up to600 pounds) through the floorhatchway. The hoist is providedwith 150 feet of cable, a levelwind, and a two-speed gear shift.When operating in the slowspeed position, speed is variableup to 2 feet per minute, and3,000 pounds of cable tension isdeveloped without multiple pulley sheaves. In the high-speedposition, cable speed is variableup to 100 feet per minute, withup to 600 pounds of cable tension. Single-sheave pulley blocksare provided for attachment tofloor tie-down rings so that thelateral location of the cable canbe selected for rear ramp loading operations, or for attachmentto overhead fittings when usingthe winch for hoisting or lowering through the hatchway.

Kits are programmed to takefull advantage of the Chinook sversatility in performing a variety of missions, and to facilitateoperations under various conditions, without incurring unnecessary weight penalties for permanent installation of items notrequired on all aircraft at -alltimes. These include:

winterization kit, ski kit, liquid cargo and extended

range kit, li ter kit, air-to-ground towing kit, bullet-sealing fuel cell kit, armament kit for suppres

sive fire, kneeling kit for rear land

ing gear, static electricity discharge.The fuselage of the Chinook

can be sealed during manufac-

8

ture to provide an inherentflotation capability, permittingoperation from water.

The liquid cargo kit will bedesigned to permit the Chinookto transport liquids efficiently, or- when filled with fuel - toextend the range of the helicopter by augmenting the 630gallons fuel capacity of the integral tanks.

The external cargo hook is designed so it can be used for thetowing of surface items wheninstalled in a centerline positionjust forward of the ramp hingeline on the underside of thefuselage. The towing kit will in clude the fittings for attachmentof the external cargo hook inthis location and extensions forhydraulic, electrical, and manualrelease lines from the hatchwayto the towing position.

The rear landing gear kneeling kit permits reducing theoverall height of the helicopte "from its normal 18 feet, 7 inchesto less than 17 feet, to permitstorage on the hangar deck ofThetis Bay class carriers.

The winterization kit includesthermal insulating blanket toreduce heat losses and enablethe heating system to maintaina cabin and cockpit temperatureof at least plus 40 F when theoutside temperature is minus65 F.

The bullet-sealing fuel cell kitis designed to provide protectionto the lower portion of each tankagainst 7.62mm projectiles.

PROGR M B CKGROUNDThe Chinook program was ini

tiated in the summer of 1958when the U. S. Army requestedthe U. S. Air Force to conducta source selection evaluation fora new medium transport helicopter. Five companies submitted management proposals, andin September 1958, the jointArmy/ Air Force evaluation

team recommended to the U. S.Army that Vertol be selected todevelop this aircraft.

The initial FY 59/ 6 contractincluded ten test and evaluationaircraft plus one static test article. In FY 1961, a second contract, which included 18 additional aircraft was negotiated,and a contract for 24 more aircraft was negotiated in FY 1962,bringing the total number ofaircraft on order to 52.

DEVELOPMENT ST TUSThe No. 1 HC-1B made its

first hovering flight in September 1961. The 150-hour development bench testing of the transmission and the 50-hour ' tiedown test program were successfully completed in December1961. The static test article wasflown from Philadelphia to Dayton via C-133A Cargomaster inApril 1962. The No. 4 Chinookwas ferried from Philadelphia toEglin AFB in May, and climatichangar testing was started inJune.

The No.8 Chinook is the firstHC-1B to enter the U. S. Armyuser testing and evaluation bythe United States Army AviationBoard at Fort Rucker, Ala. No.10 will also be used in thesetests, and will be delivered assoon as the USAF completes thepreliminary pilot evaluation ofthe HC-1B early this fall. Atthat time No.9 will be deliveredto the U. S. Army Transportation Aviation Test and SupportActivity at Fort Rucker forlogistical test and evaluation.

In early 1963, the first 28Chinooks will have been completed and delivered to operatingunits. The remaining 23 arescheduled to be delivered during February through November 1963.

See back page for compari-son of HC-IB Chinook withH 21 Shawnee.)


11/52

RMY VI TION STORYP RT III

FIXED WING IRCR FTM j S T THOMAS M LANG

T HE QUALITY and capabilities of aircraft in the current Army inventory represent adistinct improvement over thehardware that was available thenow-historic 6th of June 1942.Considerable progress has beenmade in both the aircraft andthe tactics employed in theiruse.

f we are proud of the progress made, we may also considerrecent engineering discoveries

hich might augur a new flight

of birds possessing both appearance and capabilities we cannotnow conceive.In this issue fixed-wing aircraft will be presented. In laterissues the rotary-wing and newexperimental models will be re viewed. Then we will try topeek under the curtain to hazarda few guesses on characteristicsof future aircraft.

In the early 1940s Stinson'sL-1 was first designated an observation and then a liaison

airplane by the Army AirForces. It was cumbersome, re quired extensive maintenance,and was obviously impracticalfor artillery observation. At thattime Army Aviation was envisioned as being solely concernedwith adjusting artillery fire.However, a need developed forthe L-1 in the China-BurmaIndia theatre of operations during Wor d War II. The L-1 hada powerful engine and was ableto evacuate wounded over the

9


12/52

AUGUST 1962

mountains in the CBI.In 1941 the Army Ground

Forces (AGF) evaluated L-2s,L-3s and L-4s for use as the Artillery's aerial observation plane.Taylorcraft's L-2s and Aeronca'sL-3s were small, fabric-coveredaircraft used primariiy by theAGF for training. By October1943, L-2s were being producedfor the Army at the rate of 100per month and L-3s at the rateof 5 per month. Contracts expired in early 1944 and were notrenewed. Relatively few L-2sand L-3s ever saw overseas service.

Piper's L-4 was the principalcombat airplane used by ArmyAviation throughout World WarII. t was a slightly modified,fabric-covered J-3 Piper Cubwith the addition of more plexiglass for better observation.

The Army's first L-4 was accepted in early September 1941and was given the Army AirForces serial number AC-42-460.t had a six-volt transmitter and

receiver as well as an antennawhich could be reeled out andin. This airplane was shieldedand bonded and had a winddriven generator.

The L-5 Stinson had a morepowerful engine than the L-4and incorporated a litter-carrying capability in the B model. twas superior to the L-4 in manyrespects but, on the other hand,required more space for landingand taking off. Consequently,many AGF commanders opposedadopting it. However, by 1943ground commanders were reqUIrIng the Artillery's lightplanes to perform many missionsin addition to the adjustment ofartillery fire. The L-4 was notable to satisfactorily accomplishsuch missions as medical evacuation, wire laying, and resupply. A need for the L-5 wasthus realized, and it was firstused in combat by the Army

10

Ground Forces after the breakout at Anzio in 1943. t supplemented rather than replacedthe L-4.

Based on combat experience,the AGF decided in 1945 thatthe desirable characteristics ofan air OP plane should include: a built-in mount for FieldArtillery radios; a built-in intercom system; a payload, fuel range, andcruising speed equivalent to theL-5 without reducing its abilityto operate from small landingstrips; maximum all-around visibility, including a reversibleseat for the observer to permitobservation from front and rear; landing and takeoff capabilities comparable to the L-1; maximum armor protectionfor pilot and observer withoutsacrificing characteristics mentioned above.

The AGF set out to obtainsuch an aircraft. In 1945 a competition was held, and six differ-

ent models, including the L-5,were submitted by light aircraftmanufacturers. Against the recommendation of the Director ofAir Training at the ArtillerySchool (who favored the L-5Piper's L-14 was selected. Thislarger, four-place airplane failedto incorporate some featureswhich would have made i t desirable for Field Artillery aerial observation. Only five were obtained.

Following World War II, theAGF made another attempt toobtain a super airplane thatwould include all of the characteristics mentioned above. A design competition was held andBoeing won with its L-15, thefirst aircraft built according tostrictly AGF specifications.

The L-15 failed to satisfy theAGF in field tests and the contract was terminated after only10 were accepted. The AGFprofited by its experience. tlearned that no single airplanecould incorporate all of the con-

The Army s irst L-14


13/52


14/52

AUGUST 962

United States Army AviationBoard, Fort Rucker; and 73081was tested by TATSA, FortRucker. All three of these aircraft participated in a troop testat Fort Benning, Ga., from 16April to 15 June 1961.Caribou 73079 and 73080 werethen reassigned to a specialproject. Caribou number 73081was reassigned to the Airborne,Electronics and Special WarfareBoard, Fort Bragg, N C.

The Army s first T-37s

The first two production models of the Caribou were flownfrom the Downsview, Canada,plant to Fort Rucker early in1961. Pilots were Capts Thomas H. Hurst and Ephraim A.Berry.

Grumman s AO-1 Mohawkwas the result of a design competition for a medium observation aircraft.

family of Army aircraft in February 1959.

On 14 March 1955 the Armyaccepted its first six U-1A Ottersof an order for 90 from de Havilland. They were first used assupply aircraft by the Corps ofEngineers, which was conducting topographic surveys inAlaska and the Caribbean.

This all-metal airplane is designed for rugged wear and simplicity of maintenance. With astandard seating arrangement itaccommodates 9 passengers, orwith wall seats it carries 14.

The T-37 is a Cessna jet aircraft which was never procuredfor general use by the Army.However, three were borrowedfrom the Air Force and used ina special project (Project LONGARM) to determine the feasibility of using higher performanceaircraft in the Army Aviationprogram.

The Army s need for a medium tactical transport has beenpartially filled by de Havilland sAC-l Caribou. The first threeCaribou, numbers 73079, 73080,and 73081 were accepted on .812

October 1959 and delivered onthe 17th. Number 73079 wassent to Edwards AFB, Calif., forengineering evaluation; 73080was given user tests by the

On 16 September 1960 twoAO-1A Mohawks (numbers92612 and 92616) were delivered

Shown above are the first three Caribous to be delivered to the U. S.Army during a demonstration that preceded the acceptance ceremony on 8 October 1959 at the de Havilland plant.

Shown below are the first 5 Mohawks, 3 YAO models flanked by2 AO-1AF modeLs at Bethpage, N. Y., in July 1960. Production onthe Mohawk, the Army s heaviest fixed-wing aircraft 9,028 poundsempty weight for AO-1AF), began in 1958. The aircraft made itsfirst flight 14 April 1959.


15/52

THE RMY VI TION STORY

to the U. S. Army AviationBoard, Fort Rucker, for usertests. Mohawk 92612 was flownby Maj Albert Drane and Mr.Joe Givens; Mohawk 92616 wasflown by Maj June Stebbins andCapt Al Smith. On completionof the testing, they were transferred to the U. S. Army Aviation School, Fort Rucker, wherethey are still used in training.

The AO-IB differs from theAO-IA in that it is equippedwith side-looking airborne radar

SLAR). The first of these wasdelivered to the Army on 16April 1961. The AO-IC isequipped with infrared mappingequipment instead of SLAR. Thefirst C model was obtained inOctober 1961.

An L-4 converted to serve as an ambulance. In June 1943at Fort Sill, Okla., Maj Victor E. Frazier installed a trap-door and litter behind the pilot s seat. This was the onlyone so modified and the advent of the L-SB obviated theneed. At Bougainville L-4s were similarly modified duringWorld War and later used extensively in the Philippines.

Fixed Wing ircraftL-l Vigilant-Vultee-Stinson two-place pilot and observer).

= Observation, reconnaissance, and medical evacuation. Models rang-. ~ :::::: was formerly designated 0-49. All models were powered by a 295

ing through F were obtained by the Army Air Forces. This aircraft__ .. hp Lycoming engine R-680-9).

Total Obtained1421823

FY First Obtained194219421942

Notes

Ambulance aircraft.

ModelL.:1L-1AL-1BL-1CL-1DL-1EL-1F

121

19431943 L-1A converted for use as ambulance aircraft with one litter.L-1A converted for familiarization in glider training.2 1943 L-1 converted for use as amphibious ambulance.1943 L-1A converted for use as amphibious ambulance.

L-2 Grasshopper-Taylorcraft, two-place pilot and observer).Observation and reconnaissance. Models range through M excluding I). The Army Ground Forces and Air Forces both usedthe L-2. This aircraft was formerly designated 0-57. All modelshad a 65 hp engine except the L, which was 50 hp.

NotesodeLL-2L-2A

Total Obtained74476

FY First Obtained19421942 Tandem seating; Continental engine 0-170-3).Tandem seating; Continental engine 0-170-3).

13


16/52

AUGUST 1962

L-2BL-2CL-2DL-2EL-2FL-2GL-2HL-2JL-2KL-2LL-2M

4901

900

19431942194219421942194219421942194219421943

Tandem seating; Continental engine 0-170-3).Tandem seating; commercially designated DC-65; Continentalengine A-65-8).Tandem seating; commercially designated DL-65; Lycomingengine 0-145-B2).Tandem seating; commercially designated DF-65; Franklinengine 4AC-150).Side-by-side seating; commercially designated BL-65, formerlyUC-95; Lycoming engine 0-145-Bl).Tandem seating; commercially designated BFT-65; Franklinengine (4AC-150).Side-by-side seating; commercially designated BC-12-65; Continental engine A-65-7).Side-by-side seating; commercially designated BL-12-65; Lycoming engine 0-145-Bl).Side-by-side seating; commercially designated BF-12-65; Franklin engine 4AC-150).Side-by-side seating; commercially designated BF-50; Franklinengine 4AC-150).Tandem seating; Continental engine 0-170-3). Modified L-2Awith the addition of spin strips.

L-3 Grasshopper-Aeronca two-place (pilot and observer). Ob-= s __ ~_ JI servation and reconnaissance. Military version of commercialAeronca Challenger. Models range through J (excluding I). TheArmy Ground Forces and Army Air Forces both used the L-3. This

aircraft was formerly designated 0-58. All engines were 65 hp.

ModelL-3L-3A

Total Obtained54

FY irst Obtained1942

NotesTandem seating; Continental engine 0-170-3).

L-3BL-3CL-3DL-3EL-3FL-3GL-3HL-3J

20875490

1010

2

2

194219421943194219421942194219421942

Tandem seating; Continental engine 0-170-3); fuselage 4inches wider than L-3.Tandem seating; Continental engine 0-170-3).Same as L-3B except that radio equipment was omitted; Continental engine 0-170-3).Tandem seating; commercially designated 65-TF; Franklinengine (4AC-176).Tandem seating; commercially designated 65-TC; Continentalengine A-65-8).Side-by-side seating; commercially designated 65-CA; Continental engine A-65-8).Side-by-side seating; commercially designated 65-LB; Lycoming engine 0-145-Bl).Tandem seating; commercially designated 65-TL; Lycomingengine 0-145-Bl).Tandem seating; commercially designated 65-TC; Continentalengine A-65-7).

ttention u s c GradsThe Director of Army Avia

tion is establishing an IBM cardfile for graduates of the ArmyAviation Safety Course at theUniversity of Southern Califor-

4

nia. The file will be maintainedby the U. S. Army Board forAviation Accident Research,Fort Rucker. Help keep it up todate and accurate by forwarding

each change of address and dutyassignment to:

DirectorUSABAARAttn: Data Processing SectionFort Rucker, Alabama


17/52


18/52

AUGUST 962

Total Obtained NotesodelXL-6

Y irst Obtained1942 Commercially designated S-IB Cadet; 100 hp Franklin engine (XO-200-5).L-6 250 1943 Commerc ially designated S-IB Cadet; 102 hp Franklinengine 0-200-5).

L-7A-Universal. These weretwo-place aircraft. Nineteenwere obtained in FY 1943 andsent to France. Each used a 9hp Franklin engine 0-200-1).

Drawings of these six aircraftunavailable.

L-8A-Interstate. These weretwo-place aircraft commerciallydesignated S-lA Cadet. Eightwere obtained for Bolivia. Eachused a 65 hp Continental engine0-170-3) .

L-9-Stinson. These were threeplace aircraft. Eight L-9As and12 L-9Bs were purchased forthe British Navy in FY 1942. TheL-9A was commercially designated the AT-19-A Voyager, andthe B model was designated10-A. Both models used a 9 hpFranklin engine. The A model sengine was 0-200-1 and the B s4AC-199-E3.L-10-Ryan. This was a threeplace aircraft commercially designated SCW 1937). One wasleased by the military for a special project in FY 1942. t hada 145 hp Warner engine 50-499) .

L-11-Bellanca. This was asix-place aircraft commerciallydesignated 31-50. One was leasedby the military in FY 1942. thad a 600 hp Pratt and Whitneyengine R-1340-41).L-12-Stinson. These were fourplace aircraft.

Two L-12s and two L-12Aswere obtained in FY 1944 by theArmy Air Forces for use astrainers. The L-12 was commercially designated SR-5A and theA model, SM-7B. The L-12 useda 300 hp Lycoming engineR-680-9) and the A model a 300hp Pratt and Whitney engineR-985-A) .

L-13-Consolidated-Vultee, three-place (pilot and two litters ortwo passengers) .

The Army Ground Forces tested two of these aircraft in 1945but did not accept them then. Later they were obtained by theAGF; the most ever carried on the Army Aviation inventory were43 in June 1951. Each was equipped with a 245 hp Franklin engineXO-425-5) .

L-14-Piper, four-place pilot, observer and two passengers).Utility. The Army Ground Forces obtained five of these aircraftin FY 1945-6. Each had a 130 hp Lycoming engine 0-290-3).

= =;;;;;;;;;;;;;;;;;;;___ _ - - ' ~ ~ L-15 S c o u t ~ B o e i n g two-place (pilot and observer). Observation

~~ _ . and reconnaissance.r ~ The Army obtained 10 of these tandem-seated aircraft in 1949 for~ JJ service tests only. Eventually they were transferred to the Alaskan

Forestry Service. Each had a 125 hp Lycoming engine 0-290-7).L-l6-Aeronca, two-place (pilot and observer). Observation andreconnaissance.

The L-16A was first obtained by the Army in FY 1947 and the Bin FY 1948. The most L-16As ever carried on the Army Aviation ~ ~ ~ i j J ~ ~ ~ 5 f 7 r inventory were 742 on 30 June 1949. The most B models were ~ ~ ; o ; w ~ - - _ T ' O

Date post:	03-Jun-2018
Category:	Documents
Upload:	aviationspace-history-library
View:	220 times
Download:	0 times

Army Aviation Digest - Aug 1962

Documents