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  January2007   HINDSIGHTN°5Page 31July2007The Briefing Room - Learning from Experience Effective communication is a basichuman requirement and in the aviationenvironment an essential pre-requisiteto safety.So why do we continue to getit so wrong? - and we do get it wrongabout 30%of the time.In a recent radiotelephony survey it was found that80%of RTF transmissions by pilotswere incorrect in some way.Howeverpilots are not the only ones in the com-munication process,and there aresome startling statistics from the airtraffic controllers as well:  30%of all incident events havecommunication errors,rising to50%in airport environments.  23%of all level-bust events involvecommunication errors.  40%of all runway incursions alsoinvolve communication problems.None of these statistics are surprisingwhen we realise the demand we placeon the verbal communication process,and most of us know some of the obvi-ous traps:call sign confusion,the prob-lems with native language,the use ofstandard phraseology and the increas-ing traffic and complexity leading tofrequency congestion and overload,aswell as a high percentage of technicalfailure of the communication systemitself.However,what might not be soobvious is the complexity of effectivecommunication and the aviation cul-ture which reinforces operational staffs’trust in other colleagues.The following graph indicates the mostnumerous problems,however this onlyillustrates half the story.Perhaps more importantly we shouldascertain the most serious issuescaused by these activities and the con-text in which they are likely to increasethe risk to the system.The leading events,which encompasssome of the above issues are:mis-hear-ing information over the RTF,oftencaused by incorrect pilot read-back ofinformation (but by the correct pilot)and transmission and/or recording ofincorrect information by either thepilot or controller.In all cases the prob-lems are embedded in the complexityof the communication process itself.Inorder to transfer information,both theperson sending and receiving theinformation must be able to formulate,listen,hear and interpret the messagecorrectly as well as verify the informa-tion for completeness,and at any oftheses stages things could go wrong.The most risky situation is when one ofthe parties does not identify or recog-nise an error,since then they areunable to recover from the situationthemselves.Some of these risks areembedded in the way we ascertain EFFECTIVE COMMUNICATION IN THE AVIATION ENVIRONMENT:WORK IN PROGRESS By Anne Isaac,Ph.D. Anne’s early experience in ATM and airline operation was followed by six years with the Human Factors team at EUROCONTROL,where she was associated with the development of tools and techniques to help identify human error and risky performance in the ATM environment,as well as developing the Team Resource Management (TRM) concept for European ATM.Anne now heads a team in Human Factors integration within the Division of Safety in NATS,UK.  January2007   July2007Page 32HINDSIGHTN°5The Briefing Room - Learning from Experience information from equally qualified col-leagues.We tend to ask confirmatory questionsto solve a problem when we are unsurein these situations.The example below is taken from the Danair 1008 air acci-dent at Tenerife: Co-pilot :  gosh,this is a strange hold,isn’t it? Captain :  yes,it doesn’t ............................,it doesn’t parallel the runway or any-thing. Co to Engineer :  it’s that way isn’t it? Engineer :  that is a 3 isn’t it? Co :  yes,well,the hold is going to bethere,isn’t it? Captain to Co :  did he say it was 150inbound? Co :  inbound,yeah Captain :  well,that’s....................................,I don’t like that Co :  they want us to keep going allaround,don’t they?Another very risky situation,in terms ofthe above issues,are conditional clear-ances.Conditional clearances are usedon the understanding that both partiesare assured of the message they hear.Since most of the information which isfound in the conditional clearanceinformation is standard and known byboth parties,it is very rare for one ofthe parties to question part of thiscommunication.Usually you will hearthe person receiving the message say,“Oh he must have said that,or shemust mean this”.This situation is mademore risky when the actual communi-cation is correct but incomplete.Almost all runway incursion incidentswhich involve conditional clearancesare also the result of incomplete com-munication strings.This is particularlyrisky for both parties since an incom-plete transmission is not so easy to pickup as an incorrect transmission.Another example regarding communi-cation and feedback to colleagueswithin the aviation industry is the issueof seniority and expertise.Air trafficcontrol assistants as well as cabin crew believe that it is not their place toquestion or challenge a colleague whois more qualified or in a position of sen-iority.The following example illustratesthis and had fatal consequences. On March 9th 1989,an Air Ontario Fokker F-27 was getting ready to take-off from a small airport in Northern Ontario.Take-off was delayed as the tower waited for a small private aircraft to land.It had been lost in a spring snow storm.Whilst the aircraft waited for take-off clearance,several passengers took note of the accu- mulation of snow on the wings.One of them brought it to the attention of the flight attendant,who assured him that there was nothing to worry about.Many of the aircraft’s occupants were con- cerned about the snow,but no one,including the flight attendants,thought it appropriate to say anything to the flight crew.When asked about this dur- ing the course of the investigation,the one surviving crew member,a flight attendant,stated that she did not feel it was her job to inform the pilots of poten- tial problems.She had never been trained to question an area that in her mind was clearly a pilot responsibility.Moshansky,1992. Since then both the development ofCrew and Team Resource Management  January2007   HINDSIGHTN°5Page 33July2007The Briefing Room - Learning from Experience activities have enabled clarificationand challenge to be an acceptable partof this working environment.One of the most prevalent errors in allaviation communication is informationwhich is mis-heard or not heard at all.The reasons for this are again manyand varied,which is why ICAO andNational Air Navigation ServiceProviders train their operational staff touse standard radio telephony.So whydon’t we stick to these rules? Researchwould indicate that there are severalhuman traits which make followingrules more problematic.Firstly people,even controllers,assistants,pilots andaerodrome drivers never believe theycould be involved in a serious incidentor accident.The fact that these events,compared to the number of aircraftmovements,are relatively rare,helps toperpetuate this belief.This trait is notexclusive to aviation professionals,weall believe the best when we step out-side into the hazardous world,notappreciating we could be the victim ofmany and varied serious incidents.Secondly,having developed standardphraseologies,individuals as well asCentres,Units and even NationalProviders and Airlines believe,becausethey are different,they need to applyfor an exemption or change to the rule.These changes are rarely associatedwith a study to establish the reason forthe changes and the best consequentsolutions.Again it is rare that proce-dure specialists would ask the advice ofthe human performance specialistsabout how humans process both writ-ten and spoken information.This oftenleads to the use of incorrect phraseolo-gies being delivered in the wrongorder.Some of these risky words andphrases have been identified as fol-lows:  In turn - intended sequence isunclear;  Next exit - who’s next are you refer-ring to;  Pull forward - clearance is not clear;  One hundred and eleven hundred- as in flight level;  Three digit numbers ending in zero- heading often confused withflight level;  Similar sounding letters and num-bers - B,G,C,D and 3;  Made a ...interpreted as Mayday;  Holding position interpreted ashold in position;  Climb to,two thousand - action,fol-lowed by qualifier.Many other errors are made because ofthe problems of expectancy.Becausewe use standard phraseology,we oftenexpect to hear a particular request orreply in a familiar situation.If the mes-sage we receive is distorted in someway,such as due to other noise or cutoff,it is easy to assume we heard whatwe expected to hear instead of con-firming the message.Hearing what wewant to hear,guessing at an insignifi-cant part of the spoken message,andfilling in after the fact,are common-place.We also reconstruct parts of mes-sages unintentionally - and we do sowith the utmost confidence that wehear what we actually reconstructed,not what was said.Another reason for the prevalence ofinformation which is mis-heard or notheard is associated with interruptionand distraction.Usually a verbal mes-sage or phone call will interrupt almostany activity,and by the time we realisethat this interrupting message is of lit-tle importance,it is too late to retrievethe activity we were engaged in whenthe message or phone call started.Thisresults in the two tasks,whether theywere verbal (receipt of a message) oranother action (scanning,writing)being incomplete.When two activitiescompete for our limited workingcapacity we usually end up losing allthe communication channels,and haveto start again.This problem is particularly obviouswhen working under a high task load.Task load is dependent on work load(the sheer volume and complexity oftraffic) and contextual conditions suchas:  Weather;  Experience;  Fitness;  Time on position;  Stress.Task load is a personal experience,dif-ferent for everybody and dependingon many things.The limitations of thehuman information processing systemare first observed in our ability to com-municate.Overloading this systeminevitably leads to less effective com-munication due to tunnel vision (andtunnel hearing),reduction of scanningcycles,less investment in time to exe-cute feedback and a rising temptationto fall for the trap of expectation bias.This results in more incorrect informa-tion which leads to further incorrectcommunication,and finally decisionsand actions which are error-prone.Weall have a tendency to dismiss the needto invest time in effective communica-tion when it is most needed;underhigh task load.The main issues which have been iden-  January2007   July2007Page 34HINDSIGHTN°5The Briefing Room - Learning from Experience tified during incident investigation andsafety trend analysis are the following:  Pilot reads back incorrectly and thecontroller does not recognise andcorrect the error,often since it isfrom the correct pilot;  Pilot reads back correctly,howeverthis is followed by an incorrectaction on the flight-deck;  Pilot reads back correctly howeverthe controller records the informa-tion incorrectly,resulting in a sub-sequent error.Statistics would also suggest that con-trollers can often pick up errors in com-munication more quickly than pilots.Cardosi,in her 1997 study,recorded thefact that controllers correct 50%ofpilot read-back errors on ground con-trol frequencies and 89%on en-routefrequencies.The reason for this is pos-sibly because not only do controllershave more and varied R/Tcommunica-tion to deal with,but also because theyare constantly tested for their profi-ciency in these skills.Well,having explored some of the trapsthat cause humans to make errors,what are the solutions? These,like thetraps themselves,are not easy to man-age and implement since the commu-nication process itself is highly com-plex.However,here are some tips forboth pilots and controllers which mayhelp:  Use clear and unambiguousphraseology at all times;challengepoor RTF;  Try to avoid issuing more than twoinstructions in one transmission;  Be aware that you tend to be lessvigilant when speaking in yournative language;  Always insist on complete andaccurate read-backs from pilots;  Set the clearance given,not theclearance expected;  Both pilots should monitor the fre-quency whenever possible;  On frequency change,wait and lis-ten before transmitting;  ATC instructions should berecorded where possible;  Use standard phraseology in face-to-face telephone coordination;  Monitor all read-backs,try to avoiddistractions - especially the tele-phone;  When monitoring messages - writeas you listen and read as you speak;  If you are unsure,always check!The European Action Plan for Air-Ground Communication Safety con-tains more information and advice oneffective communication.Copies maybe obtained by completing the formon the EUROCONTROL web-site at
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