Army Aviation Digest - Mar 1973

8/12/2019 Army Aviation Digest - Mar 1973

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USAARLSCI SUPPORT CENTER

P.O. BOX 620577FORT RUCKER AL 36362 01.77MARcH 97GEST

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UNITED

DIRECTOR OF ARMY AVIATION, ACSFORDEPARTMENT OF THE ARMYBG William J. Maddox Jr .

COMMANDANT, U. S. ARMY AVIATIONSCHOOL

MG Allen M. Burdett Jr .

ASST COMDT, U. S. ARMY AVIATIONSCHOOL

COL Earl .W. Fletcher

EDITOR, U. S. ARMY AVIATION DIGESTRichard K. Tierney

ABOUT THE COVERThe UH 1 on the cover was edj_torially placed so that it wouldappear to be flying in a somewhat abnormal attitude. Such at titudes often are caused by poorattitudes among people. CW3Stanley Whitman considers attitudes on page 19, and on page 38SFC Bill Bailey discusses poor -attitudes found during a visit to anaviation unit

RMY VI TION

1GES2 MARCH 1973 VOLUME 19 NUM

Views From ReadersNightmare, LTC Norman E. ScottHey Tower Haven't You Got My Clearance Yet?

COL Robert E. Darlington, USAFAeromedic, LTC Nicholas E. Barreca, M.D.Charlie And Danny's Write-InTrue Or False? CPT James W. Isbell Jr .Attitude Attitude Attitude, CW3 Stanley E. WhitmanA Hole In The Floor, CW3 Dwayne L. PetersenAsbestos-Suited Medics Practice Aircraft Rescue,

SP4 James EakinsWriting For The DIGESTWrite To RightWarning SignsFull-Stall Landings Are FoolishLet's Stop Building MountainsPearl'sSystem Safety In Army Aviation: A Coming Of AgeNeed For A Small Fireflghting Vehicle USAASO Sez Insid

The mission of the U. S. ARMY AVIATION DIGEST II to provide information of an otional or functional nature concerning safety and aircraft accident prevention, tramaintenance, operations, research and development, aviation medicine, and othlated data.The DIGEST is an official Department of the Army periodical publilhed monthlythe supervision of the Commandant, U. S. Army Aviation School. Viewl exprel led hare not necessarily those of D.epartment of the Army or the U. S. Army Aviation SPhotos are U. S. Army unless otherwise specified. Material may be reprinted procredit is given to the DIGEST and to the author, unless otherwise indicated.Articles, photos, and iteml of interest on Army aviation are invited. Direct commtion is authorized to: Editor, U. S. Army Aviation Digest, Fort Rucker, AL 36360.This publication has been approved by Headquarters Department of the ArmSeptember 1972.Active Army units receive distribution under the pinpoint distribution system aslined in AR 310-1. Complete DA Form 12-4 and send directly to CO, AG Publlcationlter, 2800 Eastern Boulevard, Baltimore, MD 21220. For any change in distribution reqments, Initiate a revised DA Form 12-4.National Guard and Army Reserve units under pinpoint distribution allo Ihould sDA Form 12-4. Other National Guard units should submit requestl through theiradiutants general.Those not eligible for official distribution or who desire personal copies of the Dcan order the magazine from the Superintendent of Documents, U. S. Government PrOffice, Washington, D. C. 20402. Annual subscription ratel are $8.00 domeltic and $overseal. Single copies are 75 cents each.


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VR

JEWSROE DERS

Sir:We are limited here in Germany on

VOT stations. I was informed that it isnot correct to use the test position ofthe VORs in the aircraft for this purpose. Is it in fact wrong to use the VORtest position for checking the VOR? fit is then why do we have them?Please clear this up for me.CW3 Archee HarrellD Trp , 3rd Sqdn, 8th CavAPO New York 09185 The FAA states that the use of thetest position of the AN ARN 82 does

The following reVlSlons failed to beincorporated into the February 1973Maintenance Matters :

Rigging Of The Tail Rotor: The chainand sprocket are no longer changed asa matched set. Replacement of thechain and sprocket is necessary only ifit fails the inspection procedure outlinedin paragraph 9-15.g.(3), change 2, TM55-1520-210-20 , dated 29 March 1972.Change 2 deleted the NOTE which required that chain and sprocket shouldbe replaced as matched sets.Battery Relay: The fast, easy methoddescribed to determine if the batteryrelay is the cause of complete electricalfailure is incorrect. The transmission oillevel light is independent of the batteryrelay. Refer to figure 13-19, TM 55-1520-210-20, page 13-91. In the forwardbattery system, the jumper wire P24B 18 ,between contact points A2 and Xl, andMARCH 1973

not meet the intent of FAR 91-25. Furthermore , the radiated signal must becontrolled by the FAA.

The U S. Army Electronics Command states that the purpose of the testposition is to check for malfunctionsin the course indicator, the 30 Hertzamplifier, and the phase comparatorcircuits.Sir:

The article Autorotations-Cause &Effect by H. E. Roland, Jr., which ap-

the jumper wire P44B20, between contact points A 1 and X 1 of the aft batterysystem, provide this independence fromeither battery relay. There may beenough residual voltage in the batteryto illuminate the transmission light butnot enough to close the battery relay .Start Fuel Solenoid: When removing thestart fuel solenoid valve assembly, besure all electrical power is disconnected.The correct reference is paragraph 5-15,TM 55-2840-229-24, dated 23 April1971.UH-l Battery Voltmeter Circuit Breakers: When installing a battery at eitherthe front or rear location , the voltmetercircuit breakers at the opposi te locationshould not be opened. The referenceshould read TM 55 1520 210 20 (not-10).U-21 Temperature Control CircuitBreaker: When maintenance is being

opeared in the October 1967 issue ofAVIATION DIGEST, has considerable significance for the Canadian Forces. Iwould appreciate your assistance insecuring from the author permission toreprint the article in Canadian ForcesFLIGHT COMMENT.

CPT P. J. BarrettNational Defense HeadquartersOttawa,OntKIA OK2 The DIGEST is happy to grant permission for you to reprint Mr. Roland'sfine article.

performed on the U-21 that requireselectrical power, the temperature control circuit breaker is frequently pulled .This circuit breaker control the combustion air blower which is designed tohelp keep the avionic compartmentcool. f any of the avionics equipmentis turned on, this breake r should notbe pulled so as to prevent erious damage to the avionics equipment due tooverheating. (Reference TM 55-1510-209 10 / 1 page 6-1 , paragraph 6-6.) Thefollowing related information shouldhave been included: In addition, theventilation blower circuit breaker shouldbe closed . This blower will automatically operate when the temperaturereaches 49 degrees C in the avionicscompartment while the aircraft is onthe ground and power is on. (ReferenceTM 55-1510-209-10/ 1 paragraph 6-7.)Neither of the above circuit breakersshould be pulled when avionics equipment is on.


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8HTMARELieutenant olonel Norman E Scott


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t had to be a bad dream - a nightmare but Icouldn't seem to wake up He was going to take meon a guided tour

own here we maintain files onthose who h ~ e or will h ~ e...accidents

I N THE FIRST chamber theyhad what I believed to be miniature replicas of Army aviation accidents. ot all, understand, justan example of each only theyweren't miniature replicas theywere miniaturized To my horror,the real remains of past accidents.I knew then it had to be a nightmare, because I had just remembered seeing that flick based onDickens' story of ghosts of Christ-


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mas past and Scrooge and TinyTim.Now, getting the little mirror outI've checked those sore places onmy leg and rear portions. I remem-

ber sayi lg pretty frequently last to put lower wattage bulbs here inight, "Pinch me--I m dreaming?" the bath tomorrow starkSomehow . I wasn't dreaming white very bad for the eyesI really saw those miniaturized Damnit, that was some party . . accident scenes (Must remember my eyes are playing tricks on m

.. this though not n early one is n example from 1963, ofthe x t n s i ~ use of helicopters in the place known as SEA

you know the story ...three crewmen

4


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: I

Hey Tower ...Haven t You Got y Clearance Yet?

Colonel Robert E. Darlington, US FHq TAC/SE

There seems to be a natural law which demands that the growth ofair traffic shall always outspace the supply of modern equipmentand controllers. The best thing a pilot can do is to help ease theadverse situation with some plain everyday old-fashioned radiodiscipline-well tempered with courtesy, consideration and composure

. I 111 1I III/I III II . 1 1 11 I1 /1 / " " / I " " " ~ ; 1 . . i l . ~ /. . c l l : . l ~


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N OT TOO MANY years ago,there were a few outfits whichrequired a cross-training programfor air traffic controllers and aviators. The idea was to strap ayoung tower or GCA controllerinto the back seat of a jet and lethim enjoy the thrill of a dwindlingfuel supply while trying to workinto the landing sequence. Thepilots, on the other hand, wererequired to visit tower, GCA orRAPCON on a recurring basis sothey could see how much fun itwas to handle a mix of fast airplanes, slow airplanes, IFR trafficand VFR traffic with only one ortwo runways to play with and noless than a million people talkingat the same time.

The result of the program wasa healthy respect for the otherfellow's problems. Unfortunately,the decrease in available cockpit/flying hours and the increase inrecurring ground training dutiesmake it tough to keep that kind ofprogram alive.But the need for mutual respectwithin the air traffic control aviatorteam, however, hasn't decreasedat all.There seems to be a natural lawwhich demands that the growth of

air traffic shall always outpacethe supply of modern equipmentand experienced controllers. Giventhis fact, the best thing the pilotcan do is to help ease the situation with some plain, old-fashionedradio discipline-well temperedwith courtesy, consideration andcomposure.

When I hear a pilot arguingwith an air traffic controller, italways prints out in my mind sadolescent aviator. f an airbornepilot has a valid reason for not accepting a clearance or lack of same,there are procedures, such as declaring an emergency, for seekingresolution.

f safety considerations are notMARCH 1973

involved, the only place to pursuean air traffic disagreement is ONTHE GROUND, not over theradio.

There are two major reasons forthis. First , the pilot is usually tunedin on only one frequency. Thus, hemay not have s great an awarenessof the total traffic situation as thecontroller who is listening in onUHF and VHF frequencies plus acouple of landlines. Lacking thisappreciation, the wrong chatter,argument or delay at the wrongtime could very well be puttinganother aviator in a bigger pinchthan the first pilot thinks he s in.

Secondly, if a situation is gettingso sporty that a crusty old aviatorof 5 or 6 (or more) years experience blows his cool with a blast at

the controller, consider this: f thepilot is that rattled, how will hisblast affect the rattle-factor of thefirst term controller who possesseslimited experience in aviation?Good radio discipline is not entirely a matter of composure andminimum verbiage. t also includes

waiting until you're sure the frequency is clear before transmittingafter a channel change, and it includes letting the arrival controllerknow your complete intentionswithout making him play "20Ouestions.

The courtesy and considerationpart of the formula doesn't necessarily pertain to the use of yes,sir, "thank you and goodevening. These are good phrases

Continued on page 9


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Tips To Healthful Living Part IThe Health Consequences

Of Smoking

lTC Nicholas E Barreca M D

Provided by the Society 1 U S. rmy Flight Surgeons

HOW INDIFFERENT we havebecome to the risks of thatfoul abuse of smoking. The smok-er fingers the often colorful andspellbinding commercial pages ofthe many popular news media,carefully overlooking and uncon-sciously denying the warning: TheSurgeon General Has DeterminedThat Cigarette Smoking Is Dan-gerous o Your Health He or shefleetingly, but nervously ascribessuch chance disaster to "them, notI, me or thee." t never happensto us, always them, certainly not8

now, perhaps conceivably, thoughremotely, in the distant future . . .when we certainly won't care. Orwill we?The smoker even turns to hisfellow man for security. He casu-ally, seldom apologetically pro-nounces, You don't mind if Ismoke?" And most of us blithely,yet witlessly respond, "Not at

a1l " or Go right ahead" or"Think nothing of it." Would ourreply be as spontaneous if thesame person announced, "Youdon't mind if I kill myself but

slowly?" or Do permit me to con-tinue in my personal contributionto research in cancer and heartdisease "Flight surgeons, being con-.cerned with health and fitness,have as their goal the reductionof both the immediate and long-term risks or consequences ofleven our seemingly most trivialbad health habits. As thoughtful,physicians, they are interested inextending our useful and vigorousexistence and maximizing our per-formance capabilities. However,

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their least satisfying experiencemust often be the treatment of disorders beyond the reach of presentday curative medicine . . . thoseconditions that are best prevented.

Today each of us, smokers andnonsmokers, can playa role in preventing serious disease and disability. The smoker can quit smoking. The nonsmoker can set theexample, particularly for theyouthful, developing minds of ouroffspring. Why quit or preventsmoking? Because there is incontrovertible evidence amassed thatimplicates smoking as a causativeor contributing factor in the development of serious, usually lifethreatening and often fatal disease.Diseases that strike just about thetime when most people need andappreciate healthful, comfortableliving most.

Just why is smoking so harm-ful? There are several reasons.First of all, smoke is irritating tothe tissues with which it comesinto contact. t ultimately causesdamage and deterioration of thesetissues. Then smoking permits thebloodstream to become partiallysaturated with carbon monoxide(CO). CO produces a form ofhypoxia, like being at 12,000 feetof altitude before leaving theground. This insult by itself or incombination with environmentalpollution may produce some ofthe systemic or distant effects ofsmoking. Finally, many of the par-ticulate and gaseous componentsof tobacco smoke will produce un-toward effects throughout the bodyby interference with the chemicalsystems or by chemical alterationof specific body tissues and surfaces. Look at the constituentsfound in tobacco smoke (see box,page 11). The first three arc likelyto be those that contribute to thehealth hazards of smoking., Thenext six (*) are thought to probably contribute to health hazards.The remainder of the list are on yMARCH 1973

suspected contributors. f someoneprepared you a drink with each ofthese foul constituents added before your very eyes, would youdrink such a poisonous cocktail

and drink it and drink it anddrink it twenty, thirty, forty timesa day? The sophisticated analystsamong you will say, But theseingredients are only present inmicrogram and milligram quantities. The human body functionsbiochemically on as little as amicro-microgram of matter, sometimes less. Do you not think thatmalfunction can occur any lesseasily? Why is smoking so potentially harmful to your health? Because its assault is invisible andinsidious . . . you can't see thename of your poison, it' s obscuredin smoke and haze.Let's take a look at some of themore serious health consequencesof smoking. Each is a seriousthreat in and of itself. Granted,each of us is somewhat resistantto some of these diseases becauseof our genetic inheritance. By thesame token, each of us is likely tobe susceptible to one or moregiven the right poison. The list ofconsequences (see back cover) islong enough that few of us are so

Rest in.plecessecurely)

,

well endowed that we can ignorethe threat from some of thesecorridors of suffering.CORON RY HE RT DIS-

EASE - Smoking is one of themajor risk factors contributing tothe development of coronary heartdisease (CHD) or hardening ofthe coronary arteries as manyrecognize it. Cigarette smokingcan act independently or together with other known risk factors in leading to heart attacks ormyocardial infarcts as your flightsurgeon might say. Autopsy studiesshow that cigarette smoking is alsoassociated with the increased development of arteriosclerosis ofthe aorta (hardening of the body's'Jargest artery). For people with already existing CHD, smoking leadsto the likelihood of more seriousdisease and increased complications. t also increases the chancesof death from these complications.Several U. S Presidents have survived heart attacks for more thana decade by careful, nonsmokingliving. Once a smoker stops smok'ing, the risk of death from CHD isdecreased. When one comparescigarette smokers with nonsmokers, the risk of developing CHD is2-3 times greater depending on the


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tumors always occur on the lowerlip (perhaps one should worshipother than the sun).THROAT CANCER - Cigarettesmoking is a significant factor inthe causation of cancer of the lar

ynx (vocal cords and voice box).Pipe and cigar smokers have aboutthe same risk, maybe slightlylower. Alcohol is a minor risk factor in the development of the disease. Think of those who use bothin excess.ESOPHAGEAL CANCERCigarette smoking is significantlyassociated with the development ofcancer of the esophagus (tubeleading to the stomach). This riskis as great for cigar and pipe smokers, perhaps slightly lower. Studieshave also shown a significant association between alcohol consumption and cancer of the esophagus.Further, the combination of exposures, smoking and alcohol, isassociated with especially highrates of this cancer.

BLADDER CANCER - Nameyour cancer, smokers. That's whatits getting to be the more medicalscience studies the associations ofdisease with smoking. There is asignificant association between theincidence of bladder carcinomaand cigarette smoking for both menand women. Bladder cancer is alsoassociated with certain occupations

in the aniline dye industry but theassociation with smoking is separate and distinct. This associationis not apparent for pipe and cigarsmokers. However, they aren'tcompletely off the hook. There isa correlation between the use ofchewing tobacco and cigar smoking with adenoma and adenocarcinoma of the kidney.PANCREATIC CANCERThere is a significant associationbetween cigarette smoking andcancer of the pancreas (the olebeef bread where insulin and digestive juices are produced andstored). This association applies toboth men and women.

ORAL DISEASE - A wholebarrel of minor irritations and disorder of the mouth are associatedwith smoking. Smoker's tongue isone of them. Certain dental problems are another. General oralhealth is simply much better amongnonsmokers.

ALLERGY - Tobacco smokecan contribute to discomfort inmany individuals, which is a complex of irritative and allergic responses. Exposure to tobacco mayproduce recurrences of allergicsymptoms in nonsmokers who suffer with allergies from diversecauses. How many non-asthmaticsmokers have from time to timeexperienced a sensation of wheez-

COMPOUNDS IN CIGARETTE SMOKECarbon MonoxideNicotineTar*Acrolein

*Cresol*Hydrocyanic Acid*Nitric Oxide*Nitrogen Dioxide*PhenolAcetaldehydeAcetoneAcetonitrileAcrylonitrileAmmoniaBenzene2,3-Butadione

MARCH 1973

ButylamineCarbon DioxideCrotononitrileDimethylamineDDTEndrinEthylamineFormaldehydeFurfuralHydrogen DisulphideHydroquinoneMethacroleinMethyl AlcoholMethylamineNickel CompoundsPyridine

ing or chest constriction? Tell thetruth now smokersTOBACCO BLINDNESSThere is a rare disorder known astobacco amblyopia, a blindnesswhich evidence suggests is relatedto the cyanide component of tobacco smoke when certain otherdeficiencies are operative.

AIR POLLUTION - Think ofthe smoke filled room of a cocktailparty. Recently a medical investigation showed that individualswith angina pectoris (chest painfrom CHD) had increased symptoms when they drove in urbantraffic due to carbon monoxide(CO) levels. Think of how suchindividuals might fare at a cocktailparty or in the smoky cabin of amodern jetliner. In these respectssmoking is merely inconsiderationand irresponsibility. The levels ofCO in smoke-filled rooms havebeen shown to equal and at timesexceed the occupational thresholdlimit valves that are applied industrially to determine safe limitsof exposure for a normal workday. The extent to which these exposures bear on general health orthe incidence of illnesses is presently indistinct.

INFANT DEAm - Very recently it has been established thatpregnant female smokers runnearly twice the risk of deliveringa low-birth weight child and run ahigher risk of stillbirth. This isespecially so if she smokes beyondthe fourth month of gestation.EXERCISE INTOLERANCE -Certainly of importance to the military is man's ability to performphysically. A review of a numberof fitness tests, comparing smokersand nonsmokers, indicates thatcigarette smoking impairs exerciseperformance for many types ofathletic events and activities involving many types of work capacities.Had enough? Are you convincedthat smoking is generally undesirable no matter how you look at it?


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How do you feel when you wakeup in the morning, if you wake up?Drugged? Mouth shaggy and foultasting? How's your concentrationwithout a cigarette in your hand?Ever spend an hour and one-halftrying to find or buy cigarettes?What about the mere compatibility of smoking with the aviation

e n ~ i r o n m e n t ? Not too long ago asenous study was completed to determine carbon monoxide (CO )levels on the flight decks of commercial aircraft. The concern wasfor the buildup of exhaust fumescontaining CO on taxiways whileaircraft await takeoff clearances.The results were borderline. Wouldthey have been so if the crew werepermitted to smoke? Several yearsago on the flight deck of a USAFC-141 this author observed six ofsix flight deck air crewmen smoking simultaneously. The weatherreport? . . . Obscured in fog andhaze in the cockpit.

Most heavy smokers can developCO levels in their bloodstreamsthat take up to 8 to 10 percent ofthe oxygen carrying capacity ofhemoglobin. This effect, independently and in combination withdecreasing barometric pressure,causes hypoxia. The most noticeable effect is diminished night vision a 25 percent decrease evenat sea level. Is vision important inaviation? Still airframe manufacturers install ashtrays in all militray aircraft.

What about the fire and explosion hazard? Refueling operations, fuel transfer . . . oxygensystems? Consider the jet jockeywho smokes in between breathsfrom his oxygen mask. It's possibleto survive such tom foolery butthe risk is high.

At least AR 95-1 has something to say about smoking: Smoking within 50 feet of anaircraft on the ground is prohibited. Smoking is prohibited in air-

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craft under the following conditions:a. During aU ground operationsb. During and immediatelyafter takeoffc. During fuel transfers operationsd. Immediately before andduring landinge. At any time an occupantdetects gas fumesf. When oxygen is being used

Not only is smoking incompatible with health and often life,it is incompatible with the flyingenvironment. So when are you going to quit smoking? Impossibleyou say? It's an addiction?Boulderdash and bull feathersSmoking is as much an addictionas you want to make it.

Some people advocate decreasing the number of cigarettessmoked, the length of cigarettessmoked, the depth of inhalation,the frequency of inhalation and thegaseous and particulate contaminants of smoke. The first four arelike eating one potato chip liketelling the gay lothario to stop atthe kiss of a hand. The last hasn'tbeen developed yet to the extentthat would be necessary . . . andwhen it is smokers probably won'tlike it anyway.The solution is to stop coldThrowaway the pack. But, andthat is an important but, you mustbe convinced that stopping isworthwhile before hand. How doesthat happen? Well, smoking mustbecome a personal problem foryou. Not a threat to your life necessarily, but a similar feeling. Thiswill only happen when you startlooking realistically at the effectsof smoking around you. The peoplesick and dying around you, yourown disability and the mountingevidence revealed above. Try running around the block just once. fyou feel like a 90-year-old, youhave the makings of a personal

problem. You should feel like manyof us remember 16.Think of your family, thosedependent upon you for support.It's unfair to your wife, your children and your grandchildren thatthey should be denied the pleasureof your vigorous and healthy attentions. Think of the generous retirement from the Army, the oneyou've always bragged about as afringe benefit. You have to be aliveand well to enjoy it. Finally, thinkof the peace of mind that will prevail when you quit smoking. Nolonger will there be a need to worryabout that pain or tightness inyour chest, that lump or hoarseness in your throat, that cough andphlegm, the shortness of breaththe terrible threat of cancer.

Do some people need help tostop smoking? Certainly To someextent all do. Smoking is a habitthat is encouraged by man's socialconvictions and engagement. t isnatural then to seek and ultilizesocial reenforcement to discouragesmoking. Make it a group affair.Find two or three others in yourpredicament. Quit together withmutual reenforcement, concern andencouragement.Some individuals may also respond to the help of physicians orpsychologists. Drugs may be usedin conjunction with various behavioral therapy. One way or theother find your way a discouragingor quitting this costly ugly, morbid, suicidal habituation. Let's faceit, "smoking stinks." The nexttime someone asks Do you mindif I smoke?", remember the re

~ e n t h u n t i ~ g TV melody and sing,Yes, I mmd very much if yousmoke yeh , yeh, yeh I mindvery much if you smoke ... yeh, yeh, yeh . . .I mind very much if you smoke . . . "HEAL TH CONSEQUENCES OF SMOKING,A Report of The Surgeon General: 1972,Department of Health, Education and

W e l ~ a r e Public Health Services, HealthServices and Mental Health Administration. Available for sale from the Superintendent of Documents, U. S. Government Printing Office, Washington, D. C.20402. Price 70, Stock No. 1723-005.

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ChfJrlie fJnd DfJnnY s Write Inear Danny: There were numerous cases of overheatedbatteries in UH-1 helicopters inour unit during hot weather, apparently caused by voltage regulators being set too high. Accordingto TM 55 1520-210-10, paragraph 3-21, step 10 and step 14,the voltage regulator should read:

Main generator 28 to 28.5 voltsand standby generator 27 to 27.5volts. TM 55-1520-210-10 statesthe main generator should be set tothe following values according tothe average ambient temperatures:27 volts 90 F (and above)27.5 volts 32F to 90 F28.8 volts 32F (and above)The standby generator voltageshould always be adjusted 1.0 voltbelow the main generator. What

should we do? Mr. I.A.B.

Danny's answer:' You have a problem and here ,is the answer.This information was obtainedfrom the U. S. Army ElectronicsCommand (ECOM) and;action hasbeen initiated to change themanuals accordingly.The information in TM 55-1520-210-20 should be the sameas shown in paragraph 3 4c of

TM 11-6140-203-15-2 as givenbelow:VOLTAGE REGULATOR:Check to see that the voltageregulating device' on the aircraft isset as shown in chart below. Theoptimum voltage setting for thevoltage regulator is determined by

MARCH 1973'

the voltage requirements of theassociated equipment, temperature,type of battery, frequency anddepth of discharges, and recharg-,ing rates. Undercharging will result in poor performance, whileovercharging and high temperatures may cause excessive gassing,spewage of the electrolyte, anddamage to the battery. Compensatefor temperature changes by checking the generator voltage regulatorsetting on the aircraft at least every25 flight-hours , or weekly (whichever occurs first). Use the chartbelow for adjusting the generatorvoltage regulator setting for varioustemperatures:

Ambient .ground level temperature (OF)Above 80Between 32 and 80 Less than 32V 1tage regulator setting (volts)Between 26.5 and 27.5Between 27.5 and 28.5Between 28.5 and 29.5

Dear Charlie: Our unit operatesand is responsible for the maintenance of two T-42s. Needless tosay, guidance in the form of TMsis sadly lacking at OUF level, specifically operator's manuals.The present operator's manual,TM 55-1510-208-10, appears tobe a rehash of the civilian versionand is sadly lacking in detail. Inaddition, it does not always agreewith the DA published checklist.T there any relief in sight forus poor lost souls out in the boonies ? ,

CW4C:B.F.

Charlie's answer: Have heart myfriends, relief to your problem ison the way.We are told that the U. S. ArmyAviation Systems Command ispresently compiling a DA approved operator's manual for theT -42, which we hope will be farsuperior to the present publication.At this time there has been nodefinite time table established forthis document to hit the newsstands

bu t be patient, it's on its way.

Dear Charlie: In reference to thetail rotor blade bearing of the OH58A, is this bearing prefabricatedon the tail rotor blade? TM 55-1520-228-34P shows that it is removable (page 236, item 11, figure65). TM 55-1520-228-20 does notshow or state the clearance or theproper maintenance measures thatshould be taken to correct it. Yourhelp will be greatly appreciated.SP4 J.T.

Charlie's answer: The SMR codelisted in TM 55-1520-228-34P forbearing PIN 2.06-010-765-1 isP F . This code indicates the subject bearing may be replaced atdirect support. TM 55-1520-228-35, the direct support, general support and depot maintenance manual, has complete instructions fortail rotor blade bearing replacements in chapter 8. TM 55-1520-228-20, the , organizational maintenance manual, contains onlythose instructions which are applicable to organizational maintenance.

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utorotational descent performance is afunction of indicated air speed nd is essentiallyunaffected by density altitude nd gross weight

rue or FalseThe author reviews, in a nontechnical manner some important factors about autoratations in order to giveoperational aviators more insight and knowledge ofwhat forces are at work during this emergency maneuver

AUTOROTATIONS are prob-ably the most controversialsubject discussed among rotarywing pilots. Their conversationsusually cover topics like glide distance, rates of descent, zero groundspeed touchdowns and the techniques to accomplish the maneuver.Most rotary wing pilots achievea high degree of stagefield pro-14

Captain James W Isbell Jr.

ficiency when it comes to autorotations. Peak proficiency is attainednormally about the time the aviator becomes an instructor pilot(IP), since the IP not only has tocope with the aircraft and otheroutside factors but also the pilothe is instructing. The odds arethough that most pilots feel trulycomfortable performing autorota-

tions after a few practice lapsaround the traffic pattern. Then ifthis is true, how do operationalpilots hope to have first-time success when an actual emergency occurs requiring an autorotation? Inmost instances there isn t muchpilots can do except mentally pre-pare themselves so that when thesudden rotor decay does occur,

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IIIIIIIIIII

NOTEThe material used to develop this article was taken from actual test dataand individual experiences may not be explained fully by what has beenpresented. References:

NAVAIR 0080T80 AH-1G Operator s Manual FFTS Tech Document Rpt No. 64-27 NH-l D/H Operator s ManualTest Pilots, Test Flight Center, Army Act.ivity, Edwards FB

L _they will have all the necessaryinformation at hand to make a cor-rect and safe decision.One obvious approach is tostudy the dash 10 and understandthe recommended .procedures.Since the dash 10 is broad in scopethis may not answer all your ques-tions. This is especially true whensome dash 10 statements seem tobe contradictory. For example,chapter 4 in a few rotary wing dashlOs states that autorotational per-formance is a function of indicatedair speed and is essentially unaf-fected by gross weight and densityaltitude'. On the surface this state-ment appears to be incorrect; if theaircraft weighs more it should falat a faster rate and not glide as far.To understand why the statementis in fact true, first the pilot needsto realize that both rotor rpm andcalibrated air speed are constants.To help the pilot understand whatis actually occurring during anautorotation, a little investigationinto the aerodynamics of an auto-rotation may help answer the ques-tion.Keep in mind that an autorota-tion is classified as an emergencymaneuver and it's not the intent ofthe author to dictate procedures orteach a course in aerodynamics,but rather to give the operationalpilot a little more insight andknowledge of what happens duringan autorotation.Blade Section ElementsVector Quantities)Figures 1 and 2 show typicalvector quantities of two rotor bladesection elements. f you were toview the regions from above aMARCH 1973

Figure 1Forces In The Propeller Region

Lift

Disc Plane DragD \o ve Vel.ocity\to nt .ee S u ~ ~ ~ __________ ________t

Velocity Due To Rotation + Flight Speed ComponentFigure 2

Forces In The Autorotion Region

iscResultantRelativevelOcity. .o.- ,

....,...--Acceleratin gForce

IIIII

Velocity

Velocity Due To Rotation + Flight Speed Component

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FigureForward Flight utorotation

Flight IDiredion

tall Reversed

rotating blade with forward airspeed, the autorotation and propeller regions would be similar tofigure 3 on page 14. The propellerregion provides the .majority of thelifting forces that retard excessiverates of descent during .autorotation. The autorotative region provides the driving forces needed tomaintain a desirable rpm. Angle ofattack and velocity due to rotation are the factors that allow arotary wing aircraft to autorotate.Due to the differences in velocitiesof air flowing over the blade, atwist is given to the rotor blade tohelp equalize lifting .forces. This.twist is also necessary for autorotation and accounts for the magni. ude of the forces acting on theblade during the autorotation.

The second and the most important factor governing autorotative performance is the relative

Flow

velocity of air that flows across therotor blade at various points alongthe blade. The velocity of air (orthe velocity of the blade due torotation) at .a point decreases asthat point is moved from the tip ofthe blade toward the hub. The inner 25 percent of the blade produces little lift and high drag thustending to slow up the blade. Inforward flight the -aerodynamicforce perpendicular to the axis ofrotation changes to thrust +) ordrag - ) at each 180 degrees ofrotation, thereby providing anautorotative force (thrust) and anantiautorotative force (drag). Rotorrpm stabilizes (zero net torque)when these two forces are equal:Assuming collective pitch remainsconstant, a greater angle of attackof the rotor disc increases rotorrpm, as during deceleration, whilea decrease in the angle of attack, asin descent, will reduce rotor rpm.

The resultant vectors are depictedin figures 1 and 2as lift vectors.Gross Weight ConsiderationIf figures 1, 2 and 3 are representative of an aircraft at somegross weight within the normalusage range of that aircraft, what

happens if a higher gross weight isused? An aircraft that weighs moreshould fall faster than the lighterone. This greater rate of descentchanges the angle and magnitudeof the input forces acting on therotor blade and correspondingchanges occur with the resultantlift forces.In the propeller region the upflow velocity due to the greaterrate of descent does not change theresultant lift forces significantly.(Check figure 1 and note the difference between upflow vector androtational vector.) As we move intoward the hub a different set ofinput forces are acting on the bladeand the corresponding resultantlift vector changes significantly tocause rotor rpm to increase. (Figure 2 - a change in upflow vectorwith reference to the rotation vector should have a significant effecton the lift vector.)This increase in rpm is the keyto the aforementioned statementconcerning autoFotational performance. Unlike our fixed wing counterparts who change forward velocity (indicated air speed) in aglide to compensate for a greatergross weight with the formula

~ : : rotary wing pilotscontrol rotor rpm to accomplisheSsentially the same thing by adjusting collective. The equilibriumfotor rpm is obtained when thedeceleration torque (drag) generated in the propeller regionexactly balances the acceleratingtorque (thrust) generated in theautorotative region, as discussedearlier. V 1 equals glide indicatedair speed for a gross weight W1 V2equals glide indicated air speed fora new gross weight W2

16 U S ARMY AVIATION DIGEST


19/52

As this rotor rpm is decreasedto safe limits by application of collective-pitch, the angle of attack ofthe entire rotor blade is changedand the dimensions of the propellerand autorotation regions correspondingly change. Figure 3 showsthose regions for some gross weightlighter than the gross weight ,thatcauses rotor overs peed. VVhen thecollective pitch is changed, thepropeller and autorotation regionschange. The autorotative region becomes smaller in diameter and thepropeller region , larger. Thischange not only increases lift forflight and decreases lift for drivingthe blade but also changes a thirdfactor, induced velocity.Induced velocity is derived fromair being deflected downward bythe airfoil and may be considered

as producing a force that helps retard descent. This force increasesas angle of attack is incre.ased.The summation of these forcesclosely approaches that of thelower gross weight aircraft and interms of glide distance and rate ofdescent tend to be almost the same .If the theoretical autorotation iscorrect, then the actual autorotation should closely correspond tothese results.Test Flight DataFigure 4 depicts test flight datathat verified the preceding discussion. The points plotted are resultsfrom closely and exactly monitoredautorotational performance. (Note:The plots for the curve are takenat different density altitudes.) Acurve is formed after the points areplotted and this curve is then usedto derive figure 5. Figure 5 is whatwe see in the dash 10 and isnormally accompanied with airspeeds and the rotor rpm to beused. (Note: Control of the rotorrpm is an important factor g o v e r ~ -ing autorotational performance.This factor becomes more evidentwhen air speed is compared to thevelocity of the blade due to rotation.)MARCH 1973

2800

2400c: 2000=-.. 1600-:GJul tGJ 1200c-GJ 800-D 400

o

Figure 4

:

f'7~ Ell~ _L-

~ ~'l:p- r'". lnl.. r Airlslpeed o r _

... [:l M a ~ i m u m I- ' - - - Glide Distan 'ce,/ I IAirspeed For MinimumR ~ t e ot' D ~ s c ~ n t

o 20 40 60 80 100 120True Airspeed-Knots

Figure 520- 18GJ1 ' 16..

0 1400- 12GJ'0 10;)- 8clGJ 6:;) 4tl tI 2D.

',,;f


20/52

To obtain minimum rate of descent certain parameters must besatisfied to obtain a lift versus dragrelationship to enable us to slowour descent as much as aerodynam-ically possible. This is, if the greatest amount of lift can be derivedwith the least amount of airfoildrag, then we should be able toslow our rate of descent to someminimum. During flight testingmany different rotor rpm's are triedand the most favorable rpm s pre-sented in the dash 10 chart.

Maximum glide distance sfound similarly; however, distancetraveled across the ground s a consideration and an air speed ischosen when the rate of descentand air speed attain the best ratiofor maximum glide (distance flownin a zero wind condition).

Now the statement Autorota-tion descent performance s a function of indicated air speed and sessentially unaffected by densityaltitude and gross weight" tendsto make sense. The two points toremember are: (1) "essentially"means that the difference under

normal flight envelope conditionsdoes not warrant a change in airspeed to offset density altitude orgross weight changes to attainmaximum glide; and (2) if param-eters are taken to extremes,changes in performance can be. expected; i.e., a very light aircraft at1,500 feet density altitude or maxgross aircraft at 13,000 feet (needoxygen there ).

Another controlling and important consideration during theautorotation is the air speed to beused. Minimum rate of descentautorotations are nice if our pro-ficiency is above average, but if welook at figure 4, we see that regard-less of the way we go an increaseor decrease of air speed always increases minimum rate of descent.This becomes more pronounced asthe aircraft gross weight approaches the maximum and rotorrpm s not closely monitored.

Maximum glide air speed is accompanied with a higher rate of de-scent, however, thehigher air speedaffords the pilot the advantage oftrading air speed for higher rotor

Figure 6

Velocity DueTo AscentResultant Neg. ift

The aircraft tends to continue to climb after the rotor system issuddenly unloaded by rapid reduction of coUective pitch.Movement of the cyclic control forward, during the air flowreversal, tends to aggravate the condition and cause furtherpitch up of the aircraft

rpm during deceleration which isadvantageous. The deceleration isless effective if the aircraft s belowminimum rate of descent air speed.The effectiveness of the deceleration may also be considered a function of air speed.

The facts favor max glide airspeed for those of us that are notas proficient as we would like to be.Autorotational EntrySuccessful autorotations beginwith a smooth entry. It takes 300to 500 feet to completely stabilizethe autorotation after the initialentry. The changes in pitch, roll oryaw moments are a result of rotorinflow changes and may occur withthe cyclic control in a fixed posi

tion. Therefore, any rapid controlmovement in response to thesechanges will only aggravate thesituation. In fact, flight tests haveshown that an aircraft at max grossweight in a climb at a slow airspeed will encounter air flow reversal if the collective s moved tooquickly. This can be understood ifyou consider the law of inertia. Theaircraft s moving at some rate up-ward. f the collective pitch ismoved to such an extent that therotor system is completely unloaded, an air flow reversal takesplace and negative lift is developed.Since the aircraft also has forwardspeed, two vector quantities areapplied to the rotor system and aresultant lift force is derived, utit is in the wrong direction Figure6 shows the resultant vector.

The dash lOis written to informthe pilot of the characteristics,capabilities and limitations of hisaircraft and offer him guidelines foremergency situations.

The book cannot offer all theanswers in all cases but a profes-sional pilot should be capable ofstudying and analyzing those situations that he finds in day-to-dayflying, regardless of the mission,and be able to outline a course ofaction that will enable him to gethis aircraft back down safely.

18 U. S. ARMY AVIATION DIGEST


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- , . , - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ~ ,,ttitude ttitude ttitude i,,,,CW Stanley E Whitman :,,,,

H V E YOU EVER given thought to how much How do we use it? "Some people," writes Jourard, :your attitude means to the people you contact "have a proven flair for transmitting powerful invita- :, and every day of your life? Each day -in every tions to others to regard life as pointless and hope- :way our lives entwine with others and our attitude less. They are gifted at getting others to 'give up, ,,has a great bearing on the individuals we meet. yield, give in.' " :I can remember a number of occasions when my We all know people like this. They have the "who ,day had a bright and shiny start, life was really worth- cares, what difference does it make?" attitude and :while, and given the proper incentive nothing could seem to make a special effort in spreading their gospel :deter me from giving Uncle Sam his dollars' worth at every opportunity. In fact, these people seem to :of effort. That is until I encountered the surly opera- have a special gift of preaching negativism. When one :tions clerk who changed my entire outlook for the comes under the influence of these people our life :day with only a word or two in the wrong tone of becomes inadequate. We seem to be pushed into :voice. belligerence and stupidity, a day, week or perhaps ,,Why does this have to happen? What could have even the rest of our lives becomes a wasted thing. We ,dgiven this man such an attitlude and why did it affect become a continuation of this original contact an ,me so? Could it be his attitude was more powerful again the web begins to tremble cockpit errors, :than mine? Why didn't the situation reverse itself? errors of omission, judgment, careless and unsafe :Instead of spoiling my day why didn 't I brighten up acts become the order of the day. Who knows where :his day? Frederich Buechner compares humanity the trembling will stop, whose life will cease to be, :to a spider web. "As we move around in this world," whose career will be ruined, whose soul will be ,,he wrote in he Hungering Dark and as we act scarred because directly or indirectly. you have con- ,,with kindness, perhaps, or with indifference or with tributed to an accident that a kind word, a smile, a ,hostility toward the- people we meet, we are setting word of encouragement could have prevented? :,the great spider web atremble. The life that I touch s a student pilot I can clearly remember the in- ,for good or ill will touch another life, and that in turn structors and check pilots that encouraged me on my :another, until who knows where the trembling stops way but for the life of me the gruff, unbending bearer :or in what far place the touch will be felt." of negativism is blocked from my memory. Their :As an aviation safety officer I can't help but won- names no longer exist and their faces are lost, shoved :der how many accidents occur when the trembling aside by a strong desire to forget. This has taken :stops or the touch is felt. For in our daily lives we are years to overcome because nagativism has a magnetic ,committed to use the finest, most expensive and force that takes a real effort to eliminate. Hard work :sophisticated equipment the Army has ever known. and an unyielding desire to succeed along with a :As aviators, regardless of age or experience, we are positive approach to my fellow man has been the :handed the responsibility of flying aircraft that we formula necessary to develop a feeling of positivism. :could not afford to buy in a lifetime. Yet, how often Let us, each and everyone, make an honest effort :have you heard, "Heck, the factory produces them to reflect the positive attitude, start the web to :in bunches like bananas, and if this one is broken trembling with a smile or kind word. Let the touch ',they will always get another"? Surely when 'a state- e felt in far places and live proudly with the results 'ment like this is made it is not made to a brick wall, of positivism. - :and most certainly the trembling will start and before Once again I ask, "What's your attitude? Posi- :it stops this very attitude will rub,off on many people. tivism or negativism?" Take a good look in the mirror :

n the Transparent Self Psychotherapist Sidney tomorrow morning and ask yourself, How do I want :Jourard claims that this process goes on all the time, the spider web to tremble? Whose life do I want to :we aU constantly issue unique and powerful touch today.?" :invitations to each other to live or die, to triumph or ,surrendet. :in part on liThe Invitation To live by Ardis Whitman. heClearly our individual influence can be profound. Reader s Digest, April 1972. ,,,

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ~ - - - - - ~19


22/52

O A BRIGHT clear day I andanother pilot departed in aV SF for a functional maintenancetest flight. During the landing gearcheck our day turned out to beother than routine.The landing gear was activatedfor extension in the electrical ornormal mode. o our surprise theindicators and light in the handleshowed all three gear in the transient position. After some discussion we decided to try and retractthe gear. First, we went to themanual gear extension procedure.Much to our surprise the gear again2

stopped somewhere in the transientposition, evidenced by an impossible-to-move .manual gear extension handle. We notified our homebase tower of he situation and.requested a flyby for a visual checkby the tower. Our request was approved and after completion wewere advised by the tower that allanding gear appeared to be extended halfway. This information was not tQO comforting but at leastwe knew our situation.Proceeding to a clear airspacearea we discussed the problem and.decided that we were in no hurry

to land in this condition. We haa full fuel .load at takeoff whicgave us time to avoid hasty actionand we did not want to land undethe circumstances with all that fueaboard. We decided that we wouldagain try to retract the gear sincthis had worked before. t also wafelt that a landing with the gear upwas preferable to one with the geahalfway down. So we deactivatethe manual extension system andactivated the electrical systemYou re right, nothing happeneexcept the gear motor told us in nuncertain terms that it could no

u. S. ARMY AVIATION DIGEST


23/52

We' certainly agree with CW3 Petersen aboutthe value of exchanging peNonal flying e Cperiences that have a teaching point. In his reference tohaving recalled reading about .a similarU-S gear problem, the DIGEST feels that CW3 .Petersen was thinking about the Weekly Summary of 25 November 1963 (see the end of this 'article). Although thisoccurred almost 10 yearsago, we find that many Army aviation peoplewho were around ,then still recall the particularsof this U-S incident. It paid off for CW3 Petersen. and his story may pay. off 'for you as. well.If you hav.e had a .similar experience as this ineither fixed or rotary ,wing qircraft, we d liketo hear from you. If you are not adept at writ-ing, don t worry about it. Just put your thoughtsdown on paper and send them to Editor, u.s. RMYAVIATION DIGEST, Department of ' NonresidentInstruction, U. S. Army Aviation School, Ft. Ruckel, AL 36360.But first, take time to read

raise the landing gear. Disappointment abounded. Since for better orfor worse both of us smoke thiswas the time. . . sit back, relax,light up and start exploring allpossible courses of action.The first item was emergencyprocedures for landing this air-craft in its present configuration. . . what I would do, what mypartner would do, when we woulddo it. We considered things suchas at what point prior to touchdown we would shut down the engines; ,woul4 there be enough time .to use the starter to position the

props for least damage; and howmuch of the runway would we request to be foamed. There was9,000 feet of it. Didn't we recentlyread an article that said to plan thetouchdown just prior to the approach edge of the foam? At whatp'oittt on the approach would weunlock the airstair door, of courseleaving the safety chain hooked,etc.?

After all. of these items hadbeen discussed and verbally rehearsed, we continued to investigate. the possible causes for ourpredicament. We decided that if

CW3 Dwayne L Petenen

the problem was not n a wheelwell we might be able t9 get to it.An inventory of tools abroardturned up one screwdriver with ablade of the size used , to adjustverticaL speed indicators and a 2inch socket set handle. Our planwas to remove the floor panels toexpose the gear mechanism.Things again looked grim becausethese tools were not adequate.Then, another brainstorm n-board were four water survivai kitswhich contained survival knivesthat had screwdriver blades. Mypartner started to open one of theseand at that moment I remirided him


24/52

that the inflation lanyard for theone man raft is connected to thecase zipper. We really did not needa cabin full of inflated rubber raft.After some effort the survival kitwas opened without raft inflationand we had an additional tool withwhich to work.Have you ever tried to removePhillips head screws with a regularscrewdriver blade that is also alittle large? Patience is the name ofthe game. By alternating the jobof flying and removing screws wefinally managed to expose the gearcross shaft, clutch, emergency extension mechanism, motor, nosegear chain and one area with nothing of interest. During this processwe also had to remove the rightfront passenger seat. It along withthe floor panels were stowed in therear of the ' cabin. At this time Iwould like to emphasize that I amin complete agreement with havingthe minimum required number ofpeople aboard during test flights.We were not crowded for workingspace and did not have other concerned people to worry about.

Next, we began a visual inspection of the gear mechanism. Aftera few minutes a strange object wasspotted. Care to guess what it was?f you guessed a wrench you wereright. It was a nice 2 x 6 inchopen end wrench. To be honestwe really did not need it but itdid give us an additional tool.

The problem was the placewhere this wrench was located.Coming out of the left side of thelanding gear retract gear box whichis driven by the gear motor is athreaded shaft. On this shaft is anut assembly which travels backand forth across the shaft. On topof the nut assembly is a smallfinger. Its sole purpose in life isto contact and activate the up anddown landing gear motor solenoidstop switches. The wrench waspositioned with one end against thebottom skin of the fuselage andone side against the cross beam,22

tilted to the left at about a 10 degree angle, with the upper endsnugly engaged by the nut assembly. Believe me, this condition allows nothing to move.After removing the waywardwrench with the assistance of thesocket wrench handle I proceededto lower the gear the rest of theway manually and with muchjubilation. Wait a second Thewhole thing is just as it was. I cannot move anything. The wrench isout, right? All else looks fine,right? Then what's wrong now?Talk about frustration.After more discussion we decided to again try the electricalgear system. Nothing moved. Sud

denly my partner shouted out thathe knew what was wrong. Duringthe activation of the electrical system he'd noticed the cross shafttry to turn. However, instead ofthe nut assembly moving to theright it tried to turn with the shaft.As mentioned earlier, there is alanding gear limit switch actuatoron this nut assembly which contacts the landing gear motor up ordown limit switches. There is ametal bracket with a slot in it whichis above the shaft. This acts as aguide for the landing gear limitswitch actuator. The actuatoractually extends through the topof the slot about one-eighth of aninch.Evidently when the wrenchjammed the nut assembly thethreads inside it and those on theshaft fouled, creating a bindingcondition. As the shaft and nuttried to turn, the landing gear limitswitch actuator was stopped by theside of the slot in the metal bracket.We knew what our new pro.blemwas but what do we do about it?We had no tools with which toremove the bracket so we decidedto use our trusty ratchet wrenchhandle to break off the actuator.We proceeded to beat the devil outof it and it broke off flush with theslot in the bracket. The system still

would not work.Ingenuity is really a great thing.By one of us using the socket handle to pry the bracket up and theother working the manual extension system we slowly but surelysaw the welcome sign of three flagsshowing the gear in the down position. Being good guys, the pumpingof the extension handle wasstopped when the flags said down.After going through all this it wasdecided that we would really like toknow if the light in the gear handlewas also out. This may have beena little foolish or unnecessary butthis was checked by my partneractivating the down , limit switchby hand while I placed the gearhandle selector in the down position (or rather making sure it wasin that position) and resetting thecircuit breaker. The gear handlelight was out and a press to test thelight showed that it did work.

The next steps were to againdeactivate the gear electrical system and make another flyby for avisual check of the gear position.This resulted in a very nice soundin the headset of "appears downand locked. " All of this wasclimaxed by a very uneventfullanding. Elapsed time from takeoffto parked on the ramp was 03 45.There .are I believe several goodpoints to come from this experienceand I list them here for your consideration:

Learn the aircraft systems andtheir locations. (My complimentsto the ground school personnel atthe U. S. Army Aviation School,Ft. Rucker, AL.) Know and constantly reviewall procedures. Analyze your situation and doit as slowly and thoroughly as possible, depending on time available. If there is someone with youdiscuss your thoughts and ideas.Let them do the same. If .space and weight permit always have a small flyaway tool kitonboard where you can get to it.U. S. ARMY AVIATION DIGEST


25/52

can e assured we do . . . iteven an add-on item n our pre- Practice and enforce tool con

Work hard at being profes

The following was published inVS' (then USABAAR's)

This one strikes close to home.the 22nd of November, twoUSABAAR sfor a proficiency flight. The

hourFour takeoffs and land

The right mam gear light

The gearA call was made to the. towerthis time, the gear .handle was

attempts to lower the. gearThe gear handle was then

The landing

up position. The clutch lever

no resistance to the40 fast strokes,Hght came on and

The nose gear indicator

An attempt was made to bringup electrically. The clutch

MARCH 1973

moved to the up position, and therelay circuit breaker closed. Thegear did not come up and the circuit breaker was again pulled. Atthis point, maintenance assistancewas requested through the towerand a low pass was made for avisual check. The main gear appeared to be down and the nosegear partly down.

After being advised of the actiontaken thus far, it was recommendedthat another attempt to lower thegear manually be made. With circuit breaker out, gear handle down,and clutch lever right, the emergency gear handle was pumped.After several strokes, it broke atthe base.By this time, USABAAR representatives and maintenance personnel were in the tower to lend ahand. The next suggestion was toattempt to remove the panel underthe right front seat. Fortunately,one of the pilots had' a GI canopener. Using the can opener as ascrew driver, and the emergencygear handle as a pry bar, he wasable to obtain limited access to thenose gear drive chain.In the meantime, a call wasmade to the factory and the situation was explained. The factoryrepresentative asked for the crewto check the nose gear chainsprocket where it attaches to thetorque tube for a missing bolt. Sureenough, the bolt was missing. Hethen advised that the airspeed beslowed to 65-70 knots, and the topchain be rotated forward, or thelower chain be rotated aft.The initial attempt to move thedrive chain resulted in approximately one foot of movement.There were definite hard spots beyond this travel. At just above stallspeed, the chain was rocked backand forth and finally passed the

hard spot. Movement of the chainwas extremely difficult. The limitedspace and the angle to the chain inwhich his arm and wrist had tooperate made the operation very

tiring. Maps were used to line theaccess area and prevent injuriesto his arm and wrist as he pulledthe lower chain. A piece of foamrubber from the seat cushion wasused to hold the lower chain whilepulling. Resistance to the last fewinches of chain travel reduced andthe nose gear light came on.

The tower then advised thatthe clutch be engaged, the landinggear handle be placed in the downposition, and the circuit breakerbe closed. When this was done,the load meters showed an increasein generator power, and the main .gear lights came on. Another lowpass was made by the tower and avisual check showed the gear down.A successful landing was made.Thanks to some heads-up flyingand a team effort, the aircraft sustained no damage, except for abent floor panel and ruined cushion.Inspection showed the cause tobe the loss of a bolt (FSN 5306-182-2005) from the sprocket assembly (FSN 1560-217-5721)which drives the nose gear chainfrom the torque tube. From thedirt and grease in the threads ofthe bolt, it was determined that thesafety nut had not been on the boltfor some time.

USABAAR .has several recommendations to make as a result ofthis experience:1 Recommend one time inspection of all bolts in the entiretorque tube assembly.2 Recommend inspection ofthese bolts at every periodic.3. Recommend all units equiptheir aircraft with a small tool kit.This kit should contain a minimum of one Phillips head screwdriver, one regular screw driver, apair of diagonal pliers, a pair ofregular pliers, and a small adjustable wrench.4. Recommend all aircraf t withretractable landing gear be placarded with emergency landing.gear procedures.

23


26/52

Asbestos Suited edicsStory by Specialist James Eakins

E A C H WEDNESDA Y at Ft.Bragg's (NC) Fire Pit No.1 agroup of daring specialists fromthe 132d Medical Detachment rappels from a hovering UH IH helicopter into a hellish sea of flames.The asbestos-suited medics andcrash rescue specialists are practicing an aircraft rescue operation. na real situation their job is to reachand evacuate occupants of adowned aircraft. Meanwhile, a specially equipped UH IH crash res-

cue helicopter hovers overheaspraying a fire suppressant onto thflames.Because fire is a major hazard iany aircraft accident, each of th132d's two UH IH helicopters carries two 25-gallon cans of a fire retardant known s light water.a crash situation the UH IH flienear the fire and, using a nozzle extension, sprays a path through thflames to allow the specialists treach the crewmen. The entire op


27/52

ractice ircraft RescuePhotographs y Specialist Earl Dawson

eration takes only 30 to 45 seconds.n August the 132d marked itsfirst year of crash rescue serviceto Ft. Bragg's Simmons Army Airfield Captain Glenn W Flint, commanding officer, said: Since ouractivation it has been left up tous to work out specifics in performing our mission. n our first yearwe have tested out many procedures and I am convinced this is

one that works.

The 132d services a 20-mileradius of the airfield. f an aircraftputs in a distress call, the teamgoes into immediate action, flyingdirectly to the aircraft and escorting it to the airfield. Should thecraft go down, an immediate rescue of the personnel can be accomplished.The 132d is one of four suchunits in the Army that stays onconstant alert for the sake of Armyaviation safety.


28/52

TRIKE T RI H

Writing or The IGESTO.K., so you re not Hemmingway. Not everyone can be aprofessional writer, but everyone should be able to expresshimself in writing, regardless o his profession. Here sthe shove you needed to get started on your IGEST article

SAVED ANYONE'S life lately?'This question might be moresignificant than you think. It's justpossible that you may possess someknowledge or have benefited fromsome experience that could savesomebody's life if they knewabout it You can tell them in theu. S. ARMY AVIATION DIGEST.No matter what your job is,there is something about it or something that you have experiencedthat is of interest to the, professional people who read the DIGESTeach month. You now what ishappening and, whelie it is happening and we invite .you to shareyour experiences with others interested in Army aviation. Whileit may not necessarily save a life,6

it could easily save time andmoney.The DIGEST continually seeks tokeep those involved n Army aviation informed about the most recent advances in aviation safety,operations, maintenance and technology. The magazine also servesas a sounding board for new ideaswhich further the cause of Armyaviation and t promotes esprit decorps by noting significant accomplishments.You, the reader, can do yourshare to help make this goal areality by sharing your knowledge,experiences and ideas through theDIGEST.This is how to do it. Anyone cansubmit an article to the DIGEST .When your manuscript is received

several things happen. First, youget a letter of acknowledgement;then if the DIGEST prints the article,a letter crediting you with havinghad an article published is placedin your 201 file at your branch atDepartment of the Army. Third,your published article is enteredin the monthly award competition.f you win, you receive an engraved

plaque plus a 25 U. S SavingsBond. Also the article becomes eligible along with other monthlywinners for the annual awards contest. The three best of the year areselected and the winners receiveengraved plaques and aU. S Savings Bond of 250 for the firstplace article, 150 for second and100 for third.You don't have to be a profes-U. S ARMY AVIATION DIGEST


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sional writer to contribute to theDIGEST. Our authors come from allwalks of life. Don t worry if yourarticle is not perfect grammatically or does not conform to DIGESTstyle. The staff will edit the manuscript and correct such errors.Material submitted to the DIGESTvaries from pictures, letters, ideasand suggestions to full articles. Anymaterial that falls within our mission is welcome. However, as anofficial Department of the Armypublication, the DIGEST followsguidelines which limit the publication of certain types o f articles. Forinstance, material which tends topublicize units or individuals forthe mere sake of pUblicity is notprinted. f you have any doubtabout the acceptability of the item,either send it and let u be thejudge or query the DIGEST prior towriting the story.Whenever possible an authorshould contact the -DIGEST beforebeginning his article to be sure heis on the right track. This can bedone in person, by telephone orby mail. All military personnel areauthorized to deal directly with theDIGEST. To ensure technical accuracy, manuscripts .are reviewedby experts in the particular fieldwith which they deal. For example,a story on helicopters normallywould be reviewed by the U SArmy Aviation School at Ft.Rucker, AL, and an article dealing with aircraft design or modification can be sent to the U. S ArmyAviation Systems Command at St.Louis, MO. Many articles are reviewed by the Department of theArmy to ensure compatibility withofficial government policy and toensure that they do not containclassified information.

The author has the option ofclearing his story through the Office of the Chief of Information,Headquarters, Department of theArmy, prior to submission, or hemay send the manuscript and letthe DIGEST handle the clearance.MARCH 1973

These safeguards protect not onlythe author but also the DIGEST andthe government against printingmisleading, false or even libelousinformation. Also, reviewing agencies often improve an article byadding current information thatmay not be readily available to theauthor.What would we like for you towrite about? Anything covered inour mission is suitable. The following topics are offered as suggestions(a more detailed list of suggestedtopics can be yours upon request) : Army aviation subjects oftimely interest. Maintenance, operations, safety, etc., practices that save time,money and material. New uses for Army aviationor its equipment. War stories or personal flightexperiences that bring out new orunique tactics, techniques or safetyprocedures. All phases of professionalismin the aviation program. Research and developmentprojects. Humor, with a teaching point.

Historical aspects that tendto establish an Army aviation heritage or to build esprit de corps.

Anything expressing originalconstructive thought on Army aviation.In selecting a topic it is generallybest to choose one with whichyou re familiar. f you or some

one in your unit has found anew, better or safer way of doingsomething or has had a personalexperience of value to others in theprogram, write about it.Once you have made your selection, make an outline of what youwant to say. At this point, a visitor call to the DIGEST could makethe difference between failure orsuccess. A member of the staff willbe able to tell you whether or notsuch a story would be of value tothe DIGEST and how best to proceedfrom there. With a firm outline youwill find that you won t ramble oromit important points. Keep theaverage reader in mind.

Don t assume that all the readerswill understand terms that you useevery day in your job. Identifyall such terms in your article. Byhaving an interesting and attention-getting lead paragraph youwill be able to catch the reader sattention and then focus it on whatis to follow.Illustrations are important sup-


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plements to the written word andwill be helpful in holding readerattention throughout the article.The continuity of the story mustbe developed from the very beginning and should not be overlooked

when the concluding paragraphsare written. f the story doesn thave a surprise ending or a naturalconclusion you might try tying theending back to something mentioned in the lead paragraphs.Another important item to beaware of, especially when writingabout technical subjects, is the accuracy of facts and figures. Although we will check them for accuracy, this detail is really yourresponsibility. f you are unableto verify statistics, call this to ourattention.Permission must be obtainedfrom copyright owners to reprintquotes of more than 200 words.

Plagiarism-an ugly word for stealing another author s original work-could make you, the DIGEST andthe government subject to legalaction. Be sure to credit yoursources if the idea is not solely yourown

Whenever possible include appropriate, captioned photographs,artwork, charts or diagrams to il-lustrate material. The readabilityof any article is enhanced by goodillustrations. If you are not surewhat is needed, send what you haveand let us decide what to use.Below are some general guidelinesconcerning supporting material: Use protective cardboard forillustrations during mailing and donot use staples or paper clips onpictures. Use cellophane tape ormasking tape to attach captions tothe back of the photo. We prefer black and whiteglossy prints or their negatives. Wecan use color photos but they donot reproduce as well. Get a professional photographer if possible to take the pictures. Captions should include the28

Get something down on paper as soon as pos-sible; it gives you a tool to work with. Tell thestory to yourself and write it down as you do,using your outline to keep you from wanderingtoo . far off. At, this point don't worry aboutsuch things as grammar. sentence structure andspelling. Read what you have written and add any de-tail or little thing you may have forgotten. syou rewrite, correct your grammar and spelling. Now look at your article obiectively. If youhave said anything not directly connected tothe story or if there is anything in it that doesnot carry the story forward, cut it out. Put the story away for a few days to sleep.Then take it out and reread it. After this restyou will be able to see many flaws you let pass.

full name and rank of each individual, if known, and a descriptionof what is taking place in the photo. Be sure to credit propersources for illustrations. Obtainwritten permission to use photosfrom outside sources, or advise usof ownership so that we may obtainthis permission.We prefer that manuscripts betyped on standard size bond paper

-double-spaced. Do not send carbon copies unless you verify thatthe DIGEST is the only recipient ofthe article. If you do not have access to a typewriter, we will behappy to receive your handwrittenmaterial.Manuscripts should run from2,000 to 3,000 words, but we realize that many subjects require agreater or shorter length. The bestguidance we can offer is to makethe ~ r t i l e long enough to tell thestory without omitting meaningfulinformation or adding excesswordage that adds little to the effectiveness of the story.It is important that you send ashort biographical sketch to includeyour rank, Social Security number,branch, a permanent address; current assignment and other information you feel is appropriate. Weare especially interested in any significant facts in your background

that tend to lend credence to thesubject matter about which youwrite. If you change assignments,address or are promoted before wehave printed your article, send thenew information to us.While style and composition aredefinitely important , our main concern is what the author is sayingrather than how he says it. We cancorrect grammar and smooth outan article, but it is solely the taskof the author to convey the meaning and thought that he is trying toget across.Although there is not a monetaryreward for authors who do not winthe monthly award, the satisfactiongained by writing for the DIGESTwill help you in your future militarycareer. The ability to express yourself clearly and concisely in writing, as well as in speech, is a requisite of any profession. And youwill be credited in your 201 file foryour article if the DIGEST prints it.

Begin writing your article today.Send your manuscript to the u. s.ARMY AVIATION DIGEST, Ft. Rucker, AL 36360. For those whowould like to visit or call, theDIGEST office is in building 5703at Ft. Rucker and the telephonenumber is-commercial: 205)255-3619; AUTOVON: 558-3619.



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. Haven t You Got y Clearance Yet?ontinued from page

if you happen to be calling SaltLake Center around midnight, butdefinitely out of order at 1100hours local in the WashingtonTerminal Control area.

The increase in air traffic andcorresponding radio traffic, as youknow, has resulted in reducedmandatory reporting and clearancereadback requirements. But occasionally, radio discipline meanstalking a bit more than requiredby the rules.

Now, I realize that a simpleRoger will suffice to acknowledgeunderstanding of a new altitudeclearance under the .new rules.However, when it's obvious that acenter controller is straining tosandwich other traffic into airspace

I'm vacating, it's just good commoncourtesy to read back the altitudeclearance. It's also a good idea toput yourself in the ~ h o s of thetower controller who, in an effortto expedite traffic, clears an aircraft to Taxi into position andhold. While a simple Wilco willdo, a position and hold acknowledgement is better. Instructions tohold short should also be clearlyacknowledged.

One more pet peeve: There isno control tower in existence thatcan manufacture an ATC flightclearance, and probably darn fewthat would i n t n t i o n ~ l l y conceal orwithhold a valid clearance. Whena pilot is strapped into a 115 degreeFahrenheit cockpit, waiting to startengines, he can be excused for

There's no control tow-er in existence todaythat can -manufacturean ATC flight clearance

making an occasional query on thestatus of a clearance delay. On theother hand, I've heard aircraft commanders translate their embarrassment for late takeoffs by gettingtough with ground control. The reaction simply means that the towersupervisor has to discontinue supervision of the younger controllerswhile he tries to reduce the noisefrom the irate aircraft commander.f a real problem is developing inthe traffic pattern, cross off one pair

of experienced eyes that could behelping to resolve it.

To this point, I've been paintingthe aviator as the villian of theradio discipline team, but it worksthe other way, too. Someday, I dlike to disabuse that fellow inRAPCON of the idea that Ipossess a photographic memory. Irefer to the scene where I m in thesoup, in a descending turn, and I mhanded off from center to approachcontrol. Initial contact is made, andin one mouthful, I m given a newaltitude clearance, a new vector,altimeter setting, active runway,ceiling, visibility, winds, remarksand missed approach procedures.I t would be nice to claim that I msmart enough to consistently assimilate all that. But to behonest, 8.4 flying hours per monthjust doesn't equip some peoplewith that ability. WHEN THETIME PERMITS, friend controller, please give me all thosenumbers, a few at a time.Reprint courtesy T AC A TTA K

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ublicationsHow can I make sure I get the ARs other VApublications and VA blank forms I need? ASOAR 310-2, August 1971 , supported by change 120 June 1972, and DA Pamphlet 310-10, 14 February 1969, is the bible for distribution and requisitionof Department of the Army publications and blank

forms. According to this regulation, an organizationin the field should be able to get the publications andblank forms it needs if the procedure described in thefollowing paragraphs is followed.n order to get publications to the people whoneed them, the U. S. Army Adjutant General Publication Centers (USAAGPCs) distribute and resupply publications directly to organizations and units ,using the pinpoint distribution method. A commander of a brigade, group, regiment , battalion, company, battery or comparable command may establishan account for the publications required by his head

quarters at either or both of the USAAGPCs listedbelow:USAAGPC1655 Woodson RoadSt. Louis, MO 63114

(Some types of publications stocked: All technicaland supply publications such as technical manuals,technical bulletins, lubrication orders, supply bulletins and supply catalogues.)USAAGPC2800 Eastern BoulevardBaltimore. MD 21220

(Some types of publications stocked: Army regulations; DA circulars, general orders, pamphlets andposters; certificates for awards and decorations;doctrinal , training, organization and miscellaneouspublications. )To establish an account with a USAAGPC, a commander submits a Request for Establishment of aPublications Account (DA Form 12), when hesends in anyone of the DA Form 12-series, a .pinpoint subscription form. The subscription form is

used to establish the organization's publication needsat the USAAGPC. When a commander submits thesecompleted forms, he has subscribed to the publications he needs for his headquarters. TheUSAAGPC will then assign that unit an accountnumber. The subscription forms are pre addressed tothe appropriate USAAGPC to make the subscriptionprocess easier. Two pinpoint subscription forms ,Requirements for Army Aviation and Army AvionicConfiguration Publications (DA Form No. 12-31)and Requirements for Army Avionics Publications(DA Form No. 12-36), will be of interest to many3

If you have a questionconcerning aviation accidentprevention write toCO USAAAVSATTN: Orval RightFort Rucker AL 36360

aviation subscribers.A word of warning: The next higher headquartersmust approve requests for accounts from companies,batteries and detachments.A commander's responsibilities are not limited toestablishing the account and submitting the initialrequisition. He must ensure that both the type andnumber of publications subscribed for are actuallyneeded. In this regard, a commander should requestonly those publications applicable to his headquarters.He should review his subscription forms at leasttwice a year to confirm that his unit is receiving

U. S. ARMY AVIATION DIGEST


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needed publications, but is not getting unnecessaryones. The same subscription form (DA Form 12series) is used to submit changes. The change boxshould be checked and changes indicated in thoseblocks on the form for which additions, deletions orchanges are required. Instructions are found on theback of the form.For the convenience of the subscriber, USAAGPCallows write-in subscriptions for new publicationsnot listed on subscription forms. When new issuesare announced either in a DA circular or in aUSAAGPC letter, they may be ordered by the writein method.

In any correspondence with a USAAGPC regarding an account, the account number assigned theorganization by that particular USAAGPC must bereferenced. And a last suggestion concerning publications: If the designation of an organization is changed,a change showing the new designation and referencingthe account number should be submitted to theUSAAGPCs as soon as possible.Bulk quantities of blank forms, including the 2397series, are provided to the publications centers inoverseas commands and to installation publicationstockrooms in the Continental United States(CONUS) to supply using units. However, someoverseas commands, organizations and activities thatare not satellited on a command with a publicationcenter receive blank forms directly from USAAGPC

as do CONUS installations and off-post activitieswhich neither operate stockrooms nor are satellitedon organizations with stockrooms. These groupsestablish an account with USAAGPC by submittingthe DA Form 12-series. Then blank forms can eordered on the DA Form 17 and 17-1.However, most using units requisition blank formsfrom installation publication stockrooms or fromoverseas command publication centers, as appropriate. DA Forms 17 and 17-1 are used. Units are

allowed to keep 60-day supplies on hand.To obtain distribution of the u. S. ARMY AVIATION

DIGEST and DA aviation safety posters, submit DAForm 12-4 in accordance with instructions on theform.

To obtain distribution of U. S Army Agency forAviation Safety publications, submit your request toCommander, USAAAVS, ATTN: FDAR-EP, Ft.Rucker, AL 36360.Crashworthy Fuel Tanks

Are crash worthy fuel tanks scheduled. or retrofiton Army aircraft now in the inventory that don thave them installed? AviatorMARCH 1973

Yes. The completion date for installation of thesetanks in Army aircraft is as follows:UH-ID/ H-June 1973AH-IG-December 1973UH-IB/ C-July 1974CH-47C-July 1974OH-58A-September 1974CH-47A-July 1975OH-6A-December 1975CH-54A/ B-September 1976ircraft isplaysIs there a regulation governing static display ofaircraft at civil air shows? CommanderAR 360-61 covers static displays and states, amongother things : Static display is a ground display ofany aircraft, and its related equipment not involving flight , taxiing, or starting of engines. The aircraft

must be in place with power off prior to assembly ofspectators unless the aircraft can be towed or otherwise transported into the area with safety to spectators observed, and may not be moved until spectators have departed. Supervisory personnel of anyunit that may be called upon to furnish an aircraftfor display at a civilian function should familiarizethemselves with the particulars of this regulationand ensure that the aircraft is put in place and movedin accordance with outlined procedures. You wouldbe interested in an article appearing in the December 1972 AVIATION DIGEST entitled Static Displaysand AR 360-61.Safety Meetings

Are monthly flight safety meetings required byAR? ASOParagraph 5 of appendix 6 to AR 95-5 states thatinformal aviation safety meetings should be scheduledperiodically at least one per month) for all aviationpersonnel. Most Army supplements to this AR statehow long a safety meeting should last and oftensuggest subjects to be covered.

Flight JacketsIs there a regulation that says that aviators mustwear flight jackets? NonaviatorNo. AR 95-1 says that flame retardant clothing,leather boots and flight gloves will be worn by theflight crew on combat, tactical training, test or similar flights that involve unusual hazards and at othertimes as prescribed by unit commanders. The flightjacket is not flame retardant, and Nomex flightjackets are still in the service test stage, with fieldissue expected in Y 1975.

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rnoldR ambertirectorate tor Education r f Prevention

US VS

W RNINGSIGNSM R WILSON played golf as often as he could,

which wasn't nearly often enough to suit him.His hardware store took up most of his time andbusiness came before pleasure.Seven pars and three birdies in a single round waswell above average for Mr. Wilson and on this dayhe stayed at the 19th hole longer than usual. Heenjoyed several beers with friends while giving astroke by stroke description of the three birdies andtwo of the pars that could have been birdies had. itnot been for the long putts he missed by inches.Leaving the clubhouse, he threw his clubs in theback seat of his car and drove by the high school to pick up his son. It was one of those days that lookedas though the predicted early evening thunderstormswould materialize. Black clouds started billowing likesmoke from an oil fire and the early evening wassuddenly pitch-black.Mr. Wilson told his son, Let's get home beforethe storm starts. You drive, but be careful. Theywere on a two-lane asphalt paved road and in a matter of minutes the heavy downpour started.As young Wilson approached a busy intersection,he applied the brake and the rear of the car startedskidding to the right. He steered the car sharply to the3

NOP SSING

left which intensified the skidding. The car spunthrough the intersection and was hit from the rightrear by another car approaching from the right. Theimpact was in the opposite direction of spin and wasso great that the right door was torn from the Wilsoncar. Mr. Wilson was thrown from the car and killedinstantly. Both cars overturned and the driver of theother car was pronounced dead upon arrival at thehospital. Young Wilson was wearing his seat belt butreceived serious head injuries caused by flying golfclubs.A road sign with the words SLIPPERY WHENWET was found among the twisted wreckage inthe intersection. A witness, following the Wilson car,stated that young Wilson was not exceeding thespeed limit but did not start braking SQQJl enough considering road conditions.Investigating. officers attributed the cause of theaccident to the fact that the car was being driven byan unlicensed, inexperienced ' 15-year-old boy. naddition to not allowing adequate stopping distancefor existing road conditions, the boy turned the steering wheel in the opposite direction of the skid;A contributing cause factor was cumulative deposits of oil on the pavement fromcars stopping at


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