Army Aviation Digest - Sep 1984

8/12/2019 Army Aviation Digest - Sep 1984

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US RlSCI SUPPORT CENTERP O BOX 620577FORT RUCKER l 36362 0577


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101418 Wind22 PEARL SDES Report To The Night

Goggles Training and Operations26 Aviation Notes: AdvancedSchooling; Personnel ChangesiMllPERCEN;New Army Test28 Antitank Guided

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t:n49ctiive ess: WhyTE MSPIRIT8 :

Honorable John O. Marsh JrSecretary o the Army

r i ~ l a d i i e r General Wayne KnudsonAviation Off icer ODCSOPSRrit lIRrii lu Genera. P) D. ParkerAssistant CommandantU.S. Army Aviation Center

RichardEditor

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VI TION EMPLOYMENTinSpecial Purpose Operations

This is the i rst in a series of articles the viation Digestwill publish examining offensive defensive and special purpose

operations and employment relative to rmy Aviation.Discussed in this issue are five speci l purpose offensive

operations; subsequent articles will cover the five basic offensiveoperations and four defensive operations.

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Captain Ron KleinCombined Arms Division

Department of Combined Arms TacticsU.S. Army Aviation Center

Fort Rucker, AL

GREAT DEAL of emphasis hasbeen placed on the dramaticchanges taking place in ArmyAviation. Concurrently, it is certainly appropriate to look forward to our potential

contributions with combat Aviation brigades,AH-64s and across the forward line of own troops(FLOT) deep attacks. However, the most frequentemployment of Army Aviation will continue to bein conjunction with Armor and Infantry operations. Considering this, t is imperative that everyaviator be familiar with the specific ground missions, the peculiarities of e ch operation, and theconduct of each if we are to: fight outnumbered and win survive

contribute in the most complementary manner, and establish the Aviation Branch as a full partnerin the combined arms team.Our professionalism mandates that everyone whomay serve as a commander, operat ions officer orliaison officer be fully competent to advise theground commander on the best manner to incorporate Army Aviation.There are 14 operations covered in FM 100-5,Operations. These include the following specialpurpose offensive operations: Reconnaissance in force Raids Feints Demonstrations Relief to continue the attack.

This article examines special purposes operations emphasizing Army Aviation s role in each.There will be followup articles discussing offensive and defensive operations in subsequentissues.

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RECONN ISS NCEIN FORCE

RECONN ISS NCEIN

FORCE

A reconnaissance inforce is a limited-objectiveoperation by a considerableforce that obtains informa-tion and locates and teststhe enemy dispositions, strengths and reactions. Although a commander normally has access to

many information and intelligence sources(patrols, side looking airborne radar, refugees,prisoners of war (PWs), reconnaissance aircraft,etc.) there will be occasions when very little isavailable (due to strong enemy defensive posi-

FM 100-5, page 9-2.

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tions abundant enemy air defense artillerysparsely populated areas, etc.). In this type ofsituation the commander may elect to attack andthereby determine the enemy s responsiveness,morale, typeof weapons on hand, etc. During thedecisionmaking process the commander and hisstaff weigh the expected losses to determine ifthe potential gain in information justifies the riskof this attack.The attacking force will normally be a tankheavy2 battalion sized task force TF)3 but it maybe a brigade or an armored caval ry reg i ment. 4 Thecommander begins an attack across the FLOTand moves toward a terrain objective to force amajor enemy reaction. The TF will pull back intofriendly territory if met with an overwhelmingforce. As a result of this attack the TF commanderwill not only capture PWs and some enemy equipment but more importantly will also have achievedhis primary goal of determining what the enemy sdefensive positions are, the size of the reactionforce and the ability of the enemy to respond tosuch an attack. Even if the attacking force is unsuccessful at penetrating the FLOT it will stillhave obtained important information on theenemy s defense. The operation wi ll be similar toa del iberate attack except that normal i ntelligence preparation will be sparse.Because prior intelligence is so limited thechances are good that the enemy s strength andresilience will have been seriously miscalculated.For this reason unusually large reserves are an integral aspect of reconnaissance in force operations.lf the enemy is unable to react quickly or forcibly to the attack the opportunity is ripe tocapitalize on the unexpected success and immediately reinforce the attack. On the other hand,if the enemy reacts much quicker and strongerthan anticipated the situation may deterioraterapidly for the outnumbered attacking force. Theattacking force will need immediate assistance inextricating itself. The reserve force must be readyto perform either mission. As with all reserveforce missions the timing of employment iscrucial; too early or too late (or worse yet, not at all)wi II mean that a strong available asset was notused at the decisive time and place to affect thebatt e outcome.

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rmy viation in the Reconnaissance in ForceThere is no force on the battlefield moreresponsive than Army Aviation. Regardless o

swamps minefields forests or mountainshelicopters can be at the desired locat ion withinminutes of a request. In this particular operationthe reserve force is an ideal mission fohel icopters.If the call comes to reinforce and continue theattack, assault helicopters can place troops onflanks to keep the penetration gap open and reinforce the leading elements. Attack helicopterscan locate the lead ground units in contact andmake a significant contribution to momentumThe attack hel icopter can also stop, delay or impede enemy reinforcements after the air andground cavalry forces have located them.If the request is made to assist in extricatingthe attacking force, assault helicopters can be usedto pull back dismounted troops, soldiers fromdisabled vehicles, and personnel slowed by captured PWs or enemy equipment and weaponsUnder some circumstances, assault helicopters maybe able to move troops from one delay positionback to the next. Attack helicopters will be particularly useful in providing overwatch suppressive fires to allow for an orderly disengagement and the repositioning of armor and infantryunits in a delay. Attack helicopters may also beused to delay enemy reinforcements from arrivingbefore friendly forces have pulled back across theFLOT.

FM71 -100, page4-38.3 FM 71 -3, page 3-31 and FM 71 -101 , page 419.4 FM 17-95 (draft), page 3-38 .5 FM 100-5, page 93.6 If the raid mission is to destroy enemy materiel or some installat ion in

enemy held territory, Air Force assets should be considered . The AirForce has some extremely capable, all weather, precise and survivableweapons systems like the F111 that should normally be the first cho ice fosuch a miss ion.

7 F M 71-3 , page 332 .

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R IDS

RAID

A raid is an attack intoenemy-held territory for aspecific purpose otherthan gaining or holdingterrain. 5 The raiding forcemust accomplish its mission and withdrawbefore the enemy can effectively react.

The most common raid missions are to: Capture prisoners or enemy materiel. Rescue friendly personnel. Obtain specific information. Deceive or harass enemy forces. Destroy enemy materiel or instal lations. 6The most apparent difference between raidsand reconnaissance in force operations is intelligence preparation. Raids require current intelligence and are often rehearsed on sand tablesor mock-ups in detail prior to execution. Raids

may be conducted by ground forces, helicopters,airlift assets or a combination. Due to the absolute need for surprise they will normally be conducted during periods of limited visibility. In addition to the detailed planning required of any attack these operations must plan for thewithdrawal phase in the same detail. Although theplanning is very detailed and therefore qui te centralized, the execution should be decentralized topermit flexibility.7

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As in any attack, the fire support plan must beplanned, coordinated and conducted wi th precision. Although field artillery may be able to suppress and destroy enemy weapons systems in theinitial crossing of the FLOT and may be able toprovide suppression of enemy air defenses for aircraft in the early portions of the route, it is unlikelythat field artillery will be able to reach the objective; suppression of the objective may be in theform of close air support (CAS) or attackhelicopters. Often the objective will not be firedupon in preparation due to the requirement forsurprise. A feint or demonstration may be plannedto occur simultaneously elsewhere on the battlefield to divert attention (and consequently rapidcounterattacks) away from the raiding force.Army Aviation in Support of a Ground ForceConducting the RaidWhen ground forces conduct raids they willnormally be battalion sized task forces. The forcewill move rapidly conduct the mission andwithdraw by a different route. The raiding forcedepends on stealth, speed and precise timing forsurvivability. The planning and execution of themission will take into account the fact that theraiding force will not have the necessaryfirepower to defend or delay against anythinglarger than the enemy s securi ty force.It would be unusual for Aviation assets to movewith such a ground force (due to mobility differences) but they may often be employed to meetthe ground force at the objective to make a majoraddition to firepower. Attack hel icopters could aidin destruction, confusion, create diversions andprevent enemy reinforcements while the groundforce completes its mission. In different terrain,assault helicopters with TOW (tube-launched,optically-tracked, wire-guided) missile teams anddismounted infantry could do that.In the event a major enemy reaction occurs during the raid, helicopters will be needed to assist inthe withdrawal or emergency extraction of theground force. As with the reconnaissance in forcemission, the responsive addit ion of firepower mayhold off the enemy reaction force long enough forthe ground force to withdraw. Attack helicopterscould also contribute to a delay operation by suppressing enemy direct fire systems during the


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ground force s bounds back to subsequent positions. If an emergency extraction of the groundforce is necessitated, assault helicopters maywell be the only means available due to time constraints and terrain limitations facing the groundforce. Attack helicopters will simultaneously provide escort and poss ibly assist in the destructionof abandoned U S vehicles.Army Aviation Conducting the RaidThe use of helicopters as the sole means toconduct the raid is a natural outgrowth of thetechnological development in helicopters and thechanges in doctrine. The raiding force may bepri mari Iy made up of attack helicopters and/orassault helicopters. For example, a pure attackhelicopter force could perform a mission todestroy a command post or a multiple launchedrocket system battery. Due to the increasing tactical emphasis on cross-FLOT operations therewill be a greater demand for attack helicopterraids.Raids conducted with assault hel icopters mayemploy the helicopters as the only means of inserting and extrac ting the raiding force. On other occasions the lengthy time required for the force tobe on the ground could mean that the waitinghelicopters would be unnecessarily vulnerable toattack and the force needs to be inserted by othermeans (airdrop, amphibious landing), then extracted by helicopters The Son Tay raid isperhaps the most famous example of a helicopterraid and is well worth reviewing to gain an appreciation for the detailed planning required. sLike any air assault operation, a raid also hasfour basic steps; the ground tactical plan, the landing phase, the en route phase and finally theloading phase: The list at right is an example ofplanning considerations applicable to each.

A discussion of the complete operationalplanning considerations for the execution ofhelicopter raids would require far more detail.This discussion of helicopter raids is not intended to be all inclusive. An artic le on planning considerations, constraints and trade-ofts for execution of the raid would be far more extensive thanthis. The only intention here is to review the appropriate use of helicopters in the tactical operations (not the specific execution).

GroundTacticalPhase

RAID PHASESHow many troops will be going in?What deception plans are part of theoperation (CAS, joint air attackteam, feints or demonstrationselsewhere)?What time of day (or night) willthe landing occur?How long will the force be onthe ground?What are the contingency plansif aircra ft are lost en route or atthe objective?

Landing Will landing be on orPhase away from ttle object ive?Does the commander want to use oneor multiple landing zones (LZs)?Do you want to use attack helicoptersor Air Force assets to prepare the LZs?Do you want to use pathfindersto assist in landing?How many aircraft can bediverted to make falseinsertions , or do you want to make aseries of false insertions en route?

En Route What flight corridors willPhase be established?Can you arrange for escort aircraft(Air Force or attack helicopters)?What are the refueling andrearming requirements en routeor at the objective?How are smoke and chaff used toassist in deception?Where will passage points , pilotpickup points and air controlpoints be established?

Loading How many pickup zonesPhase (PZs) are requested?Are the airmovement tables (toinclude the bump plan) complete?If the flight is larger than the PZ willpermit at one time where will theaircraft meet for the initial point?

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FEINTSA feint is a limitedobjective attack designed

to divert the enemy sattention. Most oftenfeints are conductedprior to or during a main attack in an effort todeceive the enemy This would cause a shift in enemy

reserves and forces to meet the feint andconsequently lessen the resistance the mainattacking force would meet. Also, there may beoccasions in the conduct of a dynamic defense(that includes several spOiling attacks) whenfeints will be used independently to keep theenemy moving and to disrupt his preparations foran attack. A series of feints may also be used toharass the enemy, confuse him, and in somecases, cause him to become careless. 9 Units

8 Benjamin F. Schemmer, The aid (New York: Harper Row, 1976).9 FM 90-2, page 2-3.

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conducting a feint must execute the attackviolently to convince the enemy that the feint isthe mai n effort. f t he fei nt succeeds inpenetrating the enemy's defensive system, thecommander may exploit his unexpected successwith follow-on forces or change the course of themain attack to follow the feint. Obviously,planning for such contingencies must be madewell in advance. t is not necessary for the feintattack to penetrate the FLOT since a violentlyexecuted attack may still cause the enemy to shif this reserves and other main line forces to theapparent threatened sector.

rmy Aviation in Support of the FeintIn order to succeed, the feint must give theappearance of a serious attack. Therefore, thehelicopters normally associated with an attackmust be present. In addition, attack helicopterscan attack flank positions to prevent enemytroops from moving to reinforce the threatened. sector. After a breakthrough has occurred theycan also make an invaluable contribution towardincreasing the momentum of the attacking forceby destroyi ng enemy forces and contai n ngbypassed pockets of resistance. Attackhelicopters may also be used for the initialassault. However, in high intensity battles.speCIal attention should be given to the expectedvolume of enemy indirect fires in the immediatearea of available battle positions.If the decision is made to reinforce anunexpected breakthrough with either deploymentof the reserves or an alteration of the main attackroute, helicopters would be particularly useful. Inthis case, it is critical that the momentum of theattack be maintained during the interim periodrequired for reinforcements to arrive. Again, noforce on the battlef ield is more responsive thanArmy Aviation. Assault helicopters should be fullyemployed expediting the movement ofdismounted troops and supplies to the lead unit incontact. Attac;k helicopters can impede, destroyor delay enemy reinforcements and assist thelead ground in contact by increasing the rateof advance. Arr cavalry forces can continue toscreen flanks, report lateral movements of enemyforces and report critical information from allsectors.

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DEMONSTRATIONSDemonstrations serve

the same purpose asfeints but differ in that nocontact is made with theenemy. An example ofthis would be a few Indians on the other side ofthe hill mass dragging tree limbs to raise enoughdust to convince the horse cavalry troopers thereis a major force and consequently lure thetroopers to the desired location. Althoughdemonstrations lack the realism of the feint, theabsence of physical contact with the enemyfacilitates employment of the demonstrationforce elsewhere. 1 0 Like all deception operations,demonstrations require a thorough knowledge ofthe enemy and his collection sources as well asintegration with friendly plans.Army Aviation in the DemonstrationUnder normal battlefield conditions the noiseassociated with helicopters is a real liability. Indemonstrations, however, it is the noise thatmakes helicopters so useful. During limited

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visibil ity conditions the noise of movinghelicopters combined with a soldier's naturatendency to exaggerate the enemy s numbersmake helicopters an effective tool. Demonstra-tions vary so greatly in execution that it is difficultto specify Aviation's contribution in a normaldemonstration. A better methodology may be toconsider the following examples.A few empty helicopters could make repeatedlandings and takeoffs from a likely location atnight orduring obscured weather condi tions in aneffort to convince the enemy that friendly forcesare moving from one staging area to another. Thisshould be combined with some vehicular noise athe same time. As enemy listening posts detectsuch noise and enemy radar catches momentaryblips moving in the same direction, the enemymay well o n l u d ~ that a large redeployment istaking place.A second example might be helicoptersplanning an amphibious assault to an island orpeninsula. Helicopters could be used to makerepeated landings at one location and cause theenemy commander to draw some of his forcesaway from the true assault objective. In difficulterrain and a low or mid-intensity engagementsuch an assault would not be expected to makecontact with the enemy (thereby qual ifying as ademonstration).Sling loading an artillery section into a flankposition or a deep location is another example ofhelicopter use in the demonstration. On anonlinear battlefield several scenarios may befeasible without resulting in direct engagement ofthe enemy. A few artillery pieces firing from adecisive sector would be located accurately bythe enemy (via radar, crater analysis or soundsensing) and reflect a much greater activity takingplace. The artillery section could be removed priorto an enemy attack and still have caused theenemy to move his combat forces off in aharmless direction.

0 FM 902, page 23.FM 1005, page 93.



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RELIEF TCONTINUE THEATTACK

RELIEF TOCONTINUETHE ATTACK

A relief to continue theattack is cond ucted tobring fresh troops forwardto continue offensiveoperations. It will most

often be a forward passage of lines or an arearelief. Reliefs to continue the at tack are avoidedif at all possible. Any pause in the attack toarrange passage points and Signals, exchangeintelligence information, fire support plans A-10sdue at 1410 on 34.60), the f ire support coordinatorand other liaison officers, will be detrimentalsince forward momentum is likely to be lost. Inoffensive operations momentum is paramount.Once advancing units have broken through theinitia l defensive belt, resistance is lighter and thedamage done to the enemy s combat units,command and control, morale and logisticsaccelerates with every mile. If the momentum canbe maintained the enemy will be unable to predictthe route and speed of the attacking force withenough accuracy and responsiveness toestablish blocking positions. Neverthelesssituations will exist where the unit in contact is nolonger combat effective and must be replaced. Inthis relief to continue the attack every minute iscrucial. A successful forward passage of lineshere probably will mean the difference between

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maintaining the attack or moving into thedefense.A forward passage of lines is similar to a reliefin place except that speed is so critical in theformer and concealment of intentions may beimportant in the latter. The key factor in planningand conducting the passage of lines for relief tocontinue the attack is the unrelenting need tomaintain the momentum.Army Aviation in the Relief to Continue the Attack

Assault helicopters should be employed tomove the ground commander s staff to the leadunit in contact in order to make the necessarycoordination prior to the arrival of their combatforces. The helicopters should probably stand byat a laager position to the rear to return thecommander and staff to their unit on request.Assau It assets cou Id also bri ng d ismou ntedtroops forward to expedite the changeover.

Attack helicopters can serve a very importantfunction by holding the enemy at bay while therelief takes place. If things go well, the attackhel icopters may be able to mass enoughfirepowerto keep the enemy withdrawing so thatafter the relief is complete the new ground unitcan catch up to the attack helicopters and resumethe advance. This may be an occasion when thecommander would opt to employ all of his attackhelicopters at once. Such a decision would, ofcourse, make them unavailable for hours butemployed at this cri tical time they would probablymake the diffference between continuing theattack and going into defensive positions.

Thi discussion of the five special purposeoffensive operations is certainly not intended tobe limiting in any respect. There are few limits tothe employment opportunities, particularly in thedeception operations.Like the other combat arms, we in Aviation haveparticular strengths and l imitations. If weunderstand the basic operations of the groundcommander we are in a much better position toadvise him of the most effective manner toemploy Ar,my Aviation. All aviators have aninherent responsibil ity to fully understandAirLand Battle doctrine if we are to win on the nextbattlefield. 4/iiiiia X

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The thoroughness of an evaluation is shown inthese three views of MSG William Staryk at farleft as he checks the AH1 S Cobra armamentsystem in C Company, 3d Aviation Battalion.

TheU SSB

I YOU ASK any aviator whohas been in Europe more than amonth to describe the UASSB, he'lltell you they are the AORSEpeople.

The U.S. Army, Europe (USAREUR) Aviation Safety and Standar-dization Board, better known as theUASSB, is often identified by themost visible of its many duties; theresponsibility for USAREUR-Ievel

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Watchdog orUS REURAviationMajor Paul E Murtha

USAREUR Aviation Safety andStandardization Board

APO New York

evaluations of Army Aviation unitsthroughout Europe and the MiddleEast. A closer look at the 'Boardwill more fully explain its missionand responsibilities.

Situated on a small Army postnear Schwabisch Hall, Germany, theUASSB functions as the field agencyfor the USAREUR Aviation Office.A parallel agency to Directorate ofEvaluation and Standardization

(DES) located at Ft. Rucker, AL, theUASSB serves as an integral part ofthe Army Standardization Program.The unique aspect of the UASSB sthat while its goals are support ive ofthose of DES, its function is exclusively in support of theUSAREUR mission.

The UASSB began in 1955 as asmall Aviation training detachmentsituated in Echterdigan, Germany,



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designed to support 7th Army Aviation training. Its first mission, statedin General Order Number 20, was tokeep the operational readiness ofnew pilots and mechanics at toppeak. As post-Korean War ArmyAviation activities increased, so didthe Board's duty requirements fortraining the European-uniqueaspects of flying. The detachmentsoon found itself as the 7th ArmyTrainer Board for new Aviationequipment and procedures.

As the scope of its missionbroadened through the next 10 yearsso did the Board's assets. From aninitial strength of 27 the Board'spopulation reached, by late 1955,290 men and 58 fixed and rotarywing aircraft. Unit missions included aformalized evaluation activity, instructor pilot/instrument flight examiner training, a USAREUR Aviation orientation course and a specificmission, in 1966, to train 100 initialentry pilots. This mission continueduntil 97 when all Army initial entry training reverted to the continental United States. A year later, theunit was restructured and assumed ahost of new USAREUR-peculiarmissions, all designed to improvesafety awareness and provide standardization of ll facets of USAREURAviation. Since then, the Board hascontinued to increase its role inUSAREUR and, with the establishment of the Aviation OperationalReadiness and Safety Evaluation(AORSE)in 1975, stabilized itself asthe action arm of the USAREURAviation officer.The Board, commanded by a lieutenant colonel, is comprised of threeprimary branches and an operationssection to bind the three togetheradministratively.The Evaluation Branch, headedby a major, provides evaluation support to 78 separate Aviation units inEurope and the Mideast and is completely self-contained. Evaluationscover Aviation training; flightoperations; maintenance; armament; petroleum, oil and lubricants(POL); safety; and Aviation life sup-

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port equipment. In addition, theUASSB reviews several special interest areas which allow evaluationsto be tailored to a particular unit orsituation.The bread and butter of theEvaluation Branch is the AORSE. t

is a complete periodic evaluation ofan Aviation unit conducted on anI8-month cycle.Because the European environment allows little flexibility in majortraining area time or gunnery rangeavailability, it is imperative that theAORSE be scheduled well in advance. The Evaluation Branch chiefwill call on a unit commander 6months before the opening of his4-month window surrounding aperiod 8 months from the unit'sprevious AORSE. The unit commander will select the evaluationdate himself and minimize lost training time. The actual conduct of theAORSE involves as much training asit does evaluating, and units oftenuse this period to qualify potentialinstructor pilots or to receive instruction concerning new equipment andprocedures.The Evaluation Branch also provides qualification support for

maintenance test pilots and maintenance test pilot evaluators. In addition it operates a mobile POLassistance team which travelsthroughout USAREUR instructingfield and garrison dispensing techniques, storage, quality assuranceand package products procedures.The USAREUR Aviation life support equipment (ALSE) evaluator,another member of the EvaluationBranch, is responsible for providingALSE evaluation support. However,when he is not combing through unitALSE equipment rooms he is theprimary instructor of a quarterlyUSAREUR-level 3-day courseoriented toward unit ALSE technicians. The instruction reviews ALSEprocedures, discusses USAREURunique ALSE supply problems, andprovides a sounding board forALSE technicians and officers inEurope.Also located under the EvaluationBranch banner is the USAREURAviation safety evaluator. In addition to his primary duty of inspection, this officer provides USAREUR with its support for surveys ofproposed and existing helipads andteaches a 4-day over water survival

CW4 Mike Renfroe at right gives an oral evaluation to a pilot and an instructorpilot prior to flight evaluation in A Company, 3d Aviation Battalion.

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CW4 Rick Davis in these two views on thestep o an AH1 S Cobra evaluates crashrescue procedures with German firemen.

course oriented toward units withmissions that require extended overwater flight.The second functional area 0 f theUASSB is the StandardizationBranch. Also headed by a major, itprovides USAREUR with standardization instructor pilot and instructor flight examiner support and provides subject matter experts in allaspects of flight training, from newequipment introduction to combatflight techniques.One of the newest aspects of theStandardization Branch is its battlescenario training team. Duringevaluations and unit assistancevisits, standardization instructorswill review a unit's ability to accomplish one or more of its assignedmissions. All areas of the unit's combat operation from the commander's guidance to actions oncontact are examined and comprehensive feedback is provided tothe unit commander.

The Standardization Branch isalso responsible for providing newUSAREUR aviators with an initiallook at European flying. This is accomplished by a 3-day orientationcourse conducted in a classroom environment. The training involvesEurope-unique international regulations, special safety requirements,flight following procedures and allaspects of the Air Defense Iden-

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tification Zone. The instruction provides standardized training for thenew arrival and must e accomplishedbefore the aviator can be designatedas a pilot in command.In addition to its other assets, theBoard also lays claim to all syntheticflight training simulator (SFTS)facilities in USAREUR. The SFTSBranch, commanded by a captain,provides all rotary wing simulatorsupport in Europe. From its originalformal beginning as the air drivenblue canoe" of the 1950s, the SFTSactivity has grown into multifunc

tion computerized machines thatrepresent the state of the art in electronics and visual simulation. Thetotal value of simulator equipmentin Europe currently exceeds $16.7million and will rise to more than$182 million within the next 5 years.Through the CH-47 Chinook visualinstrument flight simulator at Mannheim, Germany, and its counterpartUH-l Huey instrument facility atHanau, Germany, the SFTS Branchprovides support to more than 1,800aviators in USAREUR. SFTS

Branch current expansion activitiesinclude two AH-l Cobra visual, instrument and weapons simulators;two UH-60 Black Hawk visual andinstrument simulators; and a newAH-64 Apache combat missionsimulator, all designed to be operational by fiscal year 1988. In addition to its normal functions theBranch also provides the UASSBcommander with a single point atwhich he can virtually sample everyaviator in USAREUR. The tool heuses for this is the SAFE, anacronym for the Survey of AviationField Expertise. A 20 question testgiven to aviators as they periodicallypass through SFTS facilities, theSAFE: Lasts less than 5 minutes. Can sample aviator knowledgein almost any area. Is often used to determineaviator awareness of new equip

ment, regulation changes orseasonal requirements.No names are taken and units arenever identified. After a represen-

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tative sampling has been assembled,feedback is provided to commanders,identifying trends and making trainingrecommendations.One of the most significant new

additions to the UASSB repertoireof services is a Honeywell computer.When fully functional this year, itwill provide a comprehensive database to the USAREUR Aviationcommunity for trend analysis, unitevaluation information Aviationpeculiar specialty densities and otherinformation that will allow the UASSBto provide even more services toAviation.

In addition to the activities of itsbranches the UASSB also hosts theannual USAREUR Aviation Standardization Committee Meeting; a3-day event involving more than 100leaders of the USAREUR Aviationcommunity. Issues decided upon atthis meeting are carried forward forpresentation at the annual U.S. ArmyAviation Policy Committee Meeting(see page 1 .Through its interconnecting branches and multiple functions the UASSBprovides USAREUR with its Aviation

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SSG Scott Lewis (center) evaluates OH58 Kiowa maintenance.

resource management activity. Its position in Europe as the focal point for innovative tactics and new equipmentwill ensure the Board s ability to pro-

vide a critical service to the USAREURAviation community and to maintainits status as an active partner in ArmyAviation.

MUSEUM PLEDGEUnited Technologies' Sikorsky Aircraft haspledged 100,000 to the Army Aviation Museum

Foundation to help onstru t a new museumbuilding at Ft. Rucker, AL.This pledge Is expected to provide payments tothe museum In equal Installments over a 3yearperiod. With this pledge the museum development fund reached a total of 1,392,128.69.Museum construction will begin as soon as thefinal plans ate approved by the U.S. Chief ofEngineers Office in Washington, DC

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Because of repeatedrequests for copies of thisarticle the igest iscarrying it again . t originallywas published in October 1970

TheTaetiealapnd ou

CW2 Nile I Harter Jr


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SEPTEMBER 984

DURING MY LIMITED andsomewhat trying career as an Armyaviator, I ve learned, like manybefore me, that the best source ofinformation is the grapevine,better known as the chain of command. Information flows fromSenior aviator to student pilot andback again in a never-ending streamof knowledge. All aviators encounter and relate many problemsdaily, some of which are specificallyrelated to a particular aircraft classand type, and others which pertain toAviation particulars that everypilot is likely to experience sometime during his or her career. Having been recently counseled andenlightened on one of those socalled common problems by aSenior aviator, I would like to sharemy findings with fellow aviatorsand make my contribution to thatvaluable grapevine.Most publications used for instrument flight and radio navigationare not only designed for quickreference but are also physicallysmall and easy to use in the cockpit.Most charts used for instrumentflight come pre folded for systematicuse in a limited-space compartment.But, what about visual flight publications and more specificallycharts used in a tactical or less formal situation that an aviator mightencounter while flying missions outside the continental United States?How about the aviator who mustnavigate by reference to a tactical orgeographical type chart using thepilotage method? He must be, asthey say, outside as well as insidethe cockpit with his head on a goodswivel using an unfolded x 40inch, 1 50,000 scale tactical chartwadded or stuffed in his lap in aalready cluttered cockpit. Howmany ways do you know of foldinga chart for quick and easy reference,small enough for storage in thepocket of your flight suit and efficient enough to provide an excellenttool for visual navigation?

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c n

P AN AM CLIPPER 759, aBoeing 727, took off at 4:07p.m. op9 July 1982 fromMoisant International Airport inNew Orleans. The airliner madewhat appeared to be a normalliftoff and initial climb out.Seconds later it had crashed into aresidential area, killing all 145people on board and 8 others onthe ground.The 45-year-old captain hadlogged 11,727 hours of flight time,almost all of it in the B-727. (Hisflight officer was similarlyqualified on the aircraft.) He wasaware that low-level wind shearalerts were occurring periodically

around the airport but theNational Transportation SafetyBoard (NTSB) concluded that hisdecision to take off was reasonablebased on the weather informationsupplied by his company and airtraffic control personnel.VVhat happened in the fewminutes that elapsed between thetime that decision was made andthe large aircraft slowly camedown as if a giant hand werepressing it out of the sky?Apparently at an altitude between100 and 150 feet, Clipper 759encountered a micro burst-inducedwind shear. The plane began itsinexorable descent, struck a tree,and crashed.

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S ear I ) ) ~u s lil S fETY liTIar l rr r

Meteorologists have longunderstood the wind shear foundin gust fronts, warm and cold airmass fronts, mountain waves, lowlevel jet streams, gravity waves,terrain-induced turbulence, andseabreeze fronts. Such wind shearscan be predicted-usually farenough in advance to diminishtheir hazard to aviation.Much less understood and moredifficult to predict are low-levelwind shears of the typeencountered at New Orleans. Thissame type of low-level wind shearfigured in the crash of EasternAirlines Flight 66 at JFKInternational Airport in New YorkCity in 1975. The jet, which waspreparing to land, encounteredstrong wind shear and crashedkilling 113 people. There had beenno gust front preceding this windshear and aircraft moving ahead ofFlight 66 had encountered windshear of less force or none at all.Dr. Theodore Fujita, aprominent meteorologist at theUniversity of Chicago,reconstructed the meteorologicaldata from this accident. Heconcluded that somethunderstorms produce violentdownbursts which may descend towithin 300 feet of the surface orlower before they burst outwardsinto winds with velocity of 100

knots or more. Dr. Fujita coinedthe term microburst to describethe downburst and outbursts ofthese air currents which arenormally of small size 1 to 3 mileslaterally) and of short duration 5minutes or less). The lateral windshear produced by such amicro burst could mean a switchfrom a headwind to a tailwind of asmuch as 50 knots.Congressional concern following the Pan m crash inNew Orleans led to legislationproviding for FAA to enter into anagreement with the NationalAcademy of Sciences (NAS) tostudy and assess the hazards oflow-altitude wind shear on aircraftduring the critical takeoff.andlanding stages of flight. TheNational Research Councilcommittee described wind shear asan infrequent but highlysignificant hazard. Thecommittee found that Althoughthe hazards of wind shear tohelicopters could be large, thereare insufficient statistics todetermine the extent of theproblem. The lack of reliablestatistical data on frequency ofoccurrence of wind shear andrelated accidents and the differinginterpretations and definitions ofwind shear may contribute to alack of appreciation among pilots,



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/ ISTRONG DOWNDRAFT\ \ \ \ I \I \ \ \ 1 \ \INCREASINGI J \ \ NCREASINGHEADWIND TAILWINDI \/ / \ ",-"

/ \ ,. ; / , - - - ;o 0

FIGURE 1: Schematic representation oftakeoff accident in a microburst situation. The aircraft firs t encounters a headwind and experiences increasing performance. This is followed in short succession by a downdraft and a strong tai Iwindboth causing serious performance losspossibly resulting in a crash.air traffic controllers, and aircraftoperations personnel of theseriousness of this hazard to safeflight operations_When the FAA reviewed 59,000NTSB reports of aircraft accidentsor incidents, occurring from 1964through 1975, 25 cases wereidentified involving large aircraft(12,500 pounds or more) in whichlow-altitude wind shear could havebeen a contributing factor _Ofthese 25 cases, 23 occurred duringapproach or landing. Theremaining two occurred duringtakeoff.In 27 accidents or incidentsoccurring in the United States from1964 to 1982, attributed to lowaltitude wind shear, 49 peopledied and 206 were injured.The nature of the problemMicrobursts may develop duringthunderstorms but they aren'talways present even during anintense storm. Like thunderstormsthey tend to happen most oftenbetween noon and midnight. Theycan occur beneath any convectivecloud and they develop in familiesof two or more. There are twotypes of microbursts. n dryeratmospheres, virga (streaks ofevaporating precipitation) may beseen. As precipitation falling fromconvective clouds evaporates, thedowndraft is further cooled

SEPTEMBER 1984

causing it to accelerate. Virgavirtually assures that a fast-movingdowndraft exists.A wet microburst is oftenaccompanied by heavy rainfall.While wind shear is apparently notrelated to rainfall intensity, morestudy is needed on the effects ofheavy rain on aircraft aerodynamiccharacteristics.Aircraft passing through thecenter of a microburst mayexperience an abrupt change inwind speed and or direction. Therapid change from a head wind to atail wind, which may also occur ina strong downdraft, affects lift andaltitude and is particularlyhazardous to an aircraft which islanding or taking off (figure 1).

The effect wind shear can have,particularly on large aircraft, isdemonstrated by the fact that theone in New Orleans was rated asmedium intensity The strongestmicroburst documented occurredin August of 983 at AndrewsAFB, MD. I t contained 84-knotwinds followed by 130 plus knotson the opposite side-a totaldifferential of more than 210knots_History of the phenomenonNearly 40 years agothunderstorm outflow and theaccompanying downdrafts whichnow may be referred to asdownbursts or microbursts wereidentified by the ThunderstormProject.In 97 FAA initiated a programto work on the problem of windshear in coordination with otherorganizations working in the field.Analysis of winds encountered byEastern Air Lines Flight 66 at JFKin 975 resulted in more study ofsuch violent downbursts and led toincreased efforts toward detectionand communication of warnings topilots of this hazard. Both groundbased and airborneinstrumentation detection werepart of that effort.A wind shear detection-systemcalled Low-Level Wind Shear Alert

System (LL WSAS) (figure 2) wasdeveloped in 1976. LLWSASground-level sensors to measurewind velocity are already in use at59 major airports with 5additional units scheduled forinstallation by 985 (table 1).

FAA, National Weather Service,National Science Foundation, andNASA have sponsored detailedresearch on the nature andcharacteristics of downbursts.Project NIMROD, conducted bythe University of Chicago during1978-79, and the Joint AirportWeather Studies (JAWS) r o j tconducted in the Denver area in - 982provided importantinformation on the meteorologicalcharacteristics of wind shear. TheCommittee on Low-Altitude WindShear and Its Hazard to Aviationhas recommended that anadditional field research programto measure wind shear phenomenashould be undertaken at a humidsoutheastern location tosupplement research done in thesemi-wet north-central midwesternUnited States and high, drymidwestern plains.DetectionLLWSAS is the only operationalmeans currently in use fordetecting wind shear. I t has several

FIGURE 2: Low-Level Wind Shear Aler tSystemSource: FAA. 1983

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limitations, including: The system cannot measurewinds above the sensors on theground. This may not be a bigproblem for gust fronts or seabreezes, but it limits the detectionof wind shear that may not bepresent at the surface. There are temporal and spatialresolution indications that maypresent serious problems fordetecting the smallest-scale events.Although LLWSAS sensors arelocated an average of about 2 milesbetween the centerfield and remotesites, the effective wind shearresolution is near 4 miles becauseof the long averaging period at thecenterfield site. Likewise, thetemporal resolution iscompromised by the longaveraging at the centerfield site; abrief high-wind encounter atcenterfield would probably not beidentified. This effectivelyeliminates the centerfield site as ahigh-resolution wind shear sensor. Surface wind events outside ofthe perimeter of the anemometerfield would not be detected. Vertical wind motions are notsensed directly; only horizontalones are detected, and these, ofcourse, may have been initiated bydowndrafts. Sensors do not directlymeasure wind along flight pathsand are thus susceptible toreporting events that may notreflect wind shear (or lack of one)on an airplane s flight path.Improvements to the LL WSASare being made at Moisant. Risksfrom low-altitude wind shear canbe reduced by improving the otherexisting systems. The improvedLLWSAS should eventually beinstalled at all of the 53 highdensity airports with terminalautomation systems where there isa likelihood of occurrence of windshears.What the future holdsAn appropriately-designed,pulsed Doppler radar can detecttornadoes, downbursts,

2

micro bursts, gust fronts, solitarywaves, and sea-breeze fronts. Thecost of such multiple Dopplerradar systems, however, makes itunlikely that they will becomeoperational at airports in the nearfuture.

Utilization of highly automated,ground-based terminal Dopplerradar offers considerabie hope. Asingle Doppler radar located awayfrom an airport can effectivelydetect and quantify manyhazardous phenomena over theairport and would do much todetect all forms of wind shear andprovide warning to pilots.The FAA has proposed that anunmanned Doppler terminal radarbe dedicated to the effectivedetection of hazards to aviation.The development of such aprogram, however, should not beallowed to interfere withdevelopment of Next GenerationRadar (NEXRAD). One of theproblems which will have to besolved before such a terminal radarcan be effective is automation ofinformation from the high scanrates necessary for microburstdetection and notification.NEXRAD

An advanced pulsed Dopplerweather radar installation canprovide weather information forranges exceeding 200 miles andheights of 60,000 feet at a rate ofonce every 3.5 minutes. t willprovide information on thelocation, severity and movement ofsuch weather phenomena astornadoes, severe thunderstorms,heavy precipitation, tropicalcyclones, hail, high wind shearsand severe turbulence.Such radar require anunrestricted view for 200 miles andthe height of their towers andantenna may eliminate anypossibility for low-altitudecoverage of terminal areas. Theirscan rate is too slow to be ofoptimal use in detecting the fastdeveloping, fast-dissipating,microburst.

WarningTo be effective a warning systemmust be capable of sensing windshear and computing suchinformation as fields of velocity.One question that must beanswered is what computations areneeded to accomplish the desiredresult. Display must be in relativelysimple and unambigious formats.Automated interpretations of datamust be supplemented bymeteorologists to resolveuncertainties and minimize falsealarms while retaining accuracy indetection. Air traffic controllersand pilots must receiveinformation needed to avoidhazardous conditions yet not beburdened with unneeded data.

ReportingMeteorological forecasts and inflight advisories can warn thatconditions are conducive togenerating downbursts and windshear. LL WSAS can detect lowaltitude wind shear near airportswhere they are installed, but it maybe a report by a pilot (PIREP) thatconfirms wind shear actuallyexists.Improvements need to be madein standardizing the format pilotsuse to report such weatherinformation. FAA is revising theAirman s Information Manual andthe handbook for controllers toinclude information on detectionand warning of low-altitude windshear.FAA is considering a system toprovide taped hazardous weatheradvisories, including low-altitudewind shear, to pilots by continuousbroadcast on a discrete frequency.Automatic transmission ofweather messages from CenterWeather Station units will improvedissemination of information onfast-developing wind shear hazardsto tower and control facilities.More information is needed onhow different aircraft respond towind shear under various pilotingtechniques and guidance andcontrol systems. This information

u s RMY VI TION DIGEST


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should lead to training for pilots toenable them to cope with windshear encounters. Attention shouldbe given to development ofguidance and control aids toimprove an aircraft's ability torecover from a wind shearencounter.Avoidance of conditions wherelow-altitude wind shear is likelyshould be stressed to aviators.However, the nature of thisweather phenomenon is such that it

can exist beneath any convectivecloud, whether thunderstorms areor are not present. Pilots should betrained to look for signs such asheavy rain, virga, turbulent andgusty conditions, roll clouds, orblowing dust and report suchconditions or encounters with lowaltitude wind shear quickly andaccurately. Despite improvementsin forecasting and detectionequipment, it may be these pilotreports that prevent another

aircraft from an encounter withsheer terror.Sources:LCDR Jo.seph F. Towers, ADeadly Disturbance, ApproachJun-JuI1984. Microbursts andMacrowinds, ' , F GeneralAviation News Nov-Dec 1983.Report of the Committee onLow-Altitude Wind Shear and ItsHazard to Aviation, NationalResearch Council, NationalAcademy of Sciences, Sep 1983.

TABLE 1: Location of Low-Level Wind Shear Alert System (LLWSAS) InstallationsIN OPERATION 59 UNITS)Albuquerque, NMAtlanta,GABaltimore, MDBirmingham, ALBoston, MABuffalo, NYCharlotte, NCChicago (O Hare), ILClnclnnatl,OHCleveland (Hopkins), OHColumbus,OHDallas/Ft. Worth, TXDayton,OHDenver,CODes Moines, IADetroit (Metro.), MIFt. Lauderdale (Int.), FLHouston (Int.), TXHouston, TXTO BE INSTALLED 51 UNITS)Albany, NYAsheville, NCAugusta,GAAustin, TXBaton Rouge, LABillings, MTBristol, TNCedar Rapids, IACharleston, SCCharleston, WVChattanooga, TNColo Spgs, COColumbia, SCColumbus, GADallas-Love, TXDaytona Beach, FLEIPaso,TXSource: FAA 1983

SEPTEMBER 1984

Indianapol is (Int.), INJackson, MSJacksonville, FLKansas City (Int.), MOKnoxville, TNLas Vegas, NVLittle Rock, ARLos Angeles, CALouisville, KYMemphis (Int.), TNMlaml FLMilwaukee, WIMinneapolis (Int.), MNMobile ALNashville, TNNew Orleans, LANew York (Kennedy) NYNew York (LaGuardia) NYNewark (Int.), NJNorfo lk, VA

Fayetteville, NCFort Smith, ARFort Myers, FLGrand Rapids, MIGreen Bay, WIGreensboro, NCGreer,SCHonolulu Oahu, HIHuntsville, ALLansing, MILexington, KYLincoln, NELubbock, TXMadison, WIMidland, TXMollne ILMonroe, LA

Oklahoma City, OKOmaha, NEOrlando (Int.), FLPhiladelphia (Int.), PAPhoenlx,AZPittsburgh (Int.), PARaleigh-Durham, NCRoanoke, VARochester, NYSt. Louis (Int.), MOSalt Lake City, UTSan Antonio, TXSanJuan, PRSarasota, F LTampa, FLTulsa, OKWashington (Dulles), VAWashington (National), VAW. Palm Beach, FLWichita, KS

Montgomery, ALPensacola, FLPeoria, rIRichmOfld, VARochester, MNSan FranciSCO, CASavannah, GAShreveport, LASioux City, IASioux Falls, SOSpringfield (Capitol), ILSpringfield, MOSyracuse, NYTallahassee,FLToledo,OHTucson,AZWindsor Locks, CT

,

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PEARL SPersonal Equipment And Rescue survival Lowdovvn

Marty Phillipo photo by SFC Edward aggett

Firestarter Aviation Survival MagnesiumThis item, national stock number (NSN) 1680-01-160-5618, is now in the supply system and requisitionsare being filled.As with all new items, familiarization and trainingneed to be accomplished. Many good products havebeen termed no good and a worthless piece ofequipment because the user of the product never hadadequate training to learn how to proper ly use it.The new fIrestarter comes packaged in a thermo sealed,clear plastic bag with instructions. The instruction sheetis unique because it is painted on synthetic paper and itis waterproof. Not only does it contain photographswith the instructions but it has surv ival tips on someitems you have that are onboard the aircraft and areavailable for use as tinder or fuel. (NOTE: f thefirestarter falls into a fire and remains there for 15minutes it will glow and burn; it will not explode if leftto burn out.)

The firestarter, very simply stated, is a bar ofmagnesium metal with a sparking insert glued and

22

swedged into one edge. The opposite edge is called theshaving edge. The upper corner has a hole in it witha ballchain through the hole.

To use it, take a pocket knife or other hard metal andon the shaving edge scrape the magnesium bar. Make apile of shavings about the size of a quarter in the centerof your tinder pile. The easiest way is to put the shavingsonto a leaf and slide the leaf under your tinder. Whenthis is completed turn the bar around to the sparking insert and scrape in a downward mot ion with your pocketknife blade or other hard metal to create sparks. Theharder and faster you scrape the more sparks you get.Direct the sparks onto the pile of magnesium shavingsthat you have put into the center of your tinder. Whenthe magnesium catches it will give a bright glow andyour tinder will start to smoke and burn and prestoyou have fire. This will work even if you have damp (notsoaking wet) materials.

f you read the instructions you will note they sayshavings. Chips of magnesium do not ignite as fast asshavings. So scrape the shaving edge of the magnesiumbar. The sparking insert side will not produce sparks ifyou' whack it with glancing blows, so scrape it, rapidly with downward motions, onto the magnesiumshavings.

Remember the basics of fire building: tinder, kindlingand fuel.Tinder: Pocket lint, birds nest, paper (if you must useyour instruction sheet remember to read it first, therewill be no second chance).Kindling: Small twigs, wood chips.Fuel: Small branches, squaw wood, these are thedead limbs still on the tree, high off the ground. Theseare usually dry and will burn fast and make good charcoal. A word of caution, if you are using aircraft fuel beextremely careful , particularly with gasoline, the fumesare extremely volatile. Jet fuel will ignite a lot slower,but be careful.Building a fire from wood takes time, don't be impatient. Star t small and work up to big. During damp, wetand snowy weather, it will take a longer time and morepatience to build a fire. Be patient



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Inertia Reel AssemblyEXPEDITE ACTION Subject inertia reel, NSN

1680-00-775-4182, is used as a part of the Aviation lifesupport equipment ALSE) on all types/ models/ seriesof AH-1, UH-1, CH-47 and OH-58 aircraft. It wasdetermined in a Value Engineering Change Proposalthat this inertia reel can be economically repaired atdepot level. We need your assistance to establish areturn program so that the reel repai r program can bepromptly started and sustained. This action willtranslate into an increased readiness position for you.As you remove and replace the inertia reel assemblies,please return the unserviceable reels to:

CommanderSharpe Army DepotLathrop, CA 95330RIC AQ5, W62G2T

Point of contact for this action is Margaret LaRue orJames Alexander, DRSAV-SAIA, AUTOVON 693-3809.ALSE Specialist/Technician Career MilitaryOccupational Specialist

COBRO Corporation recently completed its reportTR9-206, which identifies and supports the need forALSE career field military occupational specialties. Wewill keep you apprised of developments in this area. Westrongly support the need of ALSE military occupational specialties.USAREUR ALSE Chief

CW2 Larry Robinson has replaced CW2 CharlesChuck Gibson as the U.S Army, Europe USAREUR)

ALSE officer and focal point. Larry is going to havesome awful big shoes to fill as did Chuck when hereplaced Dave Klindt, but with all of us and the usersgiving him maximum support, his job will be madesomewhat easier. Also, with the complete support ofLieutenant Colonel Blair K Blacker, USAREUR Aviation safety and standardization officer, the task willcontinue to be given full attention and support. CW2Robinson will continue in the shoes of Chuck Gibsonduring the Aviation safety and standardization andALSE visits. f we can be of any assistance, please let us

know. PEARL stands by ready to help wherever andwhenever possible.Screw-In Flares

I could not believe my ears when I was alerted to thefact that the screw in type flares are still in some survivalvests and are still being issued to users in the field. Action should be immediately taken to purge these fromthe inventory. We are in contact with the ArmamentsCommand and have asked them to take appropriate action to make available only the proper model flareNSN 1370-00-490-7362, L119 should be used. Referenceis made to the PEARL article in the August 1983 issue ofA viation Digest and FLIGHTFAX, Volume 10,Number 14,20 January 1982. Know the problems, andchances of creating other problems will diminish. Alsobe aware that you should not keep them in your cartrunk. A recent incident still being investigated)occurred when a flare went off in the trunk of anautomobile. We feel that this was caused by slammingthe trunk lid down on the survival vest, but WE ARENOT SURE. Treat all ALSE as if your life depended onit. Someday t might.

PRC-90 Survival RadiosActions required to get well and resolve the

shortages of the PRC-90 survival radios have beenaddressed and we will all benefit by this action.

The Aviation Logistics School, Ft. Eustis, VA, hasthe proponency for Field Manual FM) 55-405,Aviation Life Support Equipment. Thesemaintenance of ALSE FMs will be published in sixvolumes. Volume I will provide general informationon management areas. Volumes II through VI willprovide consolidated and updated information onconfigurations, applications, maintenance andpackaging of all ALSE presently contained innumerous publications and directives. Thecoordinating draft for Volume I will be distributedworldwide in September 1985. Point of contact isMajor Strazzini, AUTOVON 927-5880.

The ALSE system upgrade move is on. Become apart of it to ensure the Army's finest will have ALSEat its best.

If you have a question about personal equipment or rescue/survival gear write PEARL AMC Project Officer ATTN:DRCPO-ALSE; 4300 oodfellow Blvd. St. Louis O 63120-1798 or call AUTOVON 693-1218/9 orCommerciaI314-263-1218/9.

SEPTEMBER 984 23


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irectorate ofEvaluation StandardizationR PORT TO THE FIEL VI TIONST ND RDIZ TION

Night VisionGogglesTrainingand Operations

CHANGES CHANGES, changes, why? Nightvision goggles (NVG) have been a part of training andstandardization since 1977 The changes in policies andprocedures may have appeared to be knee jerks from anunsatisfactory accident rate. True to a point, however,other factors also have contributed to change.

On close examination qualification training revealedserious shortfalls when related to combat employmentof NVGs. Qualification training based on emergencyprocedures (low level autos) and airfield traffic patterns (90 knots/300 feet above ground level) did notprepare the aircrews to meet the demanding modes ofterrain flight, a requirement for combat effectiveness.Studies revealed 80 percent of the training was conducted in the traffic pattern or runway environment.NVG mishaps, however, were occurring in the terrainflight mode 90 percent of the time. f aircrews are tosurvive in the fighting environment, we must train andqualify in that environment.

The U.S. Army Aviation Center, Ft. Rucker, ALmoved to correct this training shortcoming byredesigning qualification training for all residentcourses with emphasis being placed on terrain flighttasks. All initial entry rotary wing nightlNVG pro-

4

grams of instruction reflect this change.Mishap rates and training deficiencies were not theonly factors affecting change. Concern from command

at all levels surfaced the need for a night vision goggles symposium to be held at the Aviation Center. Theworkshop was designed for major Army commands(MACOMs) to send a representative and the Directorate of Evaluation and Standardization (DES) wouldsponsor and chair the agenda. The goal of theworkshop was to identify problem areas associatedwith NVG flight and jointly attempt to resolve them.The ultimate goal was to reduce the mishap rateassociated with NVG flight. This workshop wasplanned to convene 6 to 10 February 1984.During the interim something was needed to arrest themishap rate. The U.S. Army Safety Center repeatedlynoted during investigations of NVG mishaps that excessivespeed for flight conditions was one of many contributingfactors. Conditions that affected NVG flight were: ceilingand visibility, available ambient light, available contrast,aircrew proficiency, limited field of view, aircraft com

patibility with NVG, artificial lighting, terrain over whichflight is conducted, etc. Department of the Army (DA) withconsideration of the Safety Center s fmdings, directed in



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in December of 1983 that NVG flight would not beconducted unless ambient light levels were such thatthe moon was 30 degrees above the horizon and 23percent illuminated or artificial lights (pink filters) wereused. During January 1984 additional guidance andclarification was published by DA based on input fromthe Aviation Center's restricting airspeeds for variou'smodes of flight. These were temporary measures toprevent night vision goggles mishaps, pending theNVG workshop and recommendations from thatmeeting. The ambient light and airspeed restrictionswere an attempt to slow the aircrews down thusproviding more time to avoid obstacles. Considerationalso was given to the fact that moon elevation andpercent illumination do not always mean good ambientlight. However, it should be noted that technologyhasn t provided us with a means of accuratelymeasuring ambient light for all situations. Safety wasthe prime consideration at this point.On 6 February 1984 the night vision gogglesworkshop convened. All MACOMs were representedand a host of problem areas became evident early on.During this week a multitude of problems and recommendations for solving them were discussed andrediscussed.Subject areas ranged from aircraft modifications,NVG currency, unit trainers, available training areas,selected tasks iterations, pilot in command policy,NVG maintenance, cut-away modifications, aircrewtraining manual (ATM) guidance, day filter training,DA restrictive guidance, illumination tables, flyinghour programs, mission training, supply channels, etc.Although many of the problem areas were above thelevel of correction possible by the workshop, outstandingsuggestions and recommendations were prepared at theconclusion of the workshop. The training and standardization problems were assigned to DES to correct in theforthcoming ATM series During the week that followed amessage compiled of all the issues addressed and additional areas was submitted by the Aviation Center. Thismessage was then disseminated Armywide for additional suggestions from all MACOMs.DES, as an attempt to develop a centralized pointof contact (POC) for NVG initiatives Armywide,formed an NVG cell with representatives for each aircraft (phone numbers, POCs, FLIGHTFAX, Volume12, #28).

DES welcomes your inquiries and requests to focus attentionon an area of major importance Write to us at: CommanderU.S. Army Aviation Center ATTN: ATZQES Ft. Rucker AL

SEPTEMBER 984

The first week of March 1984 all responses werereceived at DES, and the responses were compiled withconsideration and compromises based on the MACOMresponses and rational for their responses. Thissemifinal message with recommendations for conducting NVG flight was then forwarded to DA for consideration and Armywide distribution.

On 29 April 1984, a meeting with all MACOMrepresentatives took place at the Pentagon to finalizepolicy and regulations associated with Army flight withnight vision goggles. At the conclusion all areas hadbeen readdressed and finalized with all MACOMs approving. Night vision goggles flight by this time wasconsidered as both a mission enhancement capabilityand a safety of flight issue. Problem areas unresolvedby the workshop received utmost attention, andpositive steps were achieved at correcting them in thenear future.

Aircraft compatibility with cut-away andNIAVS-6 NVG is receiving a higher priority than inthe past under the Product Improvement Program.Funds are now becoming available for correcting theseproblem areas.NVG and mission-ready aircrews are now a factorin the unit readiness report, a must in figuring andjustifying additional hours for the flying hour program. The DA message dated 25 June 1984 whichsuperseded the message of 31 May 1984, is the overallsum of these efforts to reduce the mishap rate andbalance safety with mission accomplishment. Thismessage supersedes guidance from December 1983 andJanuary 1984. During development of this guidance,all attempts were made to encourage user input, andcareful consideration was granted to that input. Yourcooperation in smoothly employing these changes goesa long way in further enhancing safety and combatreadiness.The door is never closed to your suggestions or ideasfor improving safety or readiness. NVG terrain flightin an Army aircraft is still the most demanding modeof flight known. We, as Army aviators, will do it professionally or not at allNOTE: Future reports will address current updating. and upgrading of aircraft modifications for NVGcompatibility.

36362-5000; or call us at AUTOVON 558-3504, FTS 533-3504 orCommercial 205-255-3504. After duty hours call Ft. RuckerHotline AUTOVON 558-6487 or 2( 255-6487 and leave a message.

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Personnel Changes/MILPERCENChange is a way of life in the military and during thepast several months a considerable number of ouraviators h ~ v moved on to new challenges. Shiftinggears and heading off into new directions are the following aviators:

COL Tom Denney - Plans, Programs and AnalysisDivision to the U.S. ArmySafety Center, Ft. Rucker, ALCOL Robert Wolf - Colonel's Assignments to theOffice of the InspectorGeneral at INSCOMLTC (P) Ron Adams - Aviation Branch Chief to

the National DefenseUniversity, Ft. McNair,Washington, DCLTC Bob Vandel- Aviation Plans and Programs tothe Federal AviationAdministrationMAJ (P) Joe Fucci - Lieutenant Colonel'sAssignments to Ft. Stewart,

GAMAJ (P) Sam DeLoach - Aviation Plans and

Programs to DCSLOGMAJ Paul Whitaker - Captain' s Assignments tothe Armed Forces StaffCollege, Norfolk, VAMAJ Steve Raho - Major's Assignments to theDistrict Recruiting Battalion,Harrisburg, P AMAJ Hank Hostetter - Aviation LogisticianAssignments to theCommand and General

Staff CollegeCW4 Ted Hall- Warrant Officer Branch to the101st Airborne Division (AASLT),Ft. Campbell, KYThe complexities of personnel management here atMILPERCEN can only be handled by individuals committed to doing the right thing for the officer and the

Army. While the Aviation community here atMILPERCEN has lost a significant number of highlyqualified Aviation administrators in recent months, wehave seasoned replacements with new ideas and vigor.

SEPTEMBER 984

Welcome aboard to the following aviators:BG (P) Charles E. Teeter - Director, Officer

Personnel ManagementLTC (P) Moses Erkins - Chief, Aviation BranchLTC Tom Garrett - Colonel's AssignmentsMAJ (P) Jim Orahood - Chief, Aviation Plans andProgramsMAJ Pat Oler - Aviation Logistician Assignments,Aviation BranchMAJ Dennis Schmidt - Major's Assignments,Aviation BranchMAJ Bob Demers - Major's Assignments,Aviation BranchCPT John Barton - Company Grade AssignmentsCPT Stan Hinds - Aviation Plans and ProgramsCPT Ray Nelson - Company Grade AssignmentsCW4 Joe Hines - Professional Development,Warrant Officer BranchCW 4 Carl Heinze - Warrant Officers Assignments

New Army Experimental Test PilotsOn 8 June 1984, four Army officers successfully completed the rigorous II -month Naval Test Pilot School atPatuxent River Naval Air Station, MD. Congratulations on a job well done to: MAJ Dennis W. Crowe,CPT John R. Martin, CPT Richard T. Savage and CPTRichard L. Vincent.Those interested in applying for the Naval Test PilotSchool, refer to DA Circular 351-82-5 for general information, prerequisites and application procedures.

CorrectionThe article entitled Career Management Field(CMF) 67 Reclassification Update , which appeared onpage 9 of the June 1984 issue of the A viation Digestwas written by SFC Cary Roberts of the Enlisted Personnel Management Directorate of MILPERCEN. The

Digest apologizes for the omission of SFC Roberts'byline.

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BR NCH

Major Julius J ZebehazyThreat Branch

Directorate of Combat DevelopmentsU S Army Aviation Center

Fort Rucker AL

SecondGeneration ntitankGuidedMissiles

Although it was initially believed that antitank guided missiles(ATGMs) did not pose any immediate threat to helicopters, recentindications are that the Soviets and Warsaw Pact countries aretraining with upgraded ATGMs for an antihelicopter role. This newdevelopment, second generation ATG Ms, increases the possibilitythat helicopters are viable targets on the modern battlefield.

w TH THE advancement in ground andhelicopter air-to-ground anti tank weapons, a more effective and efficient means for countering threat armorhas become a reality. The chilling realism however istwo-sided, particularly since the advent of Soviet secondgeneration antitank guided missiles (ATGM) such as theground-launched AT 4/Spigot and AT 5/Spandrel andthe air-launched AT-6/Spiral. As a pilot, you are probably asking yourself, Why should such a great threatto armor or ground forces be that much of a concern tome?As an Army aviator, particularly a scout or attackpilot, you pose one of the most crucial threats to Warsaw Pact formations because of your ability to seek out,find, disrupt and destroy enemy forces well before anyground engagements. In turn, threat forces are wellaware of your capabilities, and the modern battlefieldwill be filled with target acquisition means- from thehuman eye, to telescopic sites, to radar and forwardlooking infrared systems. (A typical Soviet army willhave more than 300 acquisition radars.) Once acquisition has been made, you can expect to encounter everytype of weapon system capable of reaching yourposition.Now you are asking yourself another question, Whyshould I worry about ATGMs? Well, just as you have

8

the benefit of extended range with your A TGM systems,so do the Soviets with their systems. But, you say, I'llbe moving nap-of-the-earth (NOE), and A TGMs aredesigned for air-to-ground or ground-to-ground use, sothey shouldn't pose any danger to a hovering, hidinghelicopter. ' ,

For some time the belief was, even by the experts,that ATGMs were not of immediate concern tohelicopters. Only recently, several indications have appeared where the Soviet and Warsaw Pact countries aretraining regularly with A TGMs in an anti helicopterrole. Placards are being found in vehicles to assist inengaging helicopters; also, home on helicoptermodes are found on newer non-ATOM systems. Let 'stake a closer look at the ATGMs that may be encountered and s if any questions or doubts about theirusefulness or capabilities remain. The information inthe figure is presented so you can make a comparison ofthe information currently available on the secondgeneration systems.

t is common knowledge that the Soviets do notdiscard their old systems or equipment when newerfollow-on developments are made. This simply meansthat the battlefield will be filled with every conceivableweapon they can devise. This does not suggest thatnewer, more efficient and more reliable weapons are not



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Soviet ntitank Guided Missile CapabilitiesAT4 Spigot AT5 Spandrel ATS Spiral

Maximum range meters) 2,000 4,000 5,000Minimum range meters) 70 100 500

Time of flight sec) 11 20 UnconfirmedVelocity m/sec) 185 200 Unconfirmed

Warhead Heat Heat HeatArmor penetration RHA) 500-600 500-600 600-700SACLOS/RadioGuidance SACLOS IWire SACLOS/Wi re FrequencyLaunch platform Manpack, BMP,BMD BRDM-2First round hitprobab ility Greater than 90

* Rolled homogen ous armor* *Semiautomatic com mand to line of sight

fielded as quickly as possible. In an earlier threat article(April 1982, A viation Digest , A TGMs were addressedas both first and second generation. In just 2 short years,extensive modernization and upgrading of old ATGMsystems has taken place.The AT-4/Spigot is rapidly replacing the inaccurate,slower flying, and man-portable AT-3A1Sagger and isbeing used to supplement the AT-5/Spandrel on theBRDM-2. (A mixof AT-4 and AT-5 is possible with theBRDM-2 configuration.)The AT 5 has largely replaced the singular and multiple vehicle-mounted AT -2/Swatter and AT-3/Saggermissile systems with frontline Soviet units. The AT-5has been assessed as being equivalent to the U.S. TOW(tube-launched, optically-tracked, wire-guided) missileand is configured with five launch tubes with an internalvehicle rearm capability.The AT-6 Spiral has been given a formidable launchplatform-the Mi-8 Hip-E and the Mi-24 Hind-E. TheAT-6 which replaces the AT-2C/Swatter on earlier Hipand Hind versions is the fastest known ATGM in theworld (as fast as the SA-7 Grail). There also are strong

SEPTEMBER 1984

BRDM-2, BMP, Mi-8Hip-E,BMD Mi-24 Hind-EGreater than 90 Greater than 90

beliefs that the Hind-E will carry more than four AT-6missiles at one time (most common mix), since the aircraft does have the wing-mount capability for additional missiles.As tanks and helicopters continue to improve, so toowill the weapons for countering them. Second generation ATGMs are able to defeat any present day armor.You have read about a Soviet capability that will befound in great numbers on the modern battlefield, andit should be evident. ..helicopters can becomejair gameto A T M gunners. One more important point toremember is you have to be seen to be targeted. Just asyou may find difficulty in acquiring targets, threat gunners with their SACLOS systems also will have difficulty.The value of and strict adherence to NOE flight cannot be overemphasized. A first round hit probability ofmore than 90 percent does not allow much margin forerror.This article was meant to make you more a ware 0 f theSoviet threat. You should give a lot of thought to thetactical training needed to increase your effectiveness onthe modern battlefield. There are means of defeating,

9


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Second Generation AntitankGuided Missiles.

countering and evading A TGMs as w ll as other antihelicopter weapons; however, the l v l of training youallow yourself to achieve may be your only means ofcompleting your mission. True, there are many morethreat systems to be concerned with, such as air-toair missiles and tank main guns that are capable ofrepeated hits on a fast-moving helicopter within thetank's maximum effective range. But remember, with alarge number of vehicle- and air-mounted ATGMs andthe likelihood that Soviet systems such as the Hind-E

and BRDM-2 will have missions more in line withcountering our armor and any system that may countertheir tanks, the probability of being engaged by A TGMsis very high. Also, keep in mind one of the Soviet's common tactics-massing fires.Second generation A TGMs are only one of the continuing developments from Soviet and Warsaw Pactcountries. Much of the information within this articlewas obtained from data contained in the draft FM100-2 series, The Soviet Army to be published thisyear, which should become part of every Aviationunit's must read and know file. The moreknowledgeable you become about a probable enemyand his equipment, the more likely you c n survive tobecome an Army asset capable of fighting (flying)another day. j j f ; .

30

AT5 Spandrel lef t and above).

AT4 Spigot.

u.S. ARMY AVIATION DIGEST


33/48

HE OH58 KIOWA aircraftand crew were engaged in asingle ship aeroscout missionsearching for an air defense art il lery ADA) site. The aircraftwas being operated at 2,850pounds and with a left crosswindof 5 knots. The pilot was hovering the aircraft along a narrowdirt road at an altitude about 10feet above 50 foot trees. As theaircraft slowed below effectivetranslational l ift ETL), the aircraft began a slow, uncommandedright yaw. The pilot immediatelydiagnosed the problem as loss

SEPTEMBER 1984

58OllOF T IL AOTOA

EFFECTIVENEJIWHY ITOCCURJ

A recent study to isolate the cause of loss oftail rotor effectiveness LTE) and to recommendcorrective actions was conducted by a JointSpecial Study Group. The study revealed LTE isnot synonymous with only OH58 helicopters, butcan occur in any single rotor helicopter.Specifically, LTE is produced by wind velocities,tail rotor thrust variations and tailwinds. This article identifies 15 maneuvers which cansignificantly increase the possibilit y of LTE and3 product Improvements with proven capabilit iesto avoid the occurrence of LTE.

Captain David M. SnellenOffice of TRADOC System Manager

for Scout HelicoptersU.S. Army Aviation Center

Fort Rucker, AL

of tail rotor effectiveness, eventhough he realized none of thenormal conditions that producethis condition existed. He immediately removed some leftpedal and maintained his collective. This caused the aircraft toyaw right at an increasing rate.

As the aircraft continued its turninto a tailwind condition, thepilot applied right forward cylicand further reduced left pedal.This allowed the turn to ac -celerate into a nose low, rollingspin. The aircraft completed oneturn after it accelerated into aspin, at which time the pilot closedthe throttle and autorotated intoa small clearing in the trees. Dur-ing the descent, both main andtail rotor blades made contactwith trees. The aircraft rolled tothe left and impacted hard on itsleft side.

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Why did this pilot crash? Thepilot s preflight planning was by thebook. He reacted with the publishedemergency procedure. The performance planning card indicated heshould have sufficient left pedal.Just what is loss of tail rotor effectiveness (L TE)? The accident investigation team said the pilot wasflying in an LTE conducive environment. What is an LTE conducive environment? Someoneneeds to find out what is going on.The Department of the Army(DA) tasked Training and DoctrineCommand (TRADOC) in May 1983to establish a TRADOC/ ArmyMateriel Development and Readiness Command (DARCOM-nowcalled Army Materiel Command)OH-58 LTE Joint Special StudyGroup (JSSG). The JSSG was giventhe mission to conduct sufficientstudies, tests and analyses to identifyand isolate the LTE phenomenon,nd to determine corrective actions.The purpose of this article is to ex

plain what LTE is and why theOH-58 is subject to this phenomenon. A summary of the testing efforts and recommendations made tothe DA staff are also included.To understand LTE, the pilotmust understand the function of thetail rotor. The tail rotor s function isto counteract the torque generatedby the main rotor. On Americanmade single rotor helicopters, themain rotor rotates counterclockwise.The torque produced by the mainrotor causes the nose of thehelicopter to turn right. The tailrotor counteracts this inherent rightyaw with a thrust that pushes thenose left. Therefore, the tail rotorthrust provides directional control.Tail rotor thrust is the result of tailrotor blade pitch which is controlledby the pilot. f the tail rotorgenerates more thrust than is required to counter the main rotortorque, the helicopter will yaw to theleft; yet, if less tail rotor thrust isgenerated, the aircraft will yaw tothe right. By varying the thrustgenerated by the tail rotor , the pilot

3

can control the heading of the helicopter.In a sterile, controlled environment, for a given main rotor torquesetting, there is an exact amount oftail rotor thrust required to preventthe helicopter from yawing either leftor right. This is known as tail rotortrim thrust. However, the environment in which Army scout pilots flyis neither sterile nor controlled. Theyare continuously subjected to constantly changing wind directions andvelocities. The required tail rotorthrust in actual flight is modified bythe effects of the wind. f an uncommanded right yaw occurs in flight, itmay be because the wind reduced thetail rotor effective thrust. Thewind can also dd to the tail rotorthrust. In this case, the helicopterwill react with an uncommanded leftyaw. In other words, the winds canand will cause tail rotor thrust variations to occur. Certain relative winddirections are more likely to causetail rotor thrust variations thanothers. These relative wind directions or regions form the LTE conducive environment.

The JSSG conducted extensivetesting to identify the LTE conducive regions and the effect theyhave on the aircraft . Figure 1 will beused to explain these regions. Thedata contained in figure 1 wasderived from wind tunnel tests of amodel OH-58 and serves to illustratethe yaw moment (static stability (seeField Manual 1-203, paragraph5 49 characteristics of the OH-58for variations of wind azimuth at aconstant wind velocity. In layman slanguage, for the pilot to maintain aconstant heading at a given relativewind direction, he must maintain thetail rotor thrust at a value equal tothe trim thrust. Thus, if the trace ismoving downward (positive stability),the pilot must decrease the left pedalinput or the helicopter will yaw to theleft. When the trace is moving upward (negative stability), the pilotmust add left pedal or the aircraftwill yaw to the right. The steepnessof the slope indicates how fast thepilot must react with corrective

pedal. The magnitude of the variation is an indicator of how much corrective pedal would have to be applied. The bottom axis is the direction of the wind relative to the noseof the aircraft. The main rotor wasproducing lift and the tail rotor wasfixed at a constant pedal setting. So,any changes in the trace can be attributed to the effects of the wind.Through flight and wind tunneltesting, the JSSG was able to identifythree distinct relative wind regionsthat either singularly or in combination can create an LTE conduciveenvironment. These wind regions areshown in figure 1.First, winds at velocities of about10 to 30 knots from the left front canblow the main rotor disc vortex intothe tail rotor. This main rotor discvortex is a circular, rotating columnof air that can be deflected into thetail rotor by the relative wind. Whenthe tail rotor comes into the presenceof the main rotor disc vortex, the tailrotor can experience a reduction ofthrust. The reduction in tail rotorthrust comes from the air flowchanges experienced at the tail rotoras the main rotor disc vortex movesacross the tail rotor disc. This thrustreduction will occur suddenly, asshown by the sharp reversal of theyaw moment at point A, figure 1.Under normal conditions, this canoccur when the relative windazimuth is between 280 and 330degrees. LTE can occur if the pilotdoes not quickly react by applyingadditional left pedal. The helicopterwill yaw to the right because of thereduced tail rotor thrust and resultant lack of trim. When operatingwithin the vicinity of this region, thepilot must be aware that the reduction in tail rotor thrust can happenquite suddenly and he must beprepared to counter that reductionwith additional left pedal input.Second, a tail rotor vortex ringstate does exist in a relative windazimuth of 210 to 330 degrees (leftcrosswind). As the inflow passesthrough the tail rotor it creates a tailrotor wash to the left. A left cross-



35/48

VortexRingState I DiscVortex

~

wind will oppose this tail rotor wash.This causes the vortex ring state toform which causes a nonuniform,unsteady inflow into the tail rotor.The net effect of the unsteady inflowis an oscillation of tail rotor thrustabout its trim value. This is whywhen the pilot is hovering a leftcrosswind, he will be m k i ~ rapidand continuous pedal movements.In actuality, the pilot is attempting tocompensate for the rapid changes intail rotor thrust. These tail rotorthrust variations can be seen at pointB figure 1. Because these tail rotorthrust variations do occur veryrapidly, LTE can occur when thepilot overcontrols the aircraft. Thepilot simply is not fast enough toreact to each variation and he will beapplying right pedal when he shouldbe applying left pedal. Remember,when the thrust being generated isless then the thrust required, thehelicopter will yaw to the right.When hovering in left crosswinds,the pilot must concentrate fully onflying the aircraft , and by smoothly

SEPTEMBER 1984

Weathercocking

FIGURE 1

thrust reduction: sharp reversalof yaw momenttail rotor thrust variations leftcrosswind)y w r te accelleration, 120-240

Wind zimuth

coordinating his pedals, not allow anuncontrolled right yaw to develop.Third, tailwinds from 120 to 240degrees, like left crosswinds, willcause a high pilot workload. Themost significant characteristic oftailwinds is that they are a yaw rateaccelerator. The region of 120 to 240degrees is actually an area offuselage static instability. f he pilotallows a right yaw to develop and thetail of the helicopter moves into thisregion, the yaw rate can acceleraterapidly. This accelerative momentcan be seen at point C, figure 1. t isimperative that the pilot maintainpositive control of the yaw rate anddevote his full attention to flying theaircraft when operating in a downwind condition.Figure 2 summarizes the LTE conducive regions when viewed fromabove. Note that the regions dooverlap and be a ware that the mostpronounced thrust variations can occur in the overlapping areas. Understand that these regions are not unique to the OH-58. To a varying

~

degree, all single rotor helicopterscan experience L TE.It has been stressed repeatedly inthis article and in the operator smanual that the pilot must concentrate fully on flying the aircraft. fthe pilot fails to detect and correctthe initial yawing rate, the situationcan rapidly get worse. Two secondsmay very well mean the differencebetween a successful mission or anaccident.

The JSSG was able to disproveseveral myths associated with LTE.Important points to remember are: The tail rotor, even with yawrates in excess of 115 degrees per second DPS), does not stall. The tail rotor on a standardOH-58 can stop a yaw rate in excessof 115 DPS if forward cylic and fullleft pedal are applied and held. In no case will the applicationof left pedal aggravate the situation. The OH-58 can be flown safelyin the terrain flight environment ifthe pilot will concentrate fully on flying the aircraft.

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~ W E T H E R C O C K I N Gl v o R ~ I T : I N G

I_IDIS VORTEX

FIGURE

The JSSG membership includedtechnical experts from the U.S.Army Aviation Center, theTRADOC System Manager forScout Helicopters (TSM-SH), theArmy Safety Center, the ReadinessProject Of

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Army Aviation Digest - Sep 1984

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