03 Aopa Collision Avoidance Article

8/8/2019 03 Aopa Collision Avoidance Article

1/12

MaintainingSeparation

Despiteimprovementsinthegeneralaviation(GA)safety

record inrecentyears, the numberofmidaircoll isions

(MACs)showsnocorresponding decline. MACscontinueto

occuraboutthirteentimesayearonaverage, oftenresulting

inmultiplefatalities. Ontheground, collisionscausedby

runwayincursionsarestillaconcernforGA. Insteadofwait-

inguntilaftertakeofftobegintheircollisionavoidancescan

pilotscanavoid arunwayincursionbyincreasingtheir

vigilanceimmediatelyafterenginestart.

Collisionavoidance, bothintheairandontheground, is

oneofthemostbasicresponsibilitiesofa pilotflyinginvisua

conditions. During primarytraining, pilotsaretaughttokeep

theireyesoutsidethecockpitand lookfortraffic. ThisSafety

Advisorgoesastep furtherand teaches pilotshowtovisually

identifypotentialcollisionthreatsandcoversprocedures

thatcanlessentheriskofanin-flightcollisionorrunway

incursion.

History ofMACs

Manyoftherulesand proceduresthatapplytoflightincon-

trolled airspacearethelegacyofMACs. In 1956, all 128

peopleaboard losttheirliveswhenaDC-7 and aLockheed

ConstellationcollidedovertheGrandCanyoninVFRcondi-

tions. Thistragedyledtopublicoutcryforthemodernization

oftheairtrafficcontrolsystem, resultinginthemoreeffec-

tivesystemthatwehavetoday. A 1978 collisionoverSan

Diegoinvo lvingaBoeing 727 and aCessna 172both

underradarcontrolcaused the deathsof144 peopleand

resultedineventighterrestrictionsonflightsinheavilytraf-

fickedareas. CongresspassedtheAirportandAirwaySafety

ExpansionActafterthe 1986 collisionofaDC-9 andasin-

gle-enginePiperoverCerritos, California, whichclaimed the

livesof82 peopleintheaircraftand 15 ontheground. The

Airportand AirwaySafetyExpansionActnowrequiresal

civilaircarrieraircrafttobeequippedwithTrafficAlertand

CollisionAvoidanceSystems(TCAS).

S A F E T Y A D V I S O ROperationsandProficiencyNo. 4

Collision AvoidanceStrategies and Tactics

Collisionavoidance,

bothintheairandontheground,is

oneofthemostbasic

responsibilitiesofa

pilotfl

ying

invis

ual

conditions.

Safe Pilots. Safe Skies www.asf.org


2/12


3/12

The positionofthesunmustalsobeconsidered. When

lowonthe hor izon, itmakesanytrafficbetweenthe

observerand thesunvery difficulttosee . Operatingin

theseconditionsrequiresextravigilance.

OpticalIllusions

Opticalillusionscanaffectwhatweseeinflight. Forexam-

ple, anaircraftataslightlyloweraltitudecomingtoward

youmaylooklikeitsaboveyouandappeartodescendas

itcomescloser. Atnight, apilotsabilitytojudgedistance

abovethegroundwhileonvisualapproachtoarunwayis

impaired. Fortunately, spottingaircraftinflightisntusually

muchofa problematnight, sincea properlyilluminated

aircraftismucheasiertosee atnightthananaircraft

operatingindaylighthours. Theexceptiontothisruleis

identif

ying

aircraft

b

elow

you

that

bl

end

in

with

lighting

on

theground.

OtherFactors

Inadditiontoatmosphericconditionsand opticalillusions,

irritantsinthe air, fatigue, age, residualalcoholinthe

bloodstream, andloweroxygenlevelscanallimpactthe

abilityofyoureyestoperformattheoptimumlevel.

Aircraft Design Considerations

The designoftheaircraftitselfcanalsohindervisibili

Windshield distortion, placementofwindowand win

shield posts, and otherstructuralelementscanaffectwha

pilotsees. Thebrainrequiresinputfrombotheyestoacc

ratelyinterpretthevisualcuesitreceives. Ifawindshie

postorotherobstructionblocksthevisionofoneeye, t

brainmaynot perceivetheobject-evenwiththeothere

providinginput. TheNTSBhasconcluded thiscould be

causalfactorinsomemidaircollisions. Ahighglareshie

canalsoblockvision, whichisespeciallyproblematicduri

climbout.

Nomatterhowgood thevisibilityisfromthecockpit,

aircrafthaveblind spots. High-wingaircrafthavereduc

visibilityofaircraftabovethem, andcanhavetheirview

trafficbloc

ked

wh

en

ma

king

turns

in

th

epatt

ern

as

t

wingisloweredinthedirectionoftheturn. Low-winga

crafthave alarge b l ind spo tbeneaththemthatm

obscureconflictingtrafficwhen descendingintothe patte

orwhileonfinalapproach. Pilotsmustrecognizeand co

pensateforvisuallimitations, whetheritsraisingawing

checkfortrafficbeforemakingaturninahigh-winga

p lane , or making shal lowS -turnswhen c l imb ing

descendinginanyaircraft.

Haze andfogcan impact theeyes ability to discern collision threats.

Safe Pilots. Safe Skies Pg. 3 www.asf.or

When scanningfor traffic, thepilot must be aware oftheblind spots

that can becreatedby aircraft design.


4/12


5/12

toeachother. Whenobserved fromthecockpit, thecon-

flictingtargetwilllooklikeasmall, stationaryspeckuntilitis

atadistancefromwhichitmaybetooclosetoavoid. This

iscalledtheblossomeffect.Ifapilotseesanaircraftthat

remainsinthesamespotinthewindshield(unless itis

directlyahead and movinginthesame direction), thereisa

high probabilitythetwoaircraftwill coll ideunless one

changestheircourse. Onceathreathasbeenidentified, its

essentialtokeeptheotheraircraftinsightuntilthethreatis

resolved.

Cockpit ResourceManagement

Effectivecockpitresourcemanagement(CRM)requiresan

efficientscan. Themore quicklyinstrumentsand gauges

canbemonitoredandinterpreted, themoretimeavailable

toscan

for

traffic

.An

exp

erim

ent

conduct

ed

with

militar

ypilotsfoundtheaveragetimeneededtoconductaneffec-

tivescanwasatotalof20 seconds 17 secondsfortheout-

sidescan, and threesecondsforthe panelscan. As demon-

strated bythemilitary pilots, considerablymoretimeshould

bedevotedtoscanningoutsidethaninside.

CRMalsoincludeseffectivemanagementofdistractions

suchas passengers, avionics, and chartmanagementtasks.

1 2 3 4 5 6 7 8

Side-to-side scanning method.

Startattheleft ofyourvisualareaand makeamethodicalsweep to the

right, pausingineachblockofviewingto focusyoureyes. Attheend of

thescan, returnto the panel.

Front-to-side scanning method.

Startatthecenterblockofyourvisualfield(center offrontwind-

shield);moveto theleft, focusingineachblockthenswing quickly

backto thecenterblockafterreachingthelastblockontheleftand

repeatthe performanceto theright.

Figure 3. BlockSystem Scan

Blossom Effect

Efficient scanningrequires effective management ofotherflight tasks

TodaysGPSreceiversareextremelycapable, buttheyare

alsopilotworkloadintensiveparticularlywhenmultip

waypointsmustbeinserted intoaflight plan. GPSreceive

should alwaysbe programmed ontheground to provid

moretimeforscanningintheair.

Phases ofFlight

Midaircollisionscanhappeninany phaseofflight. Avoi

ancestrategiesneedtobeadjustedtoreflecttheflightenv

ronmentandrisksassociatedwitheachparticularphase.

TakeoffandClimb

Nearly 11 percentofallmidaircollisionsoccur duringtakoffand climb. Ensurethatthe runwayisclearbefo

departingandlistenforotherinboundaircraft. Dontforg

tomakepositionreportsandunderstandothersreports

nontoweredairports. DuringclimboutuseshallowS-tur

orlowerthenoseoccasionallytogetabetterviewofth

area directlyinfrontoftheaircraft. Pilotscanalsotransitio

tocruise-climbspee dstogainbetterforward visibili

(althoughsomeclimbperformancewillbesacrificed).



6/12


7/12


8/12

possiblethatthepilotmaynotevenknowwhereheisif

hesunfamiliarwiththefield. Typically, incursionsbyGA

aircraftresultingo-aroundsorreduced separationbetween

conflictingtrafficratherthanaccidents.

Toreducethechancesofarunwayincursion, alwaysreview

thelayoutsofdestinationanddepartureairportsduring

yourflight planning.

Accidents

ACessna 172 andaCessna 152 collidedontherunwayat

Sarasota, Floridastoweredairport, resultinginfourfatali-

ties. AccordingtotheNTSBreport, confusioninthetower

and lackofattentioninthecockpitwerefactorsintheacci-

dent. The 15 2 had beencleared fortakeoff. The 172,

whichwasholdingshortforanintersectiondeparture, was

thenclearedontotherunway, andtaxiedrightintothepath

ofthe 152 onitstakeoffroll. Thecontrollerthoughtthe 172

hed cleared ontotheactivewastheaircraftwaitingbehind

the 152. And thoseaboard the 172 involved intheaccident

apparently didntlookfortrafficbefore proceedingontothe

activerunway. Thisaccidentunderscoresthefactthatpilots

needtomaintainconstantvigilance, whetherunderthe

controlofATC personnelornot.

TheNovember, 1996 collisionofaBeechKingAiranda

Beech 1900 inQuincy, Illinoisillustratesthepotentialcon-

sequencesofincursionsatnontowered airports. Cockpit

VoiceRecorder(CVR)tapesfromthe 1900 indicatethat

confusionand lackofattentionand communication played

prominentrolesinthisdisaster. The1900wasonastraight-

inapproachforRunway 13, andannounceditsintentions

ontheCTAF. TheKingAirannounceditwasgoingtotake-

offonRunway 4. Thecrewofthe 1900 asked iftheKing

Airwasgoingtohold untiltheylanded. However, athird

aircraftattheairport, aPiperCherokeebehind theKingAir

onRunway4, respondedthathewouldhold, andthat

transmissionwas

partiall

ybloc

ked

,appar

entl

yleading

th

e1900 crewtobelievethetransmissionwasfromtheKing

Air. The 1900 continued withitslandingastheKingAir

commenced itstakeoffroll. Theycollided attheintersection

ofthetworunways, claimingthelivesofallthoseaboard

bothaircraft.

AvoidingRunwayIncursions

Reviewtheanticipated taxiroutebeforetaxi(priorto

departure)andenroute(priortolanding).

ListencarefullytoATCinstructionsattoweredfields. The

routeyouregivenmaynotbetheoneyouexpected.

Read backalltaxiinstructions.

Ifuncertain, confirm permissiontocrossanyand allrun-

wayspriortocrossingthem.

Acquireairportdiagramsforallairports, especiallythose

withwhichyouareunfamiliar. To printfreeairport dia-

grams, gotowww.asf.org/taxi.

Ifindoubt, askfor progressivetaxiinstructions.

Lookfortrafficbeforetakingtherunway. Ensurethatno

conflictingtrafficexistsbeforebeginningthe

takeoff.

Atnontowered airportswithintersectingrunways, check

fortrafficonthecrossingrunwayaswellastheoneyou

intend tousefor departure; dothesamewhenlandingat

theseairports.



9/12


10/12Safe Pilots. Safe Skies Pg. 10 www.asf.or

Plan yourflightKnowyourroute, thefrequenciesyoullneedalongthe

way, andthe pertinentinformationforyourdestination.

Fold chartsand presetnavigationalaidstomaximizescan

time. Programyouravionics(includingGPSunits)onthe

ground tominimizeheads-downtimeintheair. Anticipate

whereyoumayfindhightraffic/highworkloadareas. Avoid

theseareasifpossibleorplanonbeingextravigilantduring

those phasesoftheflight.

EquipyourselfIfyouoperateanaircraftwithoutradiosortransponders,

considerinstallingthemtoenhanceyoursafety. Regulations

requirethataircraftequipped withtranspondersmusthave

themonduringflightincontrolledairspace.

EducatepassengersAs

part

of

your

pr

eflight

bri

efing

, explain

basic

scann ing

procedurestopassengersandhavethemassistinspotting

traffic. ExplainFAAradaradvisory procedures, sotheycan

help locatetrafficcalled byATC.

CommunicateWhenflyingincontrolled airspace, familiarizeyourselfwith

therequired communication procedures. Atnontowered

airports, beginannouncingyourpositionwhen 10 miles

out.

Use sunglassesSunglassesthatblockoutUVrayshelpprotectyourvisionand

reduceeyefatigue. Red/yellowspectrumlensesmakeiteas-

iertoseethroughhaze. Polarized lensesreduceglare, butthis

may be a detriment to spotting traffic as the glint of light

bouncingoffanaircraftisoftentheverythingthathelpsmake

itvisible.

ObserveproperproceduresUsecorrectcruisingaltitudesandtrafficpatternprocedures.

Announceyour positionatnontoweredairports. Recognize

thatnoteveryonefollowstherules.

ImproveyourvisibilityBugsorothercontaminantsonyourwindshield canblock

anaircraftfromviewand makeitmore difficulttofocus

properly. Duringclimbout, makeS-turnsforimprovedfor-

wardvisibility. Onceyouvereachedasafealtitude, use

cruise-climbairspeedstogetabetterviewoverthenose.

Scan for traffic!Usethetechniques presented inthisSafetyAdvisor(see

Page 5). Rememberto devotemoretimetoscanningfor

trafficoutsidethanscanningtheinstrumentsinside.

Use aircraft lightsInstall and use add itionallightingtohe lp other pilots

see youraircraft. Useyourlandinglightonapp roach,

departure, andclimboutespeciallywithin 10 milesofany

airport.

Collision AvoidanceChecklist

You now have theknowledge to minimize the threat ofcollisions in the air and on

theground. Use thefollowing tactics to enhance the safety ofeveryflight.


11/12Safe Pilots. Safe Skies Pg. 11 www.asf.or

Theres always something new that todays pilots need toknow. To keep up with the ever-changing world ofgeneral aviation, you need a resource that evolves with it.

At www.asf.org, the AOPA Air Safety Foundation isevolving at the speed of aviation. Log on today to take

advantage of all the FREE tools at the Internets premieraviation online safety center where there is alwayssomething new.

www.asf.orgwww.asf.org

When it comes to air safetypilots turn to one source:

When it comes to air safety,pilots turn to one source:

FREE! Available 24 Hours a Day, 7 Days a Week!

Safe Pilots. Safe Skies: Every Pilots Right Every Pilots ResponsibilitySafe Pilots. Safe Skies: Every Pilots Right Every Pilots Responsibility

The AOPA Air Safety Foundation

421 Aviation Way Frederick, MD 21701-4798

1.800.638.3101


12/12

Copyright 2006, AOPAAirSafetyFoundation421 AviationWay, Frederick, MD 21701

800/638-3101

E-mail:[email protected]

Web:www.asf.org

Publisher:BruceLandsberg

Editors:LeishaBell, BrianPeterson, JenniferStormWriter:JamesWynbrandt

Intern:BillMastick

SA15 Edition 2 8/06

EXPLOREASFS SAFETY PRODUCTS

EXPLOREASFS SAFETY PRODUCTS

Safety Advisors Safety Highlights Nall Report Videos Seminar-in-a-Box Program

421 Aviation Way Frederick, MD 21701 800/638-3101 www.asf.org

These ASF products were made possible through contributions from pilots like you.

and many more...

Documents

03 Aopa Collision Avoidance Article