Army Aviation Digest - Mar 1964

8/12/2019 Army Aviation Digest - Mar 1964

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UNITED

DIRECTOR OF ARMY AVIATION ACSFORDEPARTMENT OF THE ARMYBrig Gen John J. Tolson III

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COMMANDANT U. S ARMY AVIATION SCHOOLMaj Gen Clifton F. von Kann

ASST COMDT U. S. ARMY AVIATION SCHOOLCol Robert F. Cass idy

EDITORIAL STAFFCapt Richard C. AnglinFred M. MontgomeryRichard K. TierneyWilliam H. Sm ithDiana G. Will iams

GRAPHIC ART SUPPORTH. G. LinnH A. PickelD. L CrowleyJ. Joh nson

USABAAR EDUCATION AND LITERATURE DIVPierce L WigginWill iam E. CarterTed KontosCharles Mab iu s

RMY VI TION1GESJMARCH 1964 VOLUME 10 NUMBER 3

CONTENTS

LETTERS . . . . . . . .. ... . . . . . . A PERSPE CTIVE ON FffiEPOWER AND MOBILITY, Cen Ea rle C.Whee ler . . . . . . . . FROM RAGS TO RICHES . . .. . . . . THE CASE FOR SELF DISCIPLINE . . . . . . . . . USE THEM ALL, Capt Robert vV McCaskey . ; . . . . . . . . . . . . . . . . FLICKER PHENOMENA, Capt J. C. Rothw II . IFR (I FOLLOW ROADS), Lt Joseph B. Swartz . . .. .V/STOL OPERATIONS, R W. Ha rker and A J. Heyworth . . .IF THE SHOE PINCHES, Col Robert M. Hamil ton . . KITCHEN TESTING ARMY AIRCRAFT A D COMPONE TS,

Capt John T. Treacy . . PERSONAL SAFETY TIPS . . . . .. . . . THE DA NGERS OF IMPROPER APPROACH TECHNIQ UES,Capt Jody L Williams .. . . . . . . . DEM BOlDS HAVE GOTTA GO, ' i il liam H . Smith . . . . . ARRIVE ALIVE, Capt William L Shackelford . AR ADMAC, Ted Kontos . . . . .INVISIBLE STRING, Capt Malcolm McDonald . . . . . CRASH SENSE . . . . . . .. . . . . . . . .

The mission of the U. S. ARMY AVIATION DIGEST is to provide information ofoperational or functional nature concerning safety and aircraft accident preventi on , t rainimaintenance, operations, research and development, aviation medicine, and ot her r ela te d daThe DIGEST is an official Department of the Army periodical published monthly unthe supervision of t he Commandant, U. S. Army Avia t ion School. Views expressed herare not necessarily those of Department of t he Army or the U. S. Army Aviation SchoPhotos are U. S. Army unless otherwisf specified. Material may be reprinted giving creto the DIGEST and to the author, unless otherwise indica t ed.Articles, photos, and items of interest on Army Aviation are invited . Direct communit ion is authorized to: Editor in Chie/. U S Army Aviat ion Digest. Fort Rucker. AlabamaUse of funds for printing of this publication has been approved by HeadquarteDepartment of the Army, 27 November 1961.To be distributed in accordance with requirements stated in DA Form 12 .


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Sir:As one of your many readers, Iwould like to thank you for your excellent coverage of aviation safety,in particular those items which indicate how certain accidents mighthave been prevented . I would like tosubmit an experience which showsthe value of such information.One night I was ft.ying a UH-1Dwhen the proverbial moment of"stark terror" struck-audio warning blasting in the headset , rpmwarning light all bright and shiningand the engine tachometer restingon zero. Had I not read in theAVIATION DIGEST of an earliersituation in a UH-1D where engine

tachometer failure tr iggered thesesame warning devices, I too wouldhave entered immediate autorotation and been exposed to extensivedamage upon touchdown as oc-curred in the accident cited.However, having knowledge of thissimilar situation and the recommended procedure of checking allengine instruments while ensuringconservation of rotor rp m , I wasable to conclude that the engine wasfunctioning and to verify this conclusion by gingerly increasing pitchand observing no loss in rotor rpm.Although the cost for this accidentwhich never happened cannot be accurately estimated , I for one wish topersonally thank you for this typereporting.E P. LUKERT, JR .Maj InfAdvanced Studies DivisionUSACDCAVNAFt Rucker, Ala.

The earlier situation referred toby Maior Lukert was discussed inthe article EMERGENCY SITUA-TIONS Jan 64 issue.

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Si r ,We were all very pleased to readthe fine articles written about thehistory and growth of Army Avi-ation .I wonder i anyone has given anythought to the idea of these articlesbeing compiled into a book?I know there are a lot of us thatwould like to have a copy to lend toour Air Force and Navy buddies.

JAMES B. KELLYCaptain Inf The articles were combined andpublished along with additional in -formation in THE ARMY A VATION STORY in October 1963.Copies are available f r om TheBook Store USAAVNS ($4.75 plus10 postage .

Sir:In the October issue an article ap pears which must have raised sev-eral eyebrows and caused several"whews" where Army Aviators gather. "Where There 's Smoke" is thearticle , and the aviators are extremely lucky to be alive.I am a little surprised at the ac tion and extreme reluctance of theIP to either declare an emergencyor request approach clearance assoon as the smoke was noticed. Thefact that weather was 100' andmile visibility indicates that the IPeither held a special instrument rating or violated the 300' and 1 milerequirements for fixed wing takeoffs.In the beginning, weather conditions were somewhat lower thanSAFE (versus legal) for instrumenttraining. No course of action was

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available in the event that something should go wrong. The takeoffwith weather considerably belowlanding minimums would requiregoing to the alternate should troubleoccur. The t ime required to ft.y to thealternate (Western France) wouldbe far in excess of battery endurance should the generator fail.The aviator states that theyturned off the radios to preservepower but it didn't do any goodsince the battery drained down anyhow. The fact that aU radios wereworking properly should have indicated trouble somewhere else. Turning off the MASTER SWITCH wouldhave isolated the battery and preserved whatever power was left. Thiscould possibly have enabled them touse the ILS for their below minimum approach. KNOW YOUR AIRCRAFTThe reason for continuing theft.ight rather than request an immediate approach was that the ideaof an approach in such miserableweather didn 't appeal to me.Weather too miserable to land in istoo miserable to take off in withoutan alternate within 30 minutes ft.y-ing time.

The mistakes made are listed below in order.1. Takeoff below landing minimums for a low priority mission.Building weather time will make animpressive total. This and a dimewill get you a cup of coffee nearlyanywhere .2. Not requesting an immediateapproach while the radios were stillworking. Making a below minimumsapproach is an emergency maneuverand MUCH safer with an ILS localizer needle than just a marker beacon light.Continued on page

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General Earle G Wheeler Chief of Staff United States rmy

Perspectiveon Firepowerand obility


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A RMY OPERATIONS nowL\ seem far removed in everyfrom those of the 1800s

the actual changes are in deand not in principle. In

remnants of some of the deare still around: in Viet

m the bow and arrow and thestill employed on oc-by the Viet Cong though

as effectively as they werey the great warrior tribes of

American Indian.I think that we can discount

as decisive fac-war, but their

use illustrates the factthe dangers with which the

oldier must contend increaserather than d iminish over thecenturies. It is unlikely that aman-of-war under s i lo r thatthe early types of aircraft willever be employed against modern sea and air weapons systems.However the bamboo sp ike-whose use in war dates far backinto antiquity-is still a dangerous reality to our Army advisorswith the Vietnamese forces.

My purpose is to present abrief perspective on the conductof land combat operations whoserange today can extend fromambush on a jungle trail tonuclear warfare. These views

center on the modern application of the cIa ic principle thatsuccess in battle stems in greatdegree from superiority in themeans of mobility and its employment for effective maneuver. The end purpose of maneuver is accomplished through fire-power, and the exercise of theseinterdependent actions re ts inturn upon control through re liable and fast systems of communication. As you know theseelements are more succinctlydescribed as the ability tomove shoot and communi

cate.Throughout history, the ar-


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mies that have come up with thebest solutions to these three re quirements have, in general,won the battles and the wars. Asbackground, let us look at someof the solutions that haveevolved during the 188 years ofour Army.This survey can start withGeneral Washington s urgent appeal for Congressional authorityto include cavalry in the Continental Army establishment. Hesupported this appeal with thestatement that the war could notbe won without the mobilityand shock action of cavalry. Hisviews on artillery were equallystrong. He insisted on at leasttwo guns to support each in fantry battalion and did everything within his power to obtainthese guns and to standardizetheir calibers.

The combination of infantry,artillery and cavalry elements

into a combat arms team wasfirst proposed by von Steubenafter the Revolution. The con-cept was employed effectivelyby Wayne in the Northwest inthe 1790s. Our present ROADdivision and the makeup ofmodern Army structure of 16divisions follows the same principle of combinations of thecombat arms in which firepowerand mobili y are balanced. Iemphasize this principle of balance which today means, ineffect keeping the means of mobility abreast of the advances infirepower. We intend to avoid arepetition of a situation whichdeveloped in World War I whenthe machinegun and artillerybrought maneuver largely to ahalt and resulted in the carnagein battles such as those on theSomme and in Flanders. Late inthat war, the tank began to re dress this balance and to restore

mobility to the battlefield.The organization, materiel

and doctrine of the maj or armiesthat began World War II represented their respective conclusions on the lessons of WorldWar I concerning firepower andmobility. As you know, the conclusions reached by the GermanArmy proved to be decisivelythe best, and its ground forcesthat were only partially mechanized-overwhelmed Belgiumin 18 days and France in 39 daysThese feats present a startlingexample of the impact of doctrine in a situation in which themateriel on the opposing sidewas roughly equal. The GermanArmy in 1940 had neither quantitative nor qualitative superiority in armor. But the Germandoctrine of grouping tank andmotorized divisions into powerful mobile combined arms teamssupported by tactical airpoweproved overwhelmingly superioto the doctrine of dispersal oarmor practiced by the Allies.

Military history contains manysimilar examples. I use this onebecause it has occurred withinthe memory of many of us. Ipoints up the fact that we cannot afford to be wrong in ouconcepts of the use of firepoweand mobility in ground combatoday. World War II afforded ussome time to profit by its earlylessons. We will not have thiopportunity should we be attacked again.

The airmobility tests now underway to determine how theadvance3 in light aircraft capabilities may be employed fotroop maneuver and supply onthe battlefield are in keepingwith the reality that we cannoafford to lag in either the material means of mobility or inthe doctrine for its use. No particular foresight is required tosee the growing potential of th

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vehicle for this purpose-norpresent limitations. This po

has not just suddenly apit has been building up

the years in the familiarthat is followed by every

advance in the materialof conducting war. Atoday in theof the execution of thisas a result of the accel

pace of technology. Forgunpowder was known

Europe in the 13th century,it did not come into general

until the 16th cenBy contrast, the tank that

its beginnings in World Warwas developed into the major

weapon of World War II 20 years later.Aircraft were used in WorldI in the battle area primar

for visual reconnaissancespotting. More effi-

light aircraft were used insame role in World Wa II. A

but little-noted operaalso took place n the early

of World War II thatcounted a milestone in

airmobility. This oc-on the first day of theoffensive in the west

involved the landing of eleof an infantry battalion

the Belgium defensiveby light liaison planes that

each,the pilot. The operation

imaginative and daring, butwas soundly based upon a

linkup of the lightlyinfantry with

advancing armor. Under thethat prevailed, the

was within the caof the machines thenand it contributed tobreakthrough. Whileby the momentous

in which it played a relapart, this early ex

of airmobility for infantry

provides important guidelines.Its salient points were an unexpected landing in a weakly defended area and a mission suitedto the men and armament thatcould be lifted. This is a soundpattern for any military operation.

Other more familiar milestones are the wide use of helicopters for medical evacuationin Korea and the present mobility support being given byArmy and Marine aircraft to theforces of the Republic of Vietnam.

Our Army aircraft today arefar advanced over the type usedto air-land the German infantryin 1940; our helicopters in Vietnam are advanced over thoseused in Korea just 10 years ago .This advance will continue. Thequestion is: How can the steadilyimproving means of mobility beemployed to maximum advantage? We cannot delay in determining as best we can theanswer. This need has resultedin the allocation of an appreciable slice of Army resources tothe airmobility tests.

In summary this is the Army sperspective regarding mobility:our overall purpose is to employevery means now available andthat becomes available to enablethe soldier to gain the advantageof position in battle, and to increase through speed the impactof his maneuver. These meansstar t -as they always havestar ted-with that reliable system of locomotion, the soldier sfeet propelled by his own legpower. Those from field unitscan attest that the developmentof this means of mobility is notbeing neglected. To this has beenadded the modern personnel carrier, which in combination witharmor and employed where appropriate, represents a quantumjump in mobility and firepower


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over troops on foot.It is our conviction that thenext significant addition to mobility is through Army aircraft.We believe that there are ap propriate operations for aircraftof this type in land combat situations ranging from counterinsurgency to general war. The airmobility role must be soundlyconceived within the capabilitiesof men and machines for eachtype of operation. To misjudge itcan be as critical an error as wasthe Allies' misjudgment of theuse of armor early in Wor d WarII. The officers and men takingpart in the tests now underwayat Fort Benning have a missionas important as any in the Armytoday.

Regarding the human elementof the Army, the requirementtoday is the same in principle asthat established by Major R ogersin 1759 for his Rangers, whom hedirected: Have your musketclean as a whistle, hatchetscoured, sixty rounds of powder

and ball, and be ready to marchat a moment's notice.

The march for the 1964 soldiermay involve mounting the troopcarrier planes of the ir Forceto take him to the other side ofthe world, but the requirementfor a general state of materieland mental readiness to moveout has not changed. The individual ingenuity and resourcefulness that Rogers demanded ofhis men is still in force. It is anapparent paradox, that as thesize of our Army has grownfrom thousands to hundreds ofthousands, the responsibilities ofthe individual soldier have notdecreased. The Army is far frombeing a faceless mass that re quires only blind obedience. Thedispersal on the battlefield inmodern war places-if anythingeven greater demands on the

initiative of the soldier than before. Missions that include thesupport of Allies throughout theFree World give our 960 000-man Army, proportionally, th e

widest field of operations in itshistory. Far flung and diversetasks require that commandersand units have maximum leewayin the carrying-out of their assignments. In recognition of thiswe have a continuing programto remove directives and regulations that restrict commandersunduly in the exercise of judgment in the use of the resourcesallotted them. This is on thebasis that if we expect a command to act forcefully and withjudgment in carrying out a critical assignment in an emergencysituation on the other side ofthe world, we can trust it to handle routine operations.

From the vantage point of theposition that I am privileged tooccupy, I can see how the Armyoverall, is meeting its heavy responsibilities. Without discounting or overlooking areas that canbe improved, I say that this performance measures up to thebest standards establi hed in 188year of history.

U. S. R Y VI TO DIGEST


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romRagsTo RichesD DRING THE depression, enterprising feedcompanies boosted ales and also helped thepoor farmer s wife by bagging their products incolorful cotton print, good enough to be used asdress material. When the depr ession was overthey quietly switched to paper bags, which arecheaper and better suited for the job.

Since that time, a steady stream of new paperproducts has replaced many cloth items. Facialtissues have all but replaced fancy ladies hankies.Paper napkins are an accepted fact. Even thelinen tablecloth now has a competitor in the largeand expensive-looking paper table cover that canbe used once and thrown away.

Years ago the first mechanic to get his handsgreasy grabbed a piece of old cloth to wipe themwith, and rags have been used around machineryever since. Now a new product on the marketmay replace wiping rags. t is a rayon-reinforcedpaper wiper that is lint-free, soft, pliable an d , likewiping rags, may be dipped in ordinary solvent,wrung out, and reused.

The new paper wipers have a decided storagespace, weight, and handling advantage over wip-Handy chart for quick computation to see i newwipers will benefit your activity logistics or

costwiseQuantity144)000 Rags144)000 WipersQuantity

144POO Rags144)000 Wipers

Handling Units Gross Weight72 Bales 36)000 lbs144 Cartons 5)760 lbs

Storage Space2,160 cu t864 cu t

Cost GSA Catalog 7)4882,808

ing rags. One case of the wipers occupies approximately 6 cubic feet, weighs ap roximately 40pounds, and contains 1,000 uniform wipers. Incomparison, five bales of wiping rags occupy approximately 15 cubic feet of space, weigh approximately 250 pounds, and contain approximately1,000 usable rags.

Paper wipers may be an advantage to the government costwise, especially in areas where ragsare used instead of contract wiping cloths. A baleof wiping rags has about 200 usable rags and costs10. This means each rag costs 5. Two hundredpaper wipers cost less than 4, which is less than2 each.

GSA carries two sizes of the wipers. FSN 7920-823-9773 is 13 s x 16 inches and is for generalshop use. FSN 7920-823-9772 is 13 a x 22 inchesand is for heavier wiping needs.


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THE CASE FOR SELF DISCIPLINEYOUR HONOR, during the course of this hearing, we will prove beyond the shadow of adoubt that some aviators, in the performance oftheir flying tasks, extend themselves beyond thelevel of their capabilities and the capabilities ofthe aircraft they fly.

The people introduce into evidence as exhibitA, DA Pamphlet 95-11, 'Field Maneuver Sense.'8

Reading on page 11 of this pamphlet, we find:. . . the pilot of a Bird Dog was in such a hurryto put down on a road beside his CO s jeep that hefailed to make a proper wind check. The CO . . .helped pick him up out of the ditch where he wasblown by a 20-knot breeze. . . . Far worse befellthe pilot of a UH-l who took off carrying a load ofpassengers without paying attention to either the

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density altitude or his weight and balance limits.,On the way to observe a tactical exercise he m ea downwind turn, hit a cliff, and plunged into alake. All on board were killed.

'These and other maneuver-spawned accidentsdiffer in detail. In one respect they are identical:hasty precipitate action caused th m all.

'One thing which helps keep a pilot on his toesduring maneuvers is the normal apprehensionwith which every healthy flying man approaches atricky task. The sensation of having a flock of butterflies in his stomach, sometimes referred to asBridegroom's Syndrome, puts a chap on notice anunusual situation is in the offing. The time hascome to hold with a death grip to his self-controlto keep his emotions from taking the bit in theirteeth and running off-like the man in the poemwho jumped on his horse and galloped away in alldirections at once. Instead, normal apprehensionserves as a blinker light, a warning to move withcaution. Firmly in charge of the situation, ourbutterfly-heeding airman makes his moves in thefull light of his planning and training, knowledgeof the situation, and capabilities at the moment.'

Having read from exhibit A, we will now proceed to two recent examples to prove our case.The people call as their first witness the recorderof an aircraft accident investigation board whichwas called to investigate a fatal 0-IA accidentduring a field maneuver exercise.

The recorder will take the stand.Mr. Recorder, in your own words, please giveus a description of the accident.

At approximately 0805 hours, the 0-IA aircraft departed a tactical airstrip on an assignedaerial relay and reconnaissance mission. The aircraft crew consisted of a pilot and observer. During the course of the flight, this crew saw a flightof UH-l helicopters in trail formation at approximately 0935 hours. The 0-1 flew parallel and inthe same direction as the helicopters, at an altitude of 20-50 feet over the trees.

On orders from the flight leader, one of thehelicopters pulled out of formation and began toovertake the 0-1 from the rear in an effort to 0 bserve its tail number.

For what reason?This was standard procedure for reporting to

the maneuver umpire.Continue, please.As the chase helicopter approached, the 0-1

MARCH 964

Ilpparently took evasive action by executing a~ t e e p , 75-80 hank turn of approximately 120 to

k rd the flight of helicopters. At this point, the_ -bank attitude was shallowed to approximately and a steep climb started. The aircraft continuedthe steep climb, terminating in an inverted attitude from which it plunged into the trees, crashed,and burned. The overall maneuver is best described as an oblique loop.

How many witnesses were interrogated by theboard?

The board took statements from six witnesses,most of whom were Army Aviators.

Did these witness accounts give substantiallythe same description that you have just given us?

They did.What were the cause factors for this accident

as found by the board?The board found three cause factors. Theywere:1. While engaged in evasive action involving

steep turns and steep climbing turns, the pilot maneuvered the aircraft into an inverted flight attitude from which there was not enough altitudeto recover.2. The pilot exercsied poor judgment in attempting these maneuvers, considering the factorsof altitude, proximity of other aircraft, and thelack of necessity for the maneuvers performed.

3. The pilot's overconfidence in his ability contributed to his disregard for the dangers inherentin the type maneuvers attempted. t was the opinion of the board that the pilot's limited experiencecontributed to his attitude of overconfidence.

And what were your recommendations to preven recurrence?

The cause factors found are within the area ofself-discipline, maturity, and judgment. Thesetraits are acquired through a learning process,part of which combines experience and effectivesupervision. t was recommended that there be acontinuous program for making pilots aware oftheir individual limitations and those of their aircraft. t was further recommended by the flightsurgeon that pilots who, their associates believe,fly in an unsafe manner be relieved from flyingduties until they revert to a proper state of mind,compatible with safe operation of their aircraft.

Was there evidence that this pilot had exhibited signs of overconfidence in the past?There was. The board took statements from

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two of his fellow aviators w hich clearly indicatedthis trait.

Would you tell us what these aviators said?"Objection Your honor, this does not constitutebest evidence. These witnesses are on hand. f thepeople wish to record their testimony, we shouldhear it firsthand.

Objection sustained.Very well, your honor. The people are finished

with this witness.Does the defense wish to question this wit

ness?The defense has one question, your honor. Mr.

Recorder, will you please tell us how many hoursof flying experience this pilot had?The pilot had a total of 417 hours, of which 245

hours were flown as a student pilot, 23 hours ascopilot, and 149 hours as first pilot."The people will call their next witness.The people call Captain Fellowpilot.Captain Fellowpilot will take the stand.Captain, how well did you know the deceased

pilot?I was assigned to the same unit and had flown

with him on several occasions."Will you please tell us what you know about

the deceased pilot's flying habits?In my opinion, his ability as a pilot was above

average for his experience level. However, afterflying with him, I formed the opinion that he wasoverconfident. During one flight, he stated thatthere was nothing he could not do with an 0-1aircraft.

Can you give us specific instances which ledyou to this conclusion?

He once asked me to fly with him as an ob-server for a radio relay mission. During this flight,he simulated strafing troops, engaged in mockaerial gun fights with two Army helicopters, andflew at extremely low level over a city. Twiceduring this flight I cautioned him about makingsteep turns at treetop level, with no effect.At the conclusion of this flight, he laughinglyasked if he had frightened me. I told him that Ithought the maneuvers he performed were ill advised since they were not required to accomplishthe mission and were dangerous at such low alti-tudes. He answered by saying that no one evergets hurt in an O-lA.

'No one ever gets hurt in an O-lA.' Werethose his exact words?

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"They were.""Your witness.""No questions.""The people call Lieutenant Sameunit.""Lieutenant Sameunit take the stand.""Lieutenant, will you give us your opinion of

the deceased pilot's attitude toward flying?"In my opinion, he was overconfident in his

ability to the point of being dangerous . He toldme several times that he practiced prohibited maneuvers such as loops and rolls. During this fieldexercise, he made several landings at night into ashort unlit field with tall barriers at both ends. Noother pilot in our section considered this field safeat night. I believe his words and actions clearlydemonstra e overconfidence.

"Your witness.""Lieutenant, you said this pilot made several

landings at night on the field you and the otherpilots considered unsafe, did you not?""Yes.""Doesn't the very fact that he made these land

ings successfully prove that his judgment was correct?"

No, sir.""Why not? Could it be that you and the otherpilots were a little jealous of his superior fly-

ing ability? Were you scared of the field? Wereyou-

"Objection Your honor, defense is badgeringthe witness "

"Sustained. Counsel will ask one question at atime and permit the witness to answer."

"Very well, your honor. Now, Lieutenant, wereyou afraid to land in that field?

"At night, and without flares, yes."But this pilot was able to land successfully on

several occasions?""Yes.""And without damaging the aircraft?""Yes.""And with no apparent risk?""No ""No? Why not?""I saw two of those landings. The first time, he

brushed the trees, stalled, and dropped in hard.We all thought sure he'd bent the propeller. Thesecond time, he landed halfway down the fieldand had to ground-loop to keep from hitting thetrees at the other end."

"But he did make it in both times, did he not?"MARCH 964

"Yes.""No further questions.""Your honor, the people will now proceed to

the second accident. I call the recorder of the second accident investigation board to the stand."

~ T h e recorder will take the stand.""Captain, will you please describe the circum

stances surrounding the accident for which youwere the recorder of the investigation board?"

"May I use my notes?""Please do. We'd like to be accurate in every

respect.""At approximately 0900 hours, two 0-lA air

craft departed on a local VFR clearance. At approximately 1020 hours, these aircraft were landedat a civilian airport outside the local flying area.One of the pilots parked his aircraft and boardedthe other aircraft. This aircraft then began shooting touch and go landings. After the sixth takeoff,the pilot from the parked aircraft, who was ridingas a passenger in the rear seat, initiated a simulated forced landing. When the pilot in the frontseat applied power for a go-around, the engine didnot respond with full power. The aircraft toucheddown in a peapatch, went through a fence, andcame to r.est inverted, on top of another fence."

"No further questions.""Does the defense wish to question this wit

ness?""Yes, your honor. Captain, can you tell us what

effort was made to find the cause of engine malfunction?

"A check of the aircraft at the scene revealednothing. The oil screen was pulled and foundclean. The spark plugs were removed and foundclean. The fuel tanks both contained gasoline. Thefuel appeared to be clean and contained no water."

"What conclusion did you reach?""From witness statements, the board accepted

the fact that partial engine failure did occur, butcould find no cause."

"No further questions.""The people call Captain Throttleback to thestand."

"Captain Throttleback take the stand.""You were the pilot riding in the rear seat when

this accident happened, were you not?""I was.""Are you an instructor pilot?""I am not.""Yet you retarded the throttle to give the pilot


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Reliance on one navaid to back up a GCA can sometimesget your back in a crack.

US TH M ALLW HILE ON A routineflight in an OV-l Mohawk two Army Aviators hadan experience which could havecost their lives. In this day ofheavy traffic areas radar controland sophisticated air traffic control procedures safety duringinstrument flight is ensured toa maximum degree. Howevereven with the best instrumentation and radar available thingscan still go wrong.

The aircraft was returning toits home field which happens tobe close to a large Air ForceBase. The distance between thetwo fields is less than 3 miles.The Army airstrip has no instrument letdown facilities. As aconsequence the normal procedure for Army Aviators duringinstrument weather conditions isto make a low approach on instruments to the Air Force Baseand i ceilings and visibility permit continue on to the Armystrip for a landing under a controlled VFR clearance.

On the afternoon in question the weather was 1 500 feet broken 2 000 feet overcast visibility5 miles with scattered snowshowers. When the OV-l was 15minutes out from its home air-

Capt McCaskey is assignedto the Surveillance PlatoonUS R L viation BattalionAlaska.MARCH 1964

Captain Robert W. McCaskey

strip the pilot received notification from Approach Control thatthe weather at the Air ForceBase had lowered to 1 200 feetbroken 4 miles visibility withnumerous snow showers in allquadrants.

The pilot acknow edged theweather and requested a precision ground controlled approachto runway 9 with a controlledVFR waveoff to the Army strip.Approach Control granted therequest and communicationswere established with GCA.

ILS VOR LOMAF C5OV.1

After turning to a heading furnished by GCA the pilot wasinformed that he was in positiveradar identification with groundcontrol. The pilot at this timewas employing his number oneADF which was tuned to theouter marker at the Air ForceBase. The aircraft was sooncleared to descend to and maintain 1 500 feet the GCA glideslope intercept altitude.

Upon leveling off at this altitude the pilot found himself inthe midst of a heavy snowstorm.

D RADAR CONTACT TEMPORARILY LOST IN SNOW SHOWERD FINAL CONTROLLER TAKES OVER APPROACH.BOTH IC RE ON SAME HEADINGHE IS HANDED WRONG ICD BOTH IC DESCEND SIMULTANEOUSLYD BOTH IC BRE K LEFT SIMULTANEOUSLY

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GCA then furnished a headingwhich was to place the aircrafton a dogleg for the final approach to runway 9

The pilot continued his heading until directed to steer 0900 He was ,then notified that theaircraft was now on long final.The pilot noticed that his ADFneedle was pointing 90 0 to theright instead of off the nose ofthe aircraft, as it should have indicated for a normal approach.The pilot notified GCA of thisdiscrepancy and was informedthat he was still positively identified on radar and was oncourse. He continued with theapproach.At this point the GCA finalcontroller took over and told thepilot to begin his descent. Powerand props were adjusted, landinggear and flaps were lowered, andthe aircraft began its descentthrough one of the snow showers which surrounded the field.The words on course, onglide-slope, were reiterated sooften by the controller that thepilot felt greatly encouraged andenvisioned breaking out of thesnow clouds directly over thecenterline of the runway. Whenthe aircraft broke out of theclouds, however, the ground underneath looked completely unfamiliar to both the pilot andcopilot.

GCA continued to guide theaircraft in to the field, threemiles from touchdown; oncourse; on glide slope. Both aviators knew that something wasseriously wrong. The pilot notified GCA that he could not seethe airfield and that the approach did not look right. GCAtold the pilot very calmly thathe was on centerline and only 2miles from the runway. The pilot hopefully continued with theapproach.

The copilot was intently peering through the snow ahead of

4

the aircraft, hoping to get aglimpse of the airfield. At precisely the exact moment that theGCA controller said, On course,on glide slope; one-half milefrom end of runway, the copilot reached over and grabbedthe pilot's arm and pointed outin front of the aircraft. Directlyahead of the Mohawk was amountain which rose straight upinto the clouds and disappearedinto the snow.

The pilot simultaneously stoodthe aircraft on its wing andbanked to the left. He shoutedinto the microphone that he wasbreaking off his approach andwas turning to the left to avoidcollision with a mountain. Thepilot and copilot were both visibly shaken, but not half so muchas when GCA came back andanswered, Roger, Army ,we have you on radar in a hardleft turn over the field at thistime.

Both aviators were completelyflabbergasted. Negative, answered the pilot; we have norunway beneath us. . . . Amcontinuing on VFR.When GCA answered thatthey still had the Army aircrafton their scope, the pilot switchedfrequencies on his UHF radio toavoid saying something whichhe might be sorry for later. Thepilot and copilot maintainedVFR by remaining under theclouds and by circumnavigatingthe snow showers. They orientedthemselves and proceeded to notify the Army tower that theywere about 10 miles north andrequested clearance for an -mediate landing.

After having closed theirflight plan at the Army operations desk, the pilot picked upthe telephone and called RadarApproach Control, asking tospeak to the chief controller. Thepilot was told that RAPCON

U. S. ARMY AVIATION DIGEST


17/52

was aware of the problem en-countered. He was invited to theRAPCON office to see i f all thepertinent details could be so ar -ranged as to offer an explanationof what had happened.A thorough investigation in-cluded: tape recordings of all trans-missions between the GCA controllers and the pilot interviews with ATC per-sonnel and tower personnel, a grease pencil overlay ofthe radar scope with the courseflown by the aircraft which GCAvectored to the airfield markedon it.

The following conclusionswere drawn:

When the aircraft descendedto 1 500 feet and flew into theheavy snowstorm, GCA tempo-rarily lost contact. They saw anaircraft emerge on the other sideof the snow shower and TOOKFOR GRANTED that it was the

MARCH 1964

Army aircraft. Actually, it wasan Air Force C-54 on a VFRclearance. The pilot was in contact with the Air Force towerand was cleared by the tower tomake an approach to runway 9.The C-54 pilot elected to makean ILS. He was able to main-tain VFR by circumnavigatingthe snow shower activity.

While the GCA controller wasOBSERVING the C-54 make anILS approach, he was TRANS-MITTING INSTRUCTIONS tothe Army aircraft. The final controller was handed the WRONGAIRCRAFT to bring down theglide slope. When the C-54 ar -rived over the outer marker, thecontroller told the Anny pilot tobegin his letdown. Both aircraftwere letting down at the sametime.

When the Army aircraft brokeleft to avoid hitting the moun-tain the tower finally receivedword from RAPCON that an

Army Mohawk was on final un-der GCA control. Unable to locate the Army plane, the towerinstructed the C-54 to break offits approach and clear the pat-tern. The C-54 broke left overthe field and the GCA operatorobserving this maneuver on hisscope STILL THOUGHT HEHAD THE ARMY AIRCRAFTON RADAR IN A LEFT TURN.Both aircraft were once againexecuting the same maneuversimultaneously.

Radar observers and controllers are just as prone to erronce in a while as we are. t isup to us to help them avoid er-ror as much as possible. Theonly way we can be doubly cer-tain that our navigation or approach is correct is to use allfacilities we have available to assist us.

Unfortunately, in the caseabove the transponder in theAnny aircraft was inoperative.Had it been functioning properlythe near accident could possiblyhave been avoided. Runway 9 atthis particular Air Force Basehas four approaches: ADF,VOR ILS, and GCA. The pilothad 2 ADFs, one VOR and anILS with glide slope availablefor his use in the cockpit. Hadhe double checked his positionby tuning in his other naviga-tional aids he would haveknown that radar was in errorrather than suspect his ADF ashe did early in his approach.

The moral of the entire incident is very simple; it is verybasic; and it is very TRUE:radar and all the other advancednavigational aids we have available to us are NOT INFALLI-BLE WHEN USED ALONE.Utilize everything you have inthe cockpit to assist you in get-ting the aircraft safely on theground. You ll be a better pilotfor it and, who knows, you mayeven get to be an older pilot.

15


18/52

Ever hear of photic driving Wonder what happened to flicker vertigoaybe you can help solve the problem of

licker PhenomenaWAS ON A night VFR heli-copter flight at Fort Rucker,

Ala. One of the most severe elec-trical storms ever recorded inthis area was raising hob. Al-though the area in which I wasflying was clear for an approxi-mate 2 mile radius, I receivedthe full visual effect of the light-ning at my location. The flasheswere so brilliant that the rotorblades seemed to stop momen-tarily, and occasionally they ap-peared to turn in the opposite

16

Captain J C Rothwell

direction just like the stage-coach wheels in the westernmovies sometimes seem to do).I found this very distracting.Even though I am not instru-ment rated, I found myselfhaving to refer to instrumentsfrequently to prevent disorienta-tion.

Were these obviously errone-ous visual perceptions the effectsof a phenomenon known in thevernacular of aviators as flickervertigo? This is probably a mis

nomer as objective vertigo isdefined in medical dictionariesas a sensation that the externalworld is revolving around thesubject, and subjective vertigo isdefined as a sensation that thesubject is revolving or whirlingin space.

A rotary-wing aviator CaptRothwell is assigned to the U S.Army Aeromedical ResearchUnit Ft Rucker Ala.u S RMY AVIATION DIGEST


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During World War II, theNazis were well aware of the effects of the flicker phenomenon,which is more correctly identified as photic driving. They wereeven aware of the possibility ofemploying it tactically, as theyattempted to induce this reaction n allied night bomber pilots and crews by systematicallyinterrupting searchlight beamsat a frequency coinciding withthat of the alpha waves of thebrain. No report is available onwhether or not they were successful in thus disorienting alliedaviators.I t has long been reported inpsychological and psychiatric literature that a steady light flickerat a frequency of 4 to 2 cyclesper second can produce very extreme and unpleasant reactionsin normal subjects. These effectsvary all the way from extremeirritation to nausea, true vertigo,convulsions, and loss of consciousness.

The exact physiological mechanism behind this phenomenonis not clearly understood, butwhen light is interrupted orshadows are cast upon the human visual apparatus at a frequency which approximates thatof the alpha rhythm of the brain,and under certain environmental conditions, unfavorable reactions may occur. Susceptibilityto this reaction is increased bypilot fatigue, frustration, or amild degree of hypoxia. Thereare no warning signs; thereforethe onset may be abrupt.

t has been proposed that thisphotic driving condition may re sult when the rays of the setting

or rising) sun pass throughslowly revolving rotors, or propeller blades, to produce photicstimulation at 10-14 flickers persecond. In hypersensitive persons cerebral excitation, seizures, and unconsciousness co uldpossibly occur. However, whenan effort is made to substantiatethis hypothesis, documented

cases become difficult to find.Is photic driving flicker vertigo a problem in aviation? Is

the threat present, but in ordinary flying conditions an infrequent or inadequate stimulus?On the other hand, do welltrained pilots normally have lowsensitivity to this type of stimulus?

These are the types of questions that the U. S. Army Aeromedical Research Unit is interested in. Future researchprogram planning includes thestudy of this problem by meansof telemetered and/or airborneelectroencephalograms.Any subjective evaluations ofexperiences or difficulties associated with photic driving whichmight help to better define theexistence of a potential problemwould be appreciated. Pilots andunits in the field are requestedto send such information to theU. S. Army Aeromedical Research Unit, Fort Rucker, Ala.,36362.

HELP WW Gliders WantedWHO HAS A couple of CG-4Agliders? These were the onesused in the Normandy landings.Years ago the skies around FortBragg were full of gliders.

The museums at Wright Pat-

MARCH 964

terson AFB and Fort Braggwould each like to obtain a CG-4A glider for historical purposes.

Anyone knowing the locationof any surplus CG-4A gliders,please contact the

Office of InformationXVIII Airborne Corps, Fort

Bragg, N. C.Telephone: Fort Bragg 396-4111, extension 52245 or53237

7


20/52

xperiences o an ROT student flying

DON'T LAND short; thereare cows grazing in therUnover area, my flight instructor said as I went up forsome solo practice on short fieldlandings and takeoffs.

I'd completed 10 hours of the

8

I R I Follow Roads)Lieutenant Joseph B Swartz

ROTC flight instruction program at Middlebury College inVermont. One of the aims of theprogram, whereby the Armycontracts flight training for se-lected students, is motivationtowards an aviation career. I

was motivated all right anddamned nervous in anticipationof my first cross-country flight.

Middlebury College is a smallschool right on the edge of theGreen Mountains in Vermont.Middlebury's airport is a short

U. S. ARMY AVIATION DIGEST


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grass strip nestled against amountainside and completelysurrounded by maples and pines.This is where I had the privilegeof learning to fly.In my junior year in collegeabout 14 members of the advanced ROTC course applied forflight training. We signed agreements that i f we completed theprogram we would go for ArmyAviation training. We alsoagreed to serve on active dutyfor three years instead of theusual two years. We were givena battery of aptitude tests and athorough flight physical atROTC summer camp. When wereturned to school we foundthat only six of us had qualified.

We drew our flight suits andgot our flying assignments. I wasthe first one to go. I got to theairpoIi, met my flight instructor,and then met our Cessna 150.The first thing I learned washow to make a preflight inspec-tion. Then we took off andfound out what it was like to fly.

will never forget how my

Lt Swartz is assigned TDY tothe Dept o Advanced FixedWing Training USAAVNSprior to beginning flight train-ing.

MARCH 1964

stomach ended up in my mouthafter my first stall. I also willnever forget how I wonderedjust how we could ever find ourfield-and get the plane into itonce we found it. had been inthis area for four years, buteverything looked different fromthe air.

Our course included about 35hours of ground school and 35hours of flight. Ground schoolcovered weather, navigation andprinciples of flight. Our air workconsisted of landings takeoffsstalls and instruments. t wasparticularly interesting becausein Vermont in the winter everything tends to look the samewhite.

My first cross-country was co-incidental with the third snowfall of the year. The flight wasover the Green Mountains toLebanon, N. H. and back. I plot-ted the course the night beforeand had all my checkpoints setup. was going to fly east out ofMiddlebury at 5 000 feet to clearthe mountains, pick up Lebanonomni and slick right in. I got to2 500 feet and was bumping theciouds. My flight plan changedimmediately. decided to tryflying the passes. flew up route125 through Middlebury Gap toHancock, V t. Then had to find away up over the next line ofmountains. By the time didwasn t sure exactly where was.

picked an estimated headingand found Randolph, V t. FromRandolph it was a breeze to Lebanon.

On the way back decided toavoid as many mountains as pos-sible. I planned to go down theConnecticut River, then up theWhite River to Bethel, up route100 to Hancock, and then try toget back over the gap. finallyfound 125 and started up. For along while was sure the cloudswould close in before got over.t was a strange sensation to

look up and see mountains aboveme on both sides. The turbulencecaused by the mountains at thatlow altitude was kicking me allaround. Finally hit the Middlebury ski area with a couplehundred feet to spare and Iknew I d made it. I was onehappy student when finally gotback on the ground.

What good does the ROTCFlight Program do?feel it improved my motivation to fly. I d always wanted tofly but until actually did itwas worried that I couldn t do it.t also increased my desire tofly.

The ROTC Flight Programalso provides the Army with arelatively cheap method ofscreening some of its future pilots. t is able to determine forboth the Army and the individual i he has the ability to fly. Italso helps the man decidewhether he likes flying or not.

think it is significant thatthe number of ROTC flightgraduates who fail to completethe basic fixed wing course atFort Rucker is practically nil. Ifeel that no one can debate thevalue of the Army flight program to either the Army or theindividual.

19


22/52

PILOT OPER TIONThe thrust vector of V/STOLlift/thrust engines requires care

ful control both on takeoff andlanding because any overvectoring will give too little lift. Onesystem in Europe has controlledvectoring which automaticallygives the best angle of thrust fora given speed during transition,thus avoiding any possible overvectoring problems.

Whilst manual control of thethrust vector is obviously desir-

2

able, transitions carried out under all-weather conditions maywell lead to controlled vectoringonly practical tests will sup

ply the final answer. With anaircraft like the Balzac, whichhas a composite powerplant,enough lift is supplied by a bankof lift jets to give the pilot a verysimple action for takeoff.

He can select maximum poweron the propulsion engine andliftjets together, and the aircraftwill take its own flight pathwhich will be a combined vector

V STOLFrom a paper y R W Ha

of lift and propulsion. The pilotis not required to use his judgment during transition andwhen the aircraft is wing bornehe shuts down the liftjets. Acombination of liftjets and propulsion engine thrust vectoringbrings in the control problemmentioned earlier, but to alesser degree.

f the mission requires thatthe aircraft is overloaded forVTO, a short ground roll is necessary to obtain some wing liftbefore selecting a given thrustvector to become airborne. Thetwin lift/thrust system suppliesa maximum horizontal thrustvector and maximum accelera-tion until the thrust is deflected.A composite powered aircraftweighing 20 ,000 lbs., with thetwo liftjets deflected 20 aft during the ground roll, has a totalhorizontal component of thrust

including the propulsion en-gine) slightly less than the twinlift/ thrust engines. However, thetwin lift/thrust engines will bewell throttled during the mis-sion with the resultant increasein fuel consumption, so the radius of action will be less thanthe composite aircraft.u S. ARMY AVIATION DIGEST


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New aircraft create problems requiring new solutions. The V/STOL aircraft now in flight test or onthe drawing boards stir the imagination with their up and out capabilities. However, the questionsposed by the demands on pilot technique, ground impingement and all-weather operations need imaginative answers.

perationsA. J. Heyworth D.F.e. A.F.R.Ae.S.

\ 111111/1111,::

THE TRANSITIONt is estimated that with a

composite powerplant the timespent during transition from jetborne to wing borne flight andvice versa will not exceed twominutes total. The takeoff willbe completed in less than 30 sec-onds from lift et start to shutdown in flight; the landing transition will take longer.

The lift ets are started bybleeding air from the propulsionengine before takeoff. In flightprior to landing intake and exhaust doors are opened and theliftjets rotated at windmill speedby ram air permitting a normalair start to be carried out.

With the lift/thrust enginesthere is a point in favour of controlling the rate of change of the

MARCH 1964

thrust vectoring during takeoffthus reducing the time spentduring transition. This wouldalso prevent the pilot from overvectoring thereby reducing thejetlift component before there isenough wing lift. This techniqueis used by one type of aircraftflying in Europe and may be es-sential for an all-weather takeoff.ALL-WEATHER OPERATION

In many parts of the worldespecially Europe a VTOLArmy aircraft would be able tooperate under conditions of nilvisibility and with ice or snowon the ground. All-weathercapability is one of the greatestassets offered by a VTOL aircraft to the operators.

f some form of beacon or radar beam is set up to give avertical or very steep approachpath the pilot can lock onto thisand carry out an instrument letdown from say 5 or 100 feetdepending on the surroundingterrain.A rig was designed to proveautomatic height control in or der to reduce the time spent jetborne prior to landing. This rigconsisted of a liftjet suitablymounted to run up and down agreasy pole with a minimum offriction. A radio altimeter wasfixed to the liftjet. Height aboveground could be selected from30 feet to 5 feet whereupon therig descended rapidly and settledto the preselected altitude.

EROSIONThe amount of jet erosion

depends on the velocity of theair and the diameter and heightabove ground of the final nozzle.

Provided the ground is not toosoft for the aircraft to roll erosion is avoided by adopting arolling takeoff technique. Witha twin lift/thrust system theengines are run at maximumpower with the nozzles pointingrearwards; soon after the roll iscommenced the thrust is deflected and the aircraft risesimmediately. Similarly with acomposite powerplant the lift/cruise engine is increased tomaximum power and when theaircraft commences to roll the

Mr. Harker is Advisor to theChief Executive on Military Operations, and Mr. Heyworth isManager, Engineering Operations, for Rolls-Royce Ltd London, England.

21


24/52

liftjet power is increased rapidly.Due to the rapid thrust responseof the liftjets, maximum thrustis obtained in 1/2 second. Bothtypes of powerplant can use arolling takeoff to avoid erosion.

There are various ways ofprotecting soft surfaces to enablea zero length takeoff (ZLTO)to be carried out by an aircraftwith either the lift/thrustpowerplant or the compositepowerplant. Light aluminumplates can be pegged in theground and used several times;hardboard can be used for oneor two takeoffs; but tests with athin canvas tarpaulin have notbeen satisfactory. There is a considerable body of opinion thatground maneuverability is essential for combat aircraft landing in forward positions, andsome form of matting will benecessary to prevent the wheelssinking in soft ground, so thissame material could be madesuitable for ZLTO.

Further work has been donein the United States using aliquid spray to bond loose sandor soil as it sets, and a considerable amount of work is going onelsewhere on erosion. The bestsolution will be confirmed whena VTOL aircraft commences operational trials.

There is no reason why anormal concrete runway shouldnot be used for ZLTO or VTOL.There may be slight flaking ofthe surface but it is very smalland not enough to be a hazard.Hot gas ingestion is allied toerosion and once again the easysolution is a rolling takeoff. I fVTO is required, the aircraftmust rise and move away fromthe ground as quickly as possible. This is particularly necessary for the lift/thrust enginesbecause as the hot gas moves

outwards it can be sucked intothe forward facing intake. Liftjets with the intake on top of thefuselage will also experience asmall rise in air intake temperature bu only after prolongedground running before liftoff.

The pattern of the gas flowduring initial liftoff shows thatthe gases spread out rapidly forabout 70 feet but remain nearthe ground. Some 10 feet fromthe nozzle axis the cloud is only2 feet high. When the gases losetheir dynamic head they beginto rise, forming a saucer shape.By this time the aircraft willhave completed the liftoff andwill be well clear of the hot gascloud. However, if prolongedhovering is carried out overdust, sand or mown grass, theaircraft would be enveloped;mown grass in particular wouldfill the intakes of the lift/thrustengines or the composite powerplant intakes.THRUST DEFLECTION NDT KEOFFS

An indication of the effect ofjet deflection on the aircrafttakeoff distance is shown in theillustration. The dotted curveshows a conventional transportaircraft with the ability to carrya given payload over a fixedstage length. The only way toimprove its takeoff performanceis to increase the wing area andto install more power. As can beseen this approach on its owncannot be carried very far without producing an uneconomically heavy aircraft. A furtherimprovement in takeoff performance can be made with theaddition of high lift devices tothe wing and this can again beimproved with the provision offlap blowing air tapped from theengines. Finally in addition to

~ E F L E C T E O J TS- ; - - - F LAP BLOWING\ \ . - t - H IGH LIfT DESIGN\ \ \ ~ C O N V E N T I O N L DESIGN\ \IRCR fT ~ 'WEIGHT - ~ '0._.

T KEOff DIST NCE

the above, the propulsive jetscan be deflected to give a liftcomponent and this will havethe effect of further 20 % reduction in takeoff distance.

Full variahIe jet deflectioncan be accomplished in a number of different ways. One wayis to design a trouser piece exhaust system and duct the gas totwo propulsion elbows whichcan be rotated through 1800 Avariation of this system applicable to bypass engines is to ductthe bypass air and turbine exhaust gas separately to swivelling elbows as in the wellknown Bristol-Siddeley Pegasusdesign.

A further method; based onthe Rolls-Royce thrust reverser,is the switch-in deflector ordiverter. The thrust switchingdevice consists of a pair of clamshell doors or eyelids whichnormally form part of the jetpipe inner wall. When deflectedthrust is required, the eyelidsare swung rearwards to blankoff the propulsion nozzle, at thesame time uncovering an aperture at each side of the jet pipe.Extending from each aperture isa very short duct leading to acircular assembly of deflectingvanes called a cascade nozzle.The two cascade nozzles aremounted on large bearings andcan be rotated under control ofthe pilot. The geometry of thistype of deflector will give a deflection angle which is continu-

u. S. RMY VI TION DIGEST


25/52

ously variable from full propulsion through lift to full reverse.

There are several importantadvantages of the switch-in deflector. t has excellent performance characteristics. At cruisethe internal losses are extremelylow since the deflector vanes areswitched out allowing uninterrupted passage of the exhaustgas to a conventional highefficiency nozzle. The improvement in cruising specific fuelconsumption over a deflectorsystem having the mixed jet dis-charged through two rotatingelbows would be about 4. Inaddition, the switch-in deflectortakes advantage of the gain inspecific fuel consumption ob-tained from mixing the hot andcold exhaust streams beforedischarging them through acommon nozzle.A feature of using a separateconventional nozzle for cruiseand cascade nozzles for takeoffand landing is that the cascadearea can be chosen to give theoptimum engine working pointfor maximum thrust during thelifting phase, especially whenbleed air is required for flap

MARCH 1964

blowing, and the plain nozzlearea can be chosen to providethe lowest altitude cruise fuelconsumption.

In the combat area where theaircraft is liable to damage byenemy action, no hazardous condition can arise due to damageto the cascades as the aircraftcan continue and return to landat its base using the conventional nozzles. Also the lowintensity of infrared radiationdue to mixing the bypass andturbine exhaust gases substantially reduces the risk of unwelcome contact with antiaircraftmissiles fitted with infraredhoming devices.

t is worth stressing the advantages the switch-in deflectorenjoys in terms of life andreHability, because the design isbased on existing thrust re verser principles. Hundreds ofthousands of hours of successfuloperation have led to thrust reverser units reaching overhaullives in excess of 4,000 hours.A most significant feature thatthe switch-in deflector has incommon wi h the thrust reverser is that operation of the

eyelids presents no critical sealing problems. On the other handsystems based on the swivellingelbow have to operate with alarge and critical circumferentialgas seal.A major point affecting lifeand reliability is that the cascade assembly on the switch-indeflector passes the relativelylow temperature mixed gas flowand is only in operation forextremely short periods duringeach flight.

The question of which powerplant system is best for the newV /STOL aircraft DIGEST, Dec1963) has not been determined,and all the problems relating topilot operations, all-weathercapabilities, and ground operations remain unsolved. Howeverit is logical to assume, primarilyfrom pilot safety considerations,that V/STOL aircraft will havemultiple powerplants. The mostimportant consideration now isthat progress reports coveringall facets of V / STO aircraftprograms continue to be freelyaccessible to all parties concerned with their development.

3


26/52

ITHESHOE

W E VE ALL SEEN cartoons of women shopping for shoes. They sit feet extended,while exhausted clerks scramble through littersof boxes, tissue and discarded samples. Only afterthey ve tried on dozens of styles and colors dothey select a pair of size five needle-nosed pumpsand squirm and shove to get their size seven feetinto them. Aching like mad, they mince away,happily convinced their appearance is all thatmatters.

Some of us shop for safety the same way thesewomen shop for shoes. We keep trying on safetyprograms until we find something that looks good.Then we buy it with little thought for whetherit fits or pinches our aviation operations.

Like the ladies we wear our safety with greatpride while anyone is watching. But let us get inthe privacy of our own bailiwicks and off comethe shoes and safety. We wiggle our toes and

Col Hamilton is Director United States rmyBoard for viation ccident Research.

PIN HESColonel Robert M Hamilton


27/52

heave great sighs of relief. Now we can operateWhy does a safety program pinch? It pinches

because we substitute don't when we can't answer how? It pinches any time there are unnecessary restrictions.

It pinches because we often find ourselves inthe same rut that automotive safety has been insince we started paving roads. Let a holiday weekend come along and the news services are filledwith predictions of doom. They teU us how manywill be killed and maimed. They do their best toscare us into staying home and i f that fails theytell us to "Drive Safe " Not how to drive safe but"Drive Safe " In the meantime, we go on building100 mile-an-hour cars for 60 mile-an-hour roadsand 40 mile-an-hour drivers.

Negative safety has never worked for cars andit damned sure won't hack it for aircraft. I defyanyone to show me how wearing a set of don'tscan prevent accidents and still let milit ry avia-tion do its job.We can't afford to let ourselves be scared bynegative safety into staying on the ground. Wecan't afford to restrict our operations in any way.We need a positive safety program that fi ts-aprogram that will extend our operational capabilities.

We need to examine our equipment. Does itoperate like it's supposed to? Is it reliable? Doesit place the least possible demands on our crews?f we get a "no" answer, we ~ e e to show how

and why and get the equipment changed.We need to examine our training. Are we train

ing our crews to do every part of every job theway it should be done? Are we standardized? fwe're not let's find out why and make changes.

We need to examine our operations. Are wedoing everything the way we should? Here again,are we standardized? f not let's do somethingabout it.

We need to examine our facilities-our controltowers, weather services approaches, runways,taxiways, and the hundreds of other items thatplaya part in positive aviation safety.

We need continuing surveys of our equipment,our people and our facilities. When we get these,and when we get immediate corrective actionwe'll have positive safety.Right now is a good time to check for signs ofcorns and bunions. f your safety program pinchesyour operations in any way, then you've boughtthe wrong program. It's time to get rid of it andstep into some sure-fit seven-league boots with apositive approach to safety.


28/52

Kitchen Testing rmI N A FIERCE, competitivescramble, advertisers go allout to attract the potential consumer (and his paycheck). Eachproduct is kitchen tested, unconditionally guaranteed, roadtested over 100 000 miles andavidly used by a sports hero ofyour choice.

Where does it all end? Withthe consumer, who having a requirement for the product (or sohe's led to believe), buys thegadget that is thoroughly testedand guaranteed to do the bestjob.

The Army is also a consumer,seeking the best equipmentavailable to accomplish its mission. The test kitchen foraviation is the U. S. Army Aviation Test Board, which ischarged with ensuring thatArmy Aviators fly the bestequipment above the best.

The Aviation Test Board, formerly called the Army AviationBoard, was established at FortRucker, Ala. in August 1955.As Army Aviation has grown insize and importance, the Aviation Test Board has expanded incapability and contribution.

With the reorganization of theArmy in 1962 the Board wasplaced under the jurisdiction ofthe U. S. Army Test and Evaluation Command, Aberdeen Proving Ground, Md. Concurrently,

Capt Treacy is Public Infor-mation Officer U S. Army Avi-ation Test Board Ft RuckerAla

6

two other test activities at FortRucker were placed under theAviation Test Board. Theseactivities were the U. S. ArmyTransportation Aircraft Testand Support Activity (TATSA)and the U. S. Army Signal Aviation Test and Support Activity(SATSA).

Each of these support activities was established in 1956 by

Captain John T Treacy

its respective technical service. J i I I I I ~ ~

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Army Aviation Digest - Mar 1964

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