Army Aviation Digest - Oct 1958

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U. S. ARMY A YIATION SCHOOL

:\faj Gen Bogardus S. CairnsCommandant

Col John J. TolsonAssistant Commandant

SCHOOL STAF F

EDITORIAL STAFF

Col 'Villiam H. ByrneFlight S/O'geon

Col \Villiam R. TurkDirector of lnstl ltction

Col Jay D. VanderpoolCombat De'uelopment Office

Col Edward N. DahlstromS e c ~ e t a r yLt Col James L. Townsend

CO US VNS Regiment

Capt Theodore E. 'Vasko

William E. VanreDEPARTMENTS

Fred M MontgomE:ry Col Hobert H. SchulzMaintenance

Col Russell E. \VhetstoneTactics

Lt Col Raymond E. JohnsonRotary Wing

Lt Col Howard 1 LukensFixed ll ing

Lt Col Thomas J. SabistonPublications andNon-Resident Instruction

The U. S ARMY AVIATION DIGE:::;T iq an official publication of the D<,partment of theArmy publish( () mor thly under the super\ binn of the Commandant U. S Army AviationSchool.

Thc mi'ssion of the U. S. ARMY AVIATIONDIGEST is to provid< information of an operational or functional natul'e concerning safety andlIircrnft accident prcvcntion, training, maintenanc(', c'Jlerntions, rescarch and developmE: nt, aviation medicin< , and othcr related data.

Manuscripts, photosrraphs, and other iIIustrntionspcrt.'lin;ng to the above subjects of interest to personFJd concerned With Army Aviation are invited.Direct communication is authorized to: Editor-in

(,hiE-f, U. S. ARMY AVIATION DIGEST, U. S.Army Aviation School, Fort Rucker, Alabama.

Unless otherwise indicated, material in the {T. S.ARMY AVIATION DIGEST may be reprint('d providC d credit is given to the U. S. AR"dY AVIATION DTGE::iT and to the author.

Thc printing of this publication has been approved by the Director of the Bur('au of theBudgct, 15 Ma"ch 1956.

Pnless spe< ified all photographs used arc U. S.Army.

DISTRIDt'TroN:Active Army:OSD, JCS, OSA, ('ofS, DCSPER,

ACSI, DCSOPS, DC SLOG, CINFO,CNGB, (TRARIWTC. (,RD, eMH,Technical DA, MP Rd. USA ArtyBd, t 'SA Armor Rd, t ~ A Inf Bd. USAAir d Ed. U::iA AI n Ek t RdUSCONARC, US ARADCOM. OS ?lnjComd MDW, Armies. ('orp.,. Div. n,.jg,S<,p Avn Co, Ft Camps (CONt'S),

rSMA. SvcC o l I ( t ; c ~ .

NWC , AFSe,ICAF. USAARMS tTSAAMS, USAF-S,USAIS, USARIS, USA Prim Hel Sch.Ord GM Sch. Ol d Sch. rSASCS.U S A T S C H T A G S U S A U S A C H S

rSACMLCSCH. F::il 8A, USAINTS.TJAGSA, AMSS, Fld Comd AFSWP,Trans Sup Maint Comd. MAAG. MilMis. Mil Di<,t.NG: State AG.eSAR: None.

For explanation of abbrcviations used.sec A R 320-50.



UNITED ST TES

RMY VI TION

DIGEST

Volume 4 October 1958

RTICLES

Helicopter-Borne OperationsBrigadier General Carl I. Hutton, USA

Helicopter Maintenance Trouble Shooting .

CWO La.wrence W. Bender TC

Crash Design from Crash Injury Research

Captain William R. Knowles MSC

Helicopters in Survey Operations

Captain Robert P. Litle Jr. In

Pride Kills Local Pilot .

Major Jerome B. Feldt TC

DEP RTMENTS

Notes from the Pentagon .

Master Army Aviator .

Books for the Army Aviator

Memo from Flight Surgeon

Puzzler

Gray Hair Department

Number 9

5

9

2

16

9

8

2

22

24

25

Note: See correction of lost month s cover on page 18 of this issue - The Editor

1



lectronicConfiguration

of the Mohav k AOM

T HIS ARTICLE INITIATES a new policy under this title of pro-viding timely information to aviators in the field on recent

briefings and major actions which take place in the Pentagon.In a recent briefing Captain George Rizor of OCSigO, R D,

presented the following information O n the electronic equip-ment which will be installed in the Mohawk AOM, the im-

proved observation airplane developed by Grumman.

The production models of theMohawk will be quite differentfrom the prototype scheduled t

begin engineering tests in early1959. The Y models will contain standard navigation and

communication systems, givingthem a capability for visual ob

servation, day/ night photography, and other miscellaneousArmy Aviation missions. Allproduction aircraft will containadditional communication equipment, self-contained navigationand integrated flight instrumen-tation systems. The A modelwill also contain Infrared IR)equipment capable of strip map

ping terrain and pinpointingconcealed objects both day and

night. The B model will contain Side Looking i r b 0 r n eRadar SLAR) equipment capable of strip mapping the terrainand pinpointing objects on thesurface under any visibility conditions.

Many i t e m.s of electronicequipment are required to fulfillthe various functional requirements of these complex airbornesurveillance systems. The functions required and the bestavailable equipment compatiblewith proposed production air-craft delivery schedules) chosenfor use in the A and B

model Mohawk aircraft are asfollows:

2

FUNCTIONCOMMUNICATION

UHF

FM

HF

InterphoneNAVIGATION

Heading Reference

ADF

TACAN

Marker Beacon

FM Homer

Self-containedNavigation System

ELECTRONICS EQUIPMENT

Radio Set, AN I ARC-51Radio Set, AN I ARC-44 with AN I ARR-46 in B

model)High Frequency Radio Set, AN I ARC-39Interphone Control, AIC-12

Gyro Magnetic Compass System (lear MA-1 )furnished as a component of the self-containednavigation system

Direction Finder Set, ANI ARN-59Radio Set, AN I ARN-21Marker Beacon Receiver with 3-light adapter,

R-737/ ARNAntenna Group, AN I ARA , modification of the

AN / ARA-31)Automatic Doppler) Navigation and Flight Control

System, Ryan Model 120A



NOTES FROM THE PENTAGON

Integrated FlightSystem

Integrated instrument furnished as a component of

the self-contained navigation system

Absolute Altimeter

Autopilot

Radar Set (Radar Altimeter), ANIAPN-22

Universal Autopilot, ANI ASN ( ), (under develop

ment at Sperry Gyroscope)

IDENTIFICATION

IFF Transponder Set, ANIAPX-44Ground Tracking Beacon Transponder Set, ANI APW- ( ), (the airborne por

tion of the AN/uPW-l under development at

Ford Instrument Company)

SURVEILLANCE SYSTEMS

Photo Aerial Camera System, KA-30 (alternate capability

only, in Bt model)

Camera ControlIR ( A model only)

SLAR ( B model only)

Joint Army-Navy Camera Control System (JANCCS)Infrared Surveillance System, AN / UAS-4 (XE-l)

Radar Reconnaissance System, ANIAPS-94

The UHF communication andTACAN navigation radio setshave been included in the Aand B models of the Mohawkfor use in the forthcoming common Traffic Control and Navigation System within the continental United States. In addition these items will be requiredfor operations in conjunctionwith the Air Force and Navy inmany future tactical situations.Provision will be made to allowremoval of both these i tern swhen they are not required. TheUHF, AN/ARC-51, presentlyunder development at CollinsRadio Company will furnish theMohawk with 18 preset channels (1750 available), plus asingle guard channel in a small35 lb., 6/10 cu. ft. package. TheAN/ ARN-21 is the pr s n tNavy standard TACAN.

The FM Radio Set, AN ARC-44, is the standard tactical radioin most Army aircraft today and

will be usedas

such inthe

Mohawk. The B model willcontain an AN ARR-46 RadioReceiving Set for use as a singlechannel monitoring receiver.

The High Frequency RadioSet, AN ARC-39, is required forlong range and non-line-of-sightcommunications. This 12 preset

channel set weighs 40 poundsand is capable of more than 10watts output. The interphonesystem through which all thecommunications and navigationequipment operates is a small2 ~ p o u n d system, and is compatible with the headset andmicrophone in the new ArmyAviator Protective Helmet (NavyType APH-5 modified).

The standard AN ARN-59ADF is required for operation inthe present Army Aviation AirTraffic Tactical Operations System. The Marker Beacon Receiver, R-737/ARN, is not onlyrequired for tactical Army usebut in the common system ofair traffic control as well. TheFM Homer Antenna G r 0 u pAN ARA - ( ), is required asan emergency navigation assist.For its additional 4 pounds, thisunit will give the Mohawk pilotthe capability of homing on anyFM ground radio within thefrequency range of the AN ARC-44.

The Self-Contained AutomaticDoppler Navigation and FlightControl System is required notonly by the pilot for tacticalmission navigation, but also bythe Infrared and Radar Surveillance Systems. This information

3



Helicopter-Borne Operations

Brigadier General arl I. Hutton US

OBSERVATION OF SOME recenthelicopter -borne exercises

pointed out the necessity for emphasis upon some basic principles in that type of operation.There is nothing new about the

principles. They make sound tactical sense and when they areignored they not only endangerthe success of the operation, butthey also create an impressionof excessive vulnerability in observers minds. Despite explanations that certain practices arefollowed for reasons of peacetime safety, a mental image of

a profitable target is likely to remain.

The helicopter borne operationshould preferably be made ontoan UNOCCUPIED 0 B J ETIVE. Helicopters are especially vulnerable to enemy fire during the short period when theyare on the ground dischargingtroops. On today s thinly occu

pied battlefield, it should not bedifficult to find objectives for thehelicopter-borne elements whichput the forces behind or uponthe flanks of the enemy force. Ifthe objective is occupied, supporting fires must be lifted priorto the landing, with the likelihood that the enemy will havetime to come out of shelters and

man his weapons during themost vulnerable period. Whenthe landing area is on the flankor behind the objective, the supporting fires can be maintainedduring the landing phase.

Some particular condition mayfavor making an exception to

this principle. Glider landingsare supposed to have been madeupon Fort Ebn Emael in safetybecause the fort was not designed to resist an attack fromthe air. If the objective for

the helicopter-borne operationshould be similarly vulnerable,the action may well be plannedto land directly upon it.

T he helicopter borne o r c eshould e delivered with SURPRISE . The achievement of surprise is possible either in theselection of the point of actionor in timing, or both. The entire

width and depth of the battlefield are exposed to the helicopter-borne operation. Static defense by weapons in position willrequire that the enemy try todefend everywhere, resulting indispersal of his weapons. A 100percent defense everywhere willresult in a 99 percent waste ofeffort, since it will be effective

only at the exact point of attack.Areas of difficult t r r a in,which are difficult obstacles fortroops on the ground and theirvehicles, favor achievement ofsurprise in space. Smoke may be· Near Liege, Belgium, 1940.

Brigadier General Carl I. Huttongraduated from USMA in 1930. Hejoined the Army Aviation program in1946 and was Director of the Depart

ment of Air Training at Fort Sill. Hewas Commandant of the Army Aviation School from 1954 to 1957 priorto his present assignment as the Com-manding General of the 8th InfantryDivision Artillery. Views expressedin this article are the author s and arenot necessarily those of the Department of the Army or of the U. S.Army Aviation School.-The Editor



OCTOBER 1958

used in some cases to blindenemy observation but wit hpresent instrument equipment inhelicopters smoke may hinderlow-level flight if it is used improperly. The basic principle ofsmoke operations should be keptin mind: t is much more effective when put upon theenemy's position to interferewith his observation than whenit is put in front of our own

position to conceal our movement.Secrecy always contributes to

surprise. Rehearsals should nottelegraph the operation. Re

connaissance and photographicactivities necessary in prepara-tion for the action should beconducted on wide frontages orin conjunction with activities

which do not disclose theplanned operation. Communication discipline must be stressedbecause of the number of peopleinvolved in planning the operation and the amount of radioequipment which is at hand.Panel markings of pickup andrendezvous zones are easily detected from the air and from ob

servation posts. Careful planning and preparation shouldmake them unnecessary.

CHIEVING SURPRISE

Surprise in timing should besought by varying the time andmethod of attack. While dark-ness and early morning and lateevening twilight favor the heli

copter-borne forces surprise islessened if the attack is repeat-edly conducted at those times.Surprise in timing can also beachieved during the shock periodafter a tactical atomic strike,under cover of jet aircraft noiseor perhaps in conjunction with

6

a chemical attack. Low visibility which restricts or preventsthe operatio.n of conventionalaircraft favors the helicopterborne movement. Transito.ry co n-

ditions such as thunderstormsand snow storms will offer concealment but their exploitationwould require a great deal offlexibility in planning and execution.

SPEE COUNTS

T he helicopter borne actionshould e delivered wit SPEED.Speed is the very essence because the easily attainable crossco.untry speeds are unique tof ly ing machines. Speed isachieved by preparatio.n ndplanning. Simplicity in execution should be so.ught in the in

terest o f speed. Each pilot shouldbe assigned an exact place in theflight formation determined bythe location of his point of landing in the objective area. Columnar formations are avoided because they prolong exposuretime.

After the operation is underway the helicopters should no t

be at rest more than a fewmoments. The pickup p 0 i n tshould be cleared as rapidlyas the landing area. After thepickup the helicopter should godirectly to a reorganization areawhich should be at least fivemiles away from the pickuppoint preferably in the vicinityof the last defilade on the way to

the objective area. Each helicopter's po.sition within the flightformatio.n should be the same asits touchdown position in thearea. Aerial pho.tographs sho.uldbe marked to show the exactpoint where each squad is to debark. Only helico.pter-borne ac-



tions can land troops upon theobjective in preplanned combat

formation. This advantage cannot be overemphasized.The route is reconnoitered in

flight, by map, and by aerialphotography. If there is time, aphotographic strip mosaic shouldbe prepared and marked, showing the precise route from terrain feature to terrain feature.This strip should show flight

hazards and obstacles and safeabsolute altitudes required toclear them. The lower the flightaltitude in any terrain, the fewerenemy guns can be brought uponthe flight. n some corridors ofterrain low altitude will protectthe flight from fire outside thecorridor. This low-altitude feature is especially important be

cause it limits the requirementfor supporting fire.

UT GROUN TIME

The period on the groundwithin the objective area shouldbe less than one minute. A halfminute should provide an easytraining goal. Additional heavylifts after the initial lift shouldbe handled with the same consideration for the principle ofspeed. These flights are as vulnerable to enemy fire as theinitial flights.

If speed to the degree indicated as possible by the foregoing is achieved, there is littlechance that enemy fire otherthan direct fire weapons can bebrought onto the objective areaduring the course of the operation. The troops on the groundgain their protection from retaliatory fires by immediate dispersal to their preselected positions.

The speed of the operation de-

HELICOPTER-BORNE OPERATIONS

scribed is far greater than thespeed possible with surface ve

hicles. Combined with the landing of troops in combat formation, this speed makes the helicopter-borne action one of themajor tactical advances of thelast 50 years.

FIRE SUPPORT

The helicopter borne o r c eshould e SUPPORTED BY

FIRE. The helicopter action isa combined arms operation. Allmethods of support should beused. Artillery should not onlyplan flak suppressive fires, butknown enemy positions shouldbe neutralized by successive concentrations during the progressof the movement. Tactical airsupport is especially important

for dealing with targets of opportunity which appear duringthe operation. The action, oncestarted, will be so rapid thatthere will be insufficient time tomake corrections in the artilleryfire support plan. Tactical aircraft, guided by a controIlerwith the helicopter force, engage targets which were not located and anticipated in the fireplan. Protection from hostile aircraft should also be providedduring the short period of theaction. This is not air coverwhich must be maintained forhours, but a momentary periodof air superiority over the objective area.

he helicopters themselvesshould have a suppressive firecapability to be used as a deterrent to accurate hostile fire. Machineguns on each helicopter inthe formation are used to keepsome fire faIling in the immediate area through which the helicopters are passing. If the ob-

7



OCTOBER 1968

jective is occupied by the enemysuppressive fire will minimize

losses.Atomic strikes, chemicals and

long-range rockets are othermeans of fire support which maybe used when appropriate.

These are familiar tacticalprinciples. They involve nothingrevolutionary. Some degree ofsurprise is or should be soughtin every tactical

operation.Fire

support is coordinated whenever possible. The planning ofan attack to make the final action from a flank or from therear is tactically sound. The emphasis is new only in the sense

that the speeds now attainableare new. When the soldier could

move across country at about2 miles per hour there waslittle point in planning operations at 50 or 100 mph. Surprise,speed firepower and hit themwhere they ain't all make goodtactical sense. The employmentof combined arms is the secretof success here as in other operations.

The problem of meeting theseattacks is very interesting, as aseparate subject. It seems likelythat perhaps a new form of warfare is developing in whichgreater tactical speeds will beused than ever before.

Airborne attack information along the lines covered in this article can befound in FM 57-35 prepared by the Infantry School in close coordination withthe Army Aviation School. This manual is now being printed and will be distributed shortly. The material is presently available in Training Text 57-35-2.The Editor.

M STER RMY VI TOR

CAPTAIN HARRY W. WILTSE JR. is the first ArmyAviator in the Fourth U. S. Army to be awarded theMaster Ar my Aviator rating. His present assignmentis chief of the Flight Operations Branch, AviationSection Headquarters, Fourth U. S. Army, Fort SamHouston, Texas.

He began his Army flying career upon graduation.......... in 1943 from Liaison Pilot Class No. 23 at the U. S. A.

Artillery School and as a Liaison Pilot with the 28thInfantry Division. After World War II, he served as

flight instructor and flight commander at the Air Training Depa.rtment FortSill. He was a helicopter pilot with the 4th Helicopter Detachment in Korea.

Subsequent tours as an Army Aviator were with Headquarters, Fifth U. S.Army; Headquarters, Seventh Army, USAREUR; and Headquarters, USAREUR Flight Detachment. Between assignments he completed the Associate BasicCourse at the Artillery School the Instrument Training Course at theSpartan School of Aeronautics, and the Instrument Flight Examiners Courseat the U. S. Army Aviation School.

Captain Wiltse is instrument qualified dual rated, and has logged over5 576 hours. He has been rated an Army Aviator for more than 15 years andp r t i c i p t ~ d in campaigns in World War II and the Korean conflict. He wearsnine Oak Leaf Clusters to the Air Medal.

8



Helicopter Maintenance Trouble

Shooting

WO Lawrence W • Bender T

U CH OF THE TROUBLE en-countered in the routine op

eration of helicopter components, such as the engine, landinggear, radio, and instruments, issimilar to that in conventional

type aircraft and presents nonew problem to pilot or mainte-nance personnel. There are someaspects of helicopter troubleshooting, however, related to vibrations and control stick forces,whose underlying causes aremore difficult to detect and correct. Pilot and maintenance per-sonnel should become familiar

with these vibrations and theireffect on helicopters.

All flight personnel must real-ize that unusual vibrations orstick forces are not normal conditions inherent in the helicopter. They should be treated withas much concern as a malfunc-tioning engine. Certain informa-tion to follow can help person

nel understand the probablecauses of some unusual conditions and guide them in makingcorrections.

While all helicopters are subject to certain normal vibra-tions, there are others which canbe recognized as abnormal vibrations. The vibrations andstick forces discussed here are

peculiar to the Chickasaw, Choctaw, and Mojave single rotort y p e helicopters. Vibrationshave been divided into threegeneral groups: 1) low frequen-cy, 2) medium frequency, 3)

h i g h frequency. Experiencedpersonnel can distinguish these

various frequencies of vibrationby clues which become almostsecond nature to them.

LOW FREQUENCY VIBRATIONS

The low frequency vibration,

found in the main rotor, is feltas a strong shake or beat at arelatively slow rate. If the fuselage transmits the vibration, thebody of the pilot or passenger isnoticeably shaken and bouncedat a strong, slow rate of approximately three, six, or nine timesper second. If the control sticktransmits the vibration, the pilot

feels a constant repeated kickin the stick at the same frequen-cy. In some cases the vibrationwill be felt in both the fuselage and the stick. If a vibrationreaches the pilot through servocontrols it will be of great mag-nitude. The stronger the vibra-tion force, the more urgent isthe need to find the cause.

If vibration is noticed pre-dominantly through cyclic, theprobable cause is that the bladesare out of track for one or moreof the following reasons:

a. Blade damage.

CWO Lawrence W. Bender is an instructor in the Choctaw Departmentof Rotary Wing Training, U. S. ArmyAviation School Fort Rucker, Ala

bama. A former Marine Corps aviator Mr. Bender instructed duringWorld War II and flew Corsairs inthe Korean conflict. He has over 4 000total hours in rotary and fixed wingaircraft. Views expressed in this article are the author s and are notnecessarily those of the Departmentof the Army or of the U. S. ArmyAviation School.-The Editor

9



OCTOBER 1958

b. Improper tracking adjustment.

c Malfunctioning dampersdue to: leakage dirty fluid, lossof fluid, air in system improperrelief valve operation or bindingin attachments giving a false

damper rate.d. Malfunctioning sleeve or

horn assembly.Vibration noticed predom

inantly through the fuselage

comes down through the mainrotor shaft; consequently thefaster the speed of rotation thegreater the vibration. Its causesare:

a. Worn flapping hinge bear

ings .b. Faulty drag hinge bear-

ings.

c Hub improperly installed.

d. Structural defects.e. Gear box improperly installed.

f. Pylon support legs not

torqued.g. Excessive play in t h e

rotor shaft.h. Loose hub base nut.

ME IUM FREQUEN Y

The tail rotor drive shaftingand the intermediate and tailrotor gear boxes can cause bothhigh and medium frequency vibrations. Medium frequency vibrations are always confined tothe tail rotor and will be felt asa localized vibration originatingin the tail cone. If in doubt increase the tail rotor cable ten

sion. In the H-19, the cableswill transmit the vibrations tothe pedals where they can berecognized by the pilot. To determine vibrations in the H-34and the H-37, the tail rotor servo

would have to be disconnected.Medium frequency vibration

10

can be traced to the followingcauses:

a. Rotor out of balance.b. Rotor improperly rigged.

c. Blade damage.

d. M alfunctioning s l ee v ebearings.

e. Malfunctioning trunnionbearings.

f. E xcessive rod-end play.g. Worn rod-end bearings.

h. Structural or mountingdefects.

HI H FREQUEN Y

The high frequency vibrationoccurs at engine speed or athigher multiples of engine speed.It cannot be clearly felt, but itis noticed by personnel as atingling sensation in the soles ofthe feet or a tickling sensation

in the nose. The instruments arevibrating at such high speedthat the indicators cannot beclearly seen and appear fuzzy.

High frequency vibration isfound in the transmission clutch

fan or engine. An auto rotationshould be made to localize thesource. Some of the causes are:

a. Faulty vibration insula-

tors.b. Damaged engine mount.

c. Damaged fan blades.d. Improperly balanced driv

ing disc.e. Improper s s e m b I y of

clutch.f. Damaged spline coupling.g. Damaged drive shaft.h. Faulty tail rotor d ri ve

shaft bearings.i Damage to tail cone.j. Damage to tail drive shaft

support bracket.k. Loose tail cone.1 Malfunction of any gear

box.m. Pylon improperly secured.



HELICOPTER TROUBLE SHOOTING

STICK FORCES

Excessive play or binding in

the controls can be corrected bythe standard method of disconnecting and isolating the varioussections of the linkage until thefaulty parts are found. Theremay be times when the controlsystem operates smoothly on theground but becomes excessivelystiff when flight loads are imposed. Under such circumstances

the trouble is generally found inthat part of the linkage whichincludes the servos, and betweenthe servos and the blades.

Lateral stick force, induced bythe main rotor, is usually to theleft; however, in the H-19, withthe servos off, the stick willmove to the right. While minorat low speed, it increases with

speed.1 Stiffness is probably causedby:

a. Binding of self-aligningbearings.

b. Control linkage bolted

too tightly.

2. Looseness is p ro b a b 1 ycaused by:a. Azimuth stick loose in

the socket.b. Worn bearings.c Ball and socket as

sembly too loose or worn.3. La eral o r c e s can be

caused by:a. Sloppy joints.

b. Servo links tight.c Servo piston leak.

4. Sharp fore and aft kickcan be caused by:

a. Blade stall.b. Longitudinal s l op p y

joints or servo links.c Damper out of time,

low on fluid or leaking.

These are only general causes

of vibrations and stick forceswhich can be encountered in thehelicopter. There are many otherunlisted causes which experiencealone can help you locate.

A leHer from Capt Theo C Watkins, Maintenance Officer, AIM, Ft Benning, Ga.,

suggests more information be disseminated concerning our June-July 1958 Puzzler.

in actual operation of the counterweight prop where engine oil pressure

stepped up through the governor moves the blades to low pitch (high rpm) andcentrifugal force and the counterweights carry the blades to high pitch (low rpm),

the propeller will continue to maintain the cockpit rpm setting during failure until

all the engine oil supply is exhausted. Corrective action in the event of prop trouble,

whether it be a blown seal or otherwise, is to go into full high pitch (low rpm).

Probably the first indication of prop trouble on the Beaver will be a heavy film of

oil thrown on the windshield or a fluctuating rpm. Thank you, Captain Watkins.The Editor

1J



Crash Design from Crash niury

Research

aptain William R Knowles MS

UNTIL RECENTLY the effective-ness of crash protection was

not appreciated because of acommon misconception that thehuman body could not withstand

the sudden deceleration normally associa ed with an aircraftaccident. Even though the cockpit might have remained intactand the occupants held in placeby safety belts, many personsfelt that the abrupt stoppageand associated forces due to impact were causes of fatalities.

Now it has been proved that

no aircraft in operation today isas capable of resisting impactforces as is the human body,provided the body is reasonablysupported. We know also thatthe majority of persons killed inaircraft accidents are so injuredin one of four ways:

(1) Collapse of the fuselagestructure inward upon them.

(2) Their bodies become missiles and are thrown forwardagainst cabin or cockpit structures such as the instrumentpanel, control wheel, etc.

(3) Although restrained by asafety belt, they are flung violently against some structurenear their seat.

(4) An obj ect, such as a fire

Captain Knowles is the U. S Armyrepresentative with the Cornell Uni-versity Crash Injury Research Divi-sion, located at Phoenix, Ariz Viewsexpressed in this article are the au-thor s and are not necessarily those ofthe Department of the Army or ofthe U S Army Aviation School -The Editor

2

extinguisher in the cabin orcockpit breaks free and isthrown violently against them.

Knowledge of the cause of injury or death in aircraft acci

dents has been extremely usefulto modern aircraft designers.Most of them are now workingto build aircraft which will provide crash protection to occupants in all except nonsurvivableaccidents.

Crash protection f e t u res

which increase an occupant schances of surviving are not de

velopments that just cam eabout. For the past 14 years,A via ion Crash Injury Researchof Cornell University (AV-CIR)has been conducting a researchprogram directed toward finding the causes of injury anddeath in survivable aircraft accidents. This research has provided the aircraft industry with

facts and figures which theyhave used in designing morecrashworthy aircraft.

BUG BOOS DE UNKED

Until a few years ago, aircraftwere built solely to fly-not tocrash. This singular approach todesign was costly and is nolonger acceptable to many manu

facturers in the aircraft industry. Manufacturers previouslygave little thought to whethercockpit or cabin design, or theaircraft structure as a whole,was dangerous and capable ofproducing injuries to the occupants. The cockpit and cabin



were designed strictly for utilityand in some instances, for com

fort. No thought was given tothe part design might play inprotecting or endangering occupants in a crash. When a crashdid occur injuries were acceptedas one of the hazards of flying.If a person was lucky he escapedserious injury; if he was unlucky he was killed. Chanceseemed to be the determining

factor. However in analysis ofaccidents from the standpointof injury causation it was observed that a great degree ofboth safety and danger frequently existed in the same accident.

To determine where crashsafety begins and ends a studyof crash injuries in light planeaccidents was undertaken. The

results of the study indicatedthat a direct relationship existsbetween injuries sustained byoccupants and the design of theaircraft structures surroundingthem.

TYPIC L INJURIES T LLIt was further observed that

some inj uries were typical ofcertain types of accidents. Research dispelled the belief thatcertain other inj uries were to beexpected. As an example manythought the snubbing action ofa two-inch safety belt caused internal injuries and would cut aperson in half under severe impact. This belief was so widespread that some people wereactually unfastening their safety belts prior to crashing.

Years of research revealedsome startling facts regardingthe use of safety belts. Amongthousands of survivors of military and civilian accidents lessthan 1 percent showed evidence

CRASH DESIGN RESEARCH

of internal injuries caused bythe snubbing action of the belt.

Considering the large numberof safety belts that have beenbroken and the violence withwhich people are thrown in alldirections in a crash, this factserved to dispel many doubtsabout the use of safety belts. Italso proved there was very littlecorrelation between the belt andinternal injuries sustained in an

accident.Another common misconception concerned shoulder harness.It was thought that a pilot wearing a shoulder harness wouldprobably suffer a broken neck ifinvolved in a fairly severe accident. Many also believed that,with or without harness, theviolent impact of an aircraft ac

cident inevitably snapped an occupant s neck so why wear it?

Again, crash injury researchproved this belief false. Thestudy indicated that, except forextreme (disintegrating type)accidents shoulder harness offers major protection to thechest and head by restrainingthe body in the seat and pre

venting it from smashing againsta control wheel or instrumentpanel. Further evidence indicated that the human neck andchest are capable of withstanding forces of extraordinary violence when properly supported.

OTHER INJURIES

Head injuries normally account for about 75 percent of aI

fatalities in aircraft accidents.Thus, injuries of the head-notthe body-are the determiningfactor as to a fatality or leasserious injury in accidents wherecabin or cockpit structure is notcollapsed and harness is not

13



OCTOBER 1958

his crash told a story to crash iniury investig tors

utilized. t becomes imperative

then that the occupant be ~strained by shoulder harness toprevent his head striking againstsome structure and suffering, inall probability, a serious or fatalinjury.

Research also showed t h t

fractures of the extremities,though fairly common in acci-dents, are usually nonfatal.

Painful, yes, and in some casesperhaps the cause of death dueto incapacitating the occupantand preventing his escaping apostcrash fire.

Spinal fractures, however, arecommon to certain types ofcrashes and certain makes ofaircraft. Most of these inj uriesare compression fractures of thelumbar spine due to the down-ward impact caused by crashingat high speeds and low angles ofattack. In certain aircraft, oncethe gear has washed out theaircraft bottoms hard on thebelly and the occupant receivesthis force vertically through the

14

seatpan and associated struc-

ture.Without a seat designed to

collapse progressively and ab-sorb the impact energy, the oc-cupant receives a force greaterthan his spine can tolerate andhe suffers a dangerous fracture.New ideas in designing gear,fuselage, and seat structure toprevent such injuries are being

incorporated in some of ournewer aircraft.

STUDIES EV LU TED

What conclusions can we makefrom studying crash injuries?One conclusion is t h t thehuman body can tolerate veryheavy forces, much heavier thanthe aircraft can withstand. Weknow that if we restrain occu-pants in their seats and preventtheir heads and bodies fromstriking any part of the aircraft

by means of safety belts andshoulder harness), they shouldsurvive all but extreme disin-tegrating type) accidents.



With knowledge of the mostfrequent injuries, their severity

and causation, Aviation CrashInjury Research provides engineers and designers with factualinformation which they can incorporate into crash protectionfeatures for most aircraft. Toguard against some compressionspinal inj uries, landing gear hasbeen designed to collapse progressively to eat up the en

ergy of the crash. To protect occupants from being crushed insevere accidents, fuselage structure surrounding the cockpit andcabin is being built to withstandgreater impact forces to impedean inward collapse upon the occupant.

IMPROVE ESIGN

Many seats are now delethalized and designed to hold securely in the event of a crash. Astrong seat tie-down preventsthe seat from tearing free at impact and throwing an occupantinto another seatback or forward against cabin or cockpitstructure. Seats are also designed to collapse progressivelyto absorb the force of a crash.The energy-absorbing qualitiesof the collapsing seat structureaid in dampening the force ofimpact and prevent the occupants from bottoming h a r dagainst the seatpan or floorstructure. This, of course, offers further protection to thespine.

Based on data accumulatedfrom hundreds of accidents, engineers are now designing cockpits of some military aircraft towithstand predetermined forcesof 40 Gs or more without collapsing. Instrument panels insome aircraft are engineered to

CRASH DESIGN RESEARCH

fall outward at impact or constructed of a delethalized mate

rial that will yield and absorbenergy, thus preventing head injury if an occupant is pitchedforward against it.

The interior design of manyaircraft is being modified andcleaned up to do away with projections, knobs, handles, etc.,which could cause injury ordeath if struck by an occupant.In other words, new aircraft design is in the process of incorporating delethalization tothe fullest extent possible.

Analysis of data indica edsafety belts and shoulder harness should be designed to withstand greater crash forces. Thisis now being accomplished, andmany shoulder harness typeshave also been modified to include automatic locking devices(inertia reels to snub the occupant in his seat at the instant ofimpact. These and many otherimprovements in crash-survivaldesign are the result of crashinjury research.

Most manufacturers today are

safety-minded and wish to market an aircraft which, if involvedin an accident, will afford all occupants the maximum protection from injuries.

Future aircraft, designed according to the strength andweakness of the human body,will play a tremendous role inreducing injuries and fatalities

in survivable accidents. In time,only those accidents in whichthe aircraft is disintegrated bycrash force will be accepted asnonsurvivable.

WEAR YOUR SHOULDERHARNESS-IT MIGHT SAVEYOUR LIFE.

15



elicopters in Survey

Operations

Captain Robert F Litle, Jr., In

E VERY ARTILLERYMAN KNOWS

the importance of survey.Massed artillery fire can be nomore accurate than the surveypreceding the laying of the

pieces. t is also important thatthis survey be conducted asrapidly as possible; this becomesa more pressing need with modern concepts of warfare.

We must continually seek better and faster means for expediting survey operations. Asearly as World War II the firstattempts were made to utilizethe L-4 aircraft as an aid in sur-vey operations. These early endeavors consisted principally ofusing two or more instrumentsto track a fixed wing aircraft,which flew toward or away fromthe instruments to facilitatetracking until the pilot judgedthat he was over the point to belocated. The pilot then transmit-

ted Mark by radio and theinstrument operators c e a se

tracking to read their instru-ments in the conventional manner. To increase accuracy aspecific portion of the aircraftwas used as a sighting pointsuch as the cross braces of thelanding gear. The time lapse between the initial transmission bythe pilot and the reaction of the

Captain Robert F. Litle, Jr. ispresently assigned to OSACEURFlight Section SHAPE Headquar-ters. Views expressed in this articleare the author s and are not neceS-sarily those of the Department of theArmy or of the U S. Army AviationSchool.-The Editor

6

instrument operators made theresults hardly satisfactory. Accuracy was little better thanthat attained from visual mapinspection. Although somewhat

useful in unmapped or poorlymapped areas and assisting ininitial orientation such a survey was practically worthlessin building a survey firing chart.

SURVEY ID

The advent of the rotary wingaircraft in Army Aviation open

ed new considerations to the surveyor. One of the greatest delaysin survey operations is the timeloss in movement from one instrument station to another particularly in difficult terrain. Iftriangulation is being use dwhere the terrain is difficult orimpassable or covers long distances in each leg one or morehelicopters can materially reduce the time of movement.

Even though only one helicopter is available it can assist bycarrying men and equipmentfrom one station to the next. Atransport helicopter can easilymove a survey party of four tosix men with their equipment.The following illustration demonstrates the time saved by utilizing the helicopter to assist survey operations:

The target area of a field artillery range at one of the serviceschools had never been accurately surveyed to the satisfactionof the senior artillery instructor.



HELICOPTERS IN SURVEY OPERATIONS

One Raven was used to accomplish three-point triangulation

and insure the accuracy of thetarget location. t expeditiouslycompleted a project that threebattalion survey parties had

been working on for some time.Two instrument locations were

established at known controlpoints and a third instrumentoperator was placed in theRaven. All three operators were

in radio contact the operator inthe helicopter using a pack-typeradio. The Raven landed the instrument operator near each ofthe targets, many of which wereinaccessible by vehicle. he

angles read by each instrumentoperator were reported by radioand added together to check accuracy before moving the target

area instrument.In one afternoon of field work

this exercise permitted the instructors to determine which ofsome 50 targets had been accurately located by the battalionsurvey parties. Use of motortransport or movement by footwould have required two or moreweeks to complete the task.

POSITION HE K

Subsequently it became necessary to accurately check thebase angles of some 15 batterypositions. In this case a differenttechnique employing the helicopter was used.

An aiming circle was placedover the battery center and asecond aiming circle was placedon the orienting station of thebattery. The Raven hovered overthe base point in the target areawhile the instrument at the battery center tracked it. t wasnecessary to hover out of groundeffect at altitudes of 500 to 2 000

feet to be visible from the battery position. When the pilot

judged that he was over the basepoint he transmitted Mark byradio. The battery instrumentoperator stopped tracking, referred to the instrument at theorienting station, and announcedthe reading. The instrument operator at the orienting stationset the announced reading, laidon the instrument at the battery

center, referred to the end of theorienting line and read the correct base angle.

Repeating the procedure insured the accuracy of the results. A cargo helicopter thenmoved the two instrument operators to the next battery position where the procedure was repeated.

The survey work was done ata distance of 3 000 - 6 000 yards,and subsequent survey provedthat the results were accuratewithin one mil. Three of the 15base angles previously used werefound to be in error. These corrections enabled the school troopbattalions to register faster andobtain more accurate results,

making it a more effective firingdemonstra ion.

The procedure described canbe used where the target cannotbe observed from the surveybase with creditable results. t

should approach the order of onein 2 000 where the pilot positionsthe helicopter by judgment.

TIME S VER

A comparable task was assigned the Engineer Group atFort Rucker during the fall of1957. This project was to checkthe accuracy of all artillery gunpositions on the Fort Ruckerrange. t would have been im-

17



OCTOBER 1958

possible to perform this surveyduring the time available using

conventional methods. Thus, thecommander of the EngineerGroup decided to utilize theSioux helicopter to assist in thissurvey. It was completed in ap-proxima ely one-sixth the timeestimated for a ground survey.

These were operations con-ducted in peacetime. Naturally,we cannot hover over the target

in combat conditions to accom-plish our mission, but a greatdeal can be done behind the linesin such operations as positionarea survey and connecting survey.

These are only a few illustrations of how the helicopter canassist the surveyor. In addition

to field artillery survey, theArmy is conducting mappingsurveys throughout the world,and helicopters are already as-sisting in this work. However,the degree of accuracy requiredfor mapping survey is such thatthe method of utilizing the heli-copter as an aiming point willnot give satisfactory results, and

their primary use to date hasbeen in the transportation role.The essential elements of ac-curacy in utilizing the helicopteras an aiming point are: that the

pilot be exactly over the selectedpoint and that he be able to de-

termine his accurate altitude.The advent of the absolute alti-meter or hovering indicator )could increase accuracy a greatdeal if the point on the groundis readily recognizable to thepilot.

Until such instruments areavailable, s 0 m e improvementover a pure pilot judgment

method may be found by utiliz-ing field expedient bomb sightswhich will allow the pilot or ob-server to determine his locationover the check point more ac-cura ely. An example of the typefield expedient considered wouldbe an empty 105 shellcase cut offto form a hollow tube with across hair sight fastened in the

case and mounted in a gimbalsto allow it to hang straight downfrom the side of the cockpit.Such a simple sighting arrangement could be used to fix posi-tion more accurately than bypure estimate. t is believed sufficient improvement in accuracycould be obtained by a refineddevice of this type to permit

aircraft to sight points in map-ping work. If this be true, thousands of hours of effort expend-ed in jungles, swamps, and otherdifficult terrain could be avoided.

CORRECTIONIn last month's DIGEST, we stated that Post U S. Army Airfield was named for

Wiley Post. Factually, as many readers pointed out, Wiley Post was but 17 years of

age when Post U S. Army Airfield was established by the Signal Corps in 1917 andnamed in honor of t Henry B Post, 25th Inf, an early Army Aviator who lost his

life while attempting to establish an American altitude record in the Wright Model

C. He was the twelfth Army officer to be killed in air crashes.

18



Pride ills Local Pilot

Maior Jerome B Feldt TC

HAVE YOU EVER read a headlinelike the above? t is doubtful

that you have, but that headlinewould probably tell the wholestory on many accidents. Let ustake a typical crash story and

see what pride has to do with it.John Farmer crashed near his

father's farm late yesterday aft-ernoOll- Witnesses stated that theaircraft had flown over the farmseveral times at a very low alti-tude. On the last flight, the air-craft started to gain altitude andheaded in a northwesterly direc-tion. t seemed to stagger n theair for a moment, then crashed

to the ground and burned. Mr.Farmer had recently been issuedhis flying license at the local air-port. He is survived by his father,IUother, and one sister.

What did pride have to dowith this accident? Pride justabout tells the whole story.Young John had just learned tofly, and he couldn't wait to showoff his new skill to his family.He flew low over their farmhome so that his family mightsee him. In his excitement andexuberance he forgot everythingbut his pride. He leaned back towave to his family as long aspossible and in so doing pulledthe stick back; the aircraftstalled, then crashed. Anotherpilot killed by pride.

We are prone to say, Oh yes,tha is just buzzing like we alldid when we first learned to fly.We no longer do such thingsthough.

Now let us consider the olderpilot for a minute. To illustrate,take the case of an Army maj or

who has just received an assign-ment to command an Army aviation company. He is a SeniorArmy Aviator, 35 years of age,with 3,500 hours flying time and5 years of experience. Will the

Major try to impress the younger aviators in the company? Ishe apt to use his experience asan aviator to accomplish this?They certainly are watchinghim.

One day the Operations Officerasks the Major when he wouldlike to have his area checkout.The Major replies that he doesnot have the time right now buthe will get around to it in a fewdays. A week or two goes by andhe still has not been checked out.

If the Operations Officer isanxious to make a few points hewill probably say something likethis: Major, I have signed offyour check ride as I know thatyou are busy. Besides it wouldjust be a waste of time for youwith all of your past flying experience.

The Major answers, O.K.Thanks very much, rather thaninsisting that he be checked asother pilots are.

A short time later, when the

Major Jerome B. Feldt wrotePRIDE KILLS LOCAL PILOT whileattending the Army Aviation SafetyCourse at the University of SouthernCalifornia He is presently assignedto the 3rd Inf Div USAREUR. Viewsexpressed in this article are the author s and are not necessarily those ofthe Department of the Army or of theU S. Army Aviation School.-TheEditor

19



OCTOBER 1958

Major is out getting his fourhours for the month he inad-

vertently flies low over an activerifle range. He crashes a shorttime later; the aircraft is badlyburned and the Major is killed.The accident is likely to be writ-ten up as cause unknown butit is suspected that the aircraftor pilot may have been hit by abullet that richocheted from therifle range. I believe you will

agree that pride played an im-portant role in this accident. Aproper checkout to identify allof the danger areas may havesaved his life.

When we report to the flightline late for a proposed pas-senger flight and rush throughour flight planning listen to theweather briefing with one ear

and skip the preflight entirelyrather than admit that we werelate we are risking our necksand that of our passengers tosave our pride.

Many times pride has joinedforces with foul weather to killand maim. The pilot encountersweather which is beyond hislimitations and the limitations

of his equipment to negotiate.Rather than abort the flight andadmit to his passengers that hehas to make a 180 turn he en-ters the weather. You can guessthe rest. Even though by somemiracle he is successful the riskinvolved is not justified if onlyhis pride is lost. There may beother factors that would justify

the risk but it is doubtful thatmore than pride is involved inmost decisions to enter foulweather with which we cannotcope.

I believe that pride enters into

20

all accidents to some degree.How about the unit maintenance

officer or unit commander whoallows aircraft requiring mainte-nance to fly so that his availa-bility rate looks good? r thepilot with a bad cold who doesnot report to the flight surgeonand ruptures his ear drums onthe next flight? Or the pilot whohas a good scrap with his wifejust before a flight and is so

mentally preoccupied that hefails to notice that he has onlyone tank full of gas and runsout about half way to his des-tination? They all have allowedtheir pride to overcome theirtraining judgment and plaincommon horse sense.

Since pride itself is not neces-sarily a bad characteristic there

must be some ways it can helpus. There re many.A mechanic who a I w y s

proudly maintains a clean air-craft quite likely has a safe one.If he cleans every part of hisaircraft he is sure to have atleast looked at every part. Wemust assume that if he looks atit he will be able to recognize

discrepancies and correct themor call them to the attention ofhis supervisors for correctiveaction. We also know that if anaircraft is clean it will createless drag and be more efficientallowing greater fuel reserve fora given flight.

Pride can be our greatest allywhen used correctly. Pride is a

great motivating force and hascaused men to make great sacri-fices and to perform unbelievablefeats. t can be used to ad-vantage or disadvantage inaviation flight safety.



OPERATION GRASSHOPPER: Army Aviation in Korea, 1950-53 -Dario Politella The Robert R Longo Co., Wichita, Kan., 1958.

4.95)

Reviewed byMaior Byron H. Brite

United States Army Aviation School

At last the daring exploits of the GRASSHOPPERS in the service ofcommanders and their troops have been recorded for the benefit of all whohave a personal or professional interest in the vital functions of Army Aviation. Whether one is merely curious about the dramatic events in Korea during this period or is a serious student who acknowledges that preparation forthe future merits an examination of the past, Dario Politella has providedvivid information and food for thought. Only an Army Aviator could tell thisstory with adequate appreciation of the operational methods and difficulties

associated with the enemy, terrain, weather, and logistic requirements.In the numerous anecdotes which are the substance of the book, credit

is given where it is due- to the personalities who performed valiantly indoing their duty as they saw it. f it appears that the author has made an

effort to reflect the glory accruing to the individuals who carried the load,let him. Who would deny them?

Yet, it would be superficial to regard the author's work as just a collection of the deeds of the many individuals cited. Commanders and staff officerswho have not been fully aware of the capabilities and operational problemsof Army Aviation have the basis for new insight awaiting them within thesepages. The many military personnel who were served and supported by Armyaircraft during the Korean conflict or WW II will have renewed appreciation

of those events.Nonmilitary readers will be stirred by the various dramatic actions. Thenames of such primary landmarks as Punchbowl and Heartbreak Ridgewill recall the suspense and excitement generated by the efforts of our troopsin battle there. Frequent reference to the maps is recommended so that theincidents described may be placed geographically. Reading of the truce talksreminds us of the Reds' strategy of waving the white flag while preparingfor a renewed offensive.

The Chronology Glossary and Album are of value for their convenientlisting of the primary events during the period of 25 June 1950 to 3 August1953, for the colorful vocabulary of the Army Aviator, and for the picturesof aircraft, terrain, and operational conditions.

In the words of General Mark W. Clark, American servicemen in futuredecades will owe a great debt to the dauntless pioneers of Army Aviationwho learned their skills in World War II and developed them beyond allexpectations on the bloody peninsula of Korea. This book, which is authenticthough not a history text, -portrays the employment of those skills by manyof the people who possessed them.

Book reviews appearing in this department do not necessarily reflect theopinions of the Department of the Army or of the U. S Army Aviation School.The Editor

2



CERTAIN PSYCHOLOGICAL REACTIONS can adversely affect the flyingability of aviators. Chief among these forces are frustrations,

which foster problems that seemingly cannot be resolved, and inturn may cause trivial matters to assume exaggerated importanceand undermine confidence in one s ability and judgment. However,an intelligent approach to an objective understanding of frustra

tion can alleviate some of these undesirable conditions. By knowingthe causes of frustration, we are better equipped to make favorableadj ustments.

When complex individuals aviators) are confronted with com-plex environment an average day of flying), personal wishes andgoals are often thwarted. Frustration may ensue. From such expe-riences we tend to accept frustration as being frequent and some-what unavoidable. The layman may classify the barriers that defyand deny his desires into six general categories, the most commonbeing impersonal conditions.

Impersonal conditions could include: duty on holidays, an in-efficient groundcrew, a hammer which crushes your thumb, trafficjams, slow moving highway traffic, stoplights, etc. If outside factorsexist with impersonal conditions (such as excessively hot, humidweather) we may become irritable and excited.

Although impersonal conditions are blamed for most frustrations, human beings actually cause more. People may help us toour goals at times but, they too, have personal worries and objec-tives. When their interests oppose our own, someone may be frustrated.

Frustrating human relationships exist in friendship-even marriage. Friends, like wives, are pleasant to have, but they are, afterall, individuals with their own goals. Too often individuals get inour hair or under our skin.

People as lawmakers and lawenforcers comprise a third barriergroup. Civilized persons respect community laws; however, no indi-vidual is too civilized not to disobey them occasionally. Then, theauthority of the lawenforcer frustrates the lawbreaker.

In the military, commanding officers must often deny an indi-vidual s inclinations. In fulfilling their duties as commanders, they

frustrate subordinates. Conflict with superiors and social authorityis more frustrating than conflict with impersonal conditions. Forone reason, human beings are harder to comprehend than inani-mate objects. We expect people to be sympathetic ~ d to cooperatewith our wishes. When they are not, our tendency toward frustration increases because we often o not try to appreciate their objec-tions. When a desired course of action is denied, we often attackthe barrier aggressively. In dealing with human barriers we find

22



MEMO FROM FLIGHT SURGEON

that they can, and often do, fight back. People may cause physicalhurt and feelings of guilt or shame. The initial frustration of being

denied isthen further aggravated by the frustration of defeat.

The fourth general barrier group causing frequent frustrationis personal inability. Victims of this type of frustration are theirown worst enemies. Their goals are defied by the shortcomings oftheir intelligence or physique-or both.

A pilot who loses an eye will be exceedingly frustrated if hecannot manufacture a substitute for his desire to fly. Such frustration is a graphic example of a goal exceeding physical ability.

Lack of intelligence also produces frustration. Individuals oftenaspire to positions surpassing their mental ability. Only when they

have been exposed to their goals do they realize their ineptitude.They are liable to self-recrimination, bitterness, deep-rooted insecurity, and a sense of inferiority to society.

The fifth and sixth general causes of frustration concern conflicting motives and needs. The person who must choose betweentwo desirable courses of action is an example of the fifth category,conflicting positive motives. Both choices are equally desirable;yet, he must deny one by choosing the other. The choice deniedremains in the background and may haunt the individual, causing frustration.

The man who chooses a flying career as opposed to an executiveposition in industry will often return in his mind's eye to the deniedcourse of action, wondering what might have been. Dependingon the circumstance which prompts such reflection, frustrationmayor may not be forthcoming.

The sixth cause of frustration arises from conflicting positiveand negative needs. The frustrations commonly associated withtemptation are included here. The victim is characteristicallygrumpy, tensed, and, in part, physically or mentally lazy. By habithe chooses the easy way or the negative course. He talks of setting

the world afire and is contrarily sunk in inactivity because he fearsunfair competition, failure, or his own inabilities. For some, thesefears frustrate more effectively and permanently than in cases ofthe preceding groups.

Temptation arises when a choice of action conflicts with a person's code of ethics. The temptation may frustrate. If a person'sconscience and needs are equally strong, he may experience severefrustration when choosing between positive and negative needs.Either the desire to be morally correct or the need for illicit gainis denied. If he makes a negative choice and does evil, frustration

will be manifest by guilt of conscience and shame. The so-calledguilty conscience will be proportionate to the individual's character.

Generally, our first reaction to frustration is rational; that is,we attempt to resolve the problem with an intelligent approach.f our initial common sense is replaced by emotion, our reaction

Views expressed in this department are not necessarily those of the De-partment of the Army or of the U S. Army Aviation School. The Editor

3



OCTOBER 1958

then becomes one of aggression, regression, apathy, fixation, re-pression, or escapism.

Do not put all your eggs in one basket. Never be withoutalternate or separate courses of action which will assure somemeasure of accomplishment.

Do not burn the bridges behind you. Alternate and separatecourses of action may necessitate retreat to a better position forthe successful flanking app'roach.

Analyse the possible opposing actions in order to more effec-tively time and execute the approach.

In short, make an adequate estimate of the situation and avoidbuilding up excessive hope and desire for something that is im-properly timed, improbable or even impossible to accomplish.

PUZZL RI GENERAL SITUATION

The 20th Infantry Division has been in I Corps reserve for thepast 10 days. The Division Commander has just received orders torelieve the 55th Infantry Division at 060400 June.

II. SPECIAL SITUATION

It is 040900 June. You are the newly assigned 20th DivisionAviation Staff Officer. You have just attended a division briefingrelative to the forthcoming operation and have received authoriza-tion for direct liaison with the 55th Division.

III. REQUIREMENTS1. What instructions, if any, do you issue at this time?

2. Who should accompany you on a liaison visit to the 55thDivision Aviation Company?

3. What primary interest would you as the Division AviationStaff Officer have during this initial liaison visit?

4 During the visit, to what specific points would you expect themembers of your liaison party to give primary consideration?

5. Upon returning to the 20th Division area, you formulate

plans to effect the relief of the 55th Division Aviation Company.Must you submit these plans for approval, and if so, to whom?

Study the foregoing questions with care and o not peek at thesolution until you have come to a conclusion on each question asked.fter arriving at your answers turn to page 32 for the recom-

mended solution.

4



When the mind is in a state of un

certainty the smallest impulse directs

it to either side. - TERENCE

No one can say with authoritywhat takes place in the mind ofa well trained aviator that causeshim to react to a set of circumstances in a manner com

pletely alien to his training.However experience and statistics indicate that physical andmental fatigue anxiety and uncertainty play major roles. Allof these were present to somedegree in the following accident.

Because a specific type of torque wrench was unavailable atthe unit it became necessary to

fly the Choctaw to another location for a periodic maintenancecheck. The pilot spent 5 hoursinspecting and checking th

Choctaw on the day before theflight including a I-hour testflight.

That night the pilot went outto dinner with friends; he returned to his quarters at 2230hours. The next morning at 0540hours he was on the flight lineready for the flight. He had amaximum of 6 hours sleep as hehad to rise at 0445 hours todress eat travel to the flightline and make preparations forthe cross-country mission.

The pilot declined the offer tocarry a copilot on the assignedmission. It was unknown howlong the necessary maintenancechecks would take at the destination so permission was givenfor him to remain overnight.

He took off at 0614 hourswith a mechanic aboard. The

outbound flight should have required approximately 3lj2 hoursbut due to navigational errorthe pilot arrived at a point 130miles from his destination. Afterlanding and refueling he continued to the destination arriving at 1247 hours. He was inactual flight for not less than5 2 hours on the outbound flight.

An observer stated that although the pilot appeared wearyon his arrival he declined transportation to the nearest eatingestablishment and remained onthe flight line. After maintenance was completed at 1430hours he appeared anxious todepart on the return flight. Hewas delayed for 2 hours dueto his lack of understanding the

The Gray Hair Department s pre-pared by the U S. Army Board forAviation Accident Research with in -formation from its files Views ex-pressed in this department are notnecessarily those of the Departmentof the Army or of the U S. ArmyAviation School. The Editor

25



j t r ~ lu mIu te IV

AND WHEN THE KNIGHT hadflown far to reach his desti

nation, he spake into a smallblack box, requesting of thosewho heard, a suitable path for

alighting. Anda voice spakeinto his ear ,saying:

Alight thee

tot h e

north-west and heedthe wind which

bloweth across that path fromthe port. Its velocity turns theleaf but doth not disturb thelimb.

With this knowledge, t h e

knight slowed his charger anddropped flaps to approximate the

half of one right angle. Hecanted the craft to port andcrabbed for a straight approachto the assigned path. Before heraised the nose, the knight removed all crab and lowered theport wing in a manner that keptthe beast aligned with the path.And when the time came hebrought it into a position that

caused the left foreleg and tailto meet the turf in the same in-

necessary procedures to obtaina flight clearance from FlightService, and by a tieup of communications lines. Another observer sta ed tha the p i lo t

seemed tired and irritable just

prior to his departure at 1613hours.

During the r e t urn flight,thunderstorms built up alongthe route, and heavy rainshowers reduced visibility in the approaching darkness. It seemsunlikely that the pilot main-

26

stant. All was well for this wasindeed the manner written andtalked of in all the kingdom.

T H N T H K N I G H T

FORCED HIS STEED TO' DRO P

ITS RIGHT FORELEG TO' THESO'D

As though to chase its tail,the charger began a turning toport that grew faster and faster.n

great awe, the knight kickedright stirrup to the limit andengaged the brake in like manner; alas, it was to no avail.While the steed skidded over thesod its right foreleg folded beneath. The right wing crumpledinto the ground while its materose higher in the air. And whenits nose was pointing to the di

rection from whence it had come,the craft slid rearwards for fivepaces and slumped to a halt.

The shaken knight dismounted and looked longingly at thesky. For it were better that hewere not found in that place.And he tore his hair and rentthe air with curses, calling uponall to witness the weakness of

the brake and rudder.Before the dust had settled,

tained a listening watch to thevarious radio stations along hisroute, because he failed to makea position report at any time,and weather advisories we r ewarning of the severe thunder-

storms in the area.A motorist observed the Choc

taw following a highway. Hestated that the aircraft enteredan area of extremely heavyshowers, made a 180 0 turn andflew back into a lighter area;then it turned again, and flew



the gray beards arrived; and onewho was wiser than the rest

tossed blades of grass into theair and watched their fall toearth. And when he had seen, hecalled to the others:

"Seek no more, the answer isplain Heed not this talk of weakbrake and full rudder, for theseare blinds that hide the truth."

And when they were gatheredabout him, he spake in a voiceof great wisdom:

"The ways of the bird areknown and thy scrolls tell of thisknowledge. Listen well, lest thoualso forget

"This knight was observed tohave alighted his steed in thecorrect manner for the windacross this path. But then he

forced the bird to lower its rightforeleg. In this manner, by moving the controlling stick to thedownwind position, the knightslew his correction for the portwind and all directional controlwas lost to him.

"Thy bird is like unto theweathercock, and when the winddoth blow, its tail will move

downwind because of the broadness of its surface and the light-

back into the rainstorm. Themotorist further stated that therain became so severe at thistime he was forced to park hiscar because he could not see todrive.

A short time later the Choctaw crashed in a nose-down at-titude. The aircraft began todisintegrate upon initial impact,but continued forward for 71/2

feet on the engine compartmentand main landing gear. At thatpoint the engine was torn loose

GRAY HAIR DEPARTMENT

ness of its weight. And when thewind is cross, thy upwind wing

receives more air because thydownwind wing is blocked froma portion of its air by the upwind wing and the body of thebird. Thus, thy upwind wingdoth produce more lift and dragthan its mate and this would turnthe bird. But this need not be,for thou dost hold in thine handa full measure of correction. If

thou holdest the controlling sticktoward the wind, the aileron ofthy downwind wing doth movedownward and provide the dragthat is greatly needed. In thismanner, the aileron of thy upwind wing doth move upward tohalt the lift and drag that isthere. Heed well that as thyground roll slows, the bird would

more like to turn and a greatersurface of aileron is so r i yneeded.

"Fear not for thy downwindleg remaining in the air, for asthe bird doth cease to fly it willwalk on all legs without thyaid."

And the gray beards calledfor their cups, for they were

very wise and such was the custom in those days.

from its mounts, and the mainrotor blades scraped the ground.The fuselage continued forward,turning and rolling to the rightside. The tail section parted onthe left side, and the aft sectionand pylon assembly folded to theright at a ° angle to the fuselage. 'The main rotor head andtransmission fell to the right,landing in an inverted positionand ripping the top of the fuselage along the left side for a distance of 12 feet. The fuel cells

27



OCTOBER 1968

ragedy of errors

were torn open at impact, and afire developed that was confined

to the immediate area by theheavy rains and water standingin the impact area.

Both the pilot and mechanicwere thrown violently againstthe forward part of the cockpitand received multiple injuries,anyone of which could havecaused instant death. As thefuselage ripped open, the me

chanic was thrown clear, but thepilot was caught in the wreckage.

This pilot exceeded his capabilities in attempting to flythrough an area of extremelylow visibility and ceiling.

Mental and physical fatigueare believed to have been important factors in this accident.This condition was induced byexcessive flying within the 13-hour period prior to the accident, and intensified by the ten-sion and anxiety caused by navigational r r 0 r s, turbulentweather, lack of proper rest, andthe desire to complete the flight.

28

Any pilot who pushes himselfto the limits of physical and

mental endurance invites disaster. Army Aviation requiresmental alertness and physicalagility. These qualities are notpresent in a tired and irritablepilot. Remember this the nexttime YOU'RE in a hurry to gethome

COOL HE D S VES CHICK S W

Contrary to popular belief,those charged with the responsibility of publishing accidentcause factors do not enjoy placing the blame on aviators. Unfortunately, in a high percent-age of accidents, that s the waythe ball bounces. When a chancecomes along to give an aviatora pat on the back for a job well

done, it s a great pleasure toshout it out in our loudest voice.More can be learned from reading the positive account of whatan aviator did to avoid damageto his aircraft than a negativeaccount of what he failed to do.

First Lieutenant Wallace G



OCTOBER 1958

Blaisdell, Fort MacArthur Cal.,was on a service flight to ferry

three passengers from a Nikesite to Fort MacArthur. Aboardthe aircraft were a mechanic andthe three passengers.

Lieutenant Blaisdell made histakeoff from the Nike site andflew across the San FernandoValley. Approaching the SantaMonica mountains on a souther-ly heading, he increased power

to clear the mountains that werea mile ahead. As the power wasincreased, the engine startedbackfiring and rapidly lost power.The terrain below the aircraftwas heavily wooded and hilly.The only possible landing sitewas a narrow firebreak road ina valley to the right.

Lieutenant Blaisdell went into

immediate autorotation ndmade a 180 turn to the road, selecting the widest portion as atouchdown point. All switcheswere turned off at approximately

1 feet above the road, and anormal autorotative landing was

made. The aircraft rolled forward for a distance of 15-20 feetand the main rotor blades strucka heavy bush. The three rotorblades were damaged near thetips; this was the only damageto the Chickasaw.

Inspection of the engine revealed that the exhaust rockerarm on No. 7 cylinder assembly

was missing. The castellated nutwas stripped from the valverocker shaft. The cause of engine malfunction was attributedto overtorquing of the nut tostop an oil leak.

The clear thinking and quickaction of this aviator prove thathe was prepared to deal with anemergency. This preparation can

result only from TRAINING,PRACTICE, THOUGHT, ANDHARD WORK.

Well done, Lieutenant Blaisdell

ool he d s ves hickasaw

29



throttles of the tw controlquadrants is long and flexible.

When the front throttle is open-ed, pressure to close the rearthrottle causes compression onthe rod and it bends outward.This makes it impossible for theinstructor to override the stu-dent for throttle control. Therehave been instances where therod bent outward and upward,jamming itself over the tuning

handle of the radio. When thishappens, the instructor mustlean forward and pull it loose. Itcan be readily seen what wouldhappen if this occurred at acritical time.

GRAY HAIR DEPARTMENT

A correction has been de-termined for this peculiarity of

the Bird Dog. All School aircraftof this model have been modifiedwith a bracket mounted midwaybetween the throttle quadrants,and a fix, worldwide, has beensent out from TSMC. On aircraftthat have not yet been modified,pilots should be aware of thispotential danger and be guided

accordingly.During

dual in-struction flights, it should beunderstood at all times who hascontrol of the throttle. I've gotit, can save sweat and the tax

payer's dollar.

Recommended ReadingUNARMED INTO BAnLE-Mai Gen H. J Parham and E M. G. BelfieldWykeham Press, 85 High Street, Winchester, England

Reviewed by

Dario Politella

The British have apparently done a

much better job publicizing their L

pilots than we have. This book ap

peared in 1956, published under the

auspices of the Air OP Officers Asso-

ciation. t was three years in thewriting.

General Parham, who as an Artil

lery captain in 1933 advocated air

OPs, and Belfield, a former artillery

man-turned-author, are able writers.

Theirs is by far the most complete

treatment of the history of air OPs

this writer has read. The authors ,

have traced the development of air

observation from its earliest inception

in 1783 through World War II. The

detailed history of the British air OP

pioneers and the struggles they en·

countered in the establishing of an

air OP in the British Army makes

interesting reading.

The frustrations of our British

counterparts are so reminiscent of

our own that for this reason alone,

the book is worth reading. I t will come

as no surprise to veteran Grass

hoppers in this country that inter

service misunderstanding existed be-tween the RAF and the British Army.

The situation was further complicated

by the opposition, as well as lack of

understanding and outright indiffer

ence, of their own ground officers.

The book reveals that the first ex

periments with air OP were held in

1938. These were witnessed later by

Major General Robert M. Danford,

then Chief of U. S. Artillery, who

subsequently directed Lieutenant

Colonel William W. Ford to investi

gate a similar program.

All told, the record makes inter

esting reading. This book should be

included in every Army Aviator's li-brary.

31



On the basis of the factual information contained in the PUZ-ZLk R on page 24, the recommended solution is as follows:

1 Immediately alert the Aviation Company Commander concerning the forthcoming move. Upon receipt of this order, he willissue necessary orders to the remainder of the company.

2. The liaison party should include the Aviation Company Commander Communications Officer, Maintenance Officer, and theOperations Officer.

3. Your primary interests would be:a. The aviation situation in the 55th Division s zone of

responsibility.b. Significant enemy activities, especially those most di-

rectly affecting Army Aviation.c General disposition of units of the 55th Division.d Logistical Aviation problems of the 55th Division.e Present employment of elements of the 55th Division

Aviation Company.f. Formulation of a coordinated plan to effect relief at the

prescribed time.g. Possible exchange of some supplies and equipment with

the 55th Division Aviation Company (communication facilities,drum-for-drum exchange of POL, etc.)

4 a. The Aviation Company Commander will discuss with theCompany Commander of the 55th the details of the physical occupation. Some points to be considered are the phasing in and out ofaircraft and the times for final occupation by the various elementsof the company.

b. The Communication Officer will be primarily concernedwith the continuity of communications, both wire and radio. Arrangements can be made to utilize wire facilities already in place.

c The Maintenance Officer will be interested in the facilities for maintenance. Some item-for-item exchange can be arranged

to avoid double transportation.d. The Operations Officer will become responsible for con

tinuity of operations during the move. For security having Aviators and observers of the 20th Division fly with their counterpartsof the 55th until the relief is completed will be a function of theOperations Officer.

5 Your plans must be submitted to ACofS, G3, for approval.There are, of course, many other things to e done. The fore-

going were presented as examples of the problems involved. Hopeyour thought has been stimulated. Like this type of puzzler? Let

us know. The Editor

THE NEW RULE

Effective 15 August the new altitude separation rule went into effect. The rule

begins 3 000 feet above ground. At that altitude the rule is based on altitude abovesea level. If you take off from a field t 1 000 feet elevation with your altimeterset to field elevation you would go to 4 000 before the rule took effect.

32



Ground that once knew thethud of hoofs of caval ry

horses now mutes the roar of

helicopter engines at Mar

shall U S. Army Airfield, Fort

Riley, Kansas. According to

Army Aviation Flight Infor-mation Digest it has VOR115.4 mc) and a Non-Direc

tional Radio Beacon 317 kc,0290 , 1.8 nm to field); fuel,

minor engine and aircraft re

pairs, and storage are avail

able. Stationed presently atMarshall AAF are: 1st Divi-sion Aviation Company, 71st

Transpor ta t ion at ta l ionHel), 81 st Division Aviation

Company Lt Hel), and 545th

Transportat ion DetachmentCHFM). Extensive helicopter

training is in progress, andunit training continues with

enthusiasm, energy and im-

agination, aimed at the mis

sion: Success in combat. Mar

shall AAF is named in honorof Colonel Francis C Marshall,Cavalry.

Above and LeftView of Field

and Hangar

Army Aviation Digest - Oct 1958

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Transcript of Army Aviation Digest - Oct 1958