Linguistic Factors in Cockpit Communication

1. Linguistic Factorsin Cockpit Communication Manfred Krifka Humboldt Universität, Berlin collaborating with: Silka MartensFlorian SchwarzCarrie Clarady

2. Research on Cockpit Communication:Some Background • Social dynamics of group interaction as an important factor in the origin of accidents and in the success of dealing with accident-prone situations(cf. Robert Helmreich, “Managing Human Error in Communication”, Scientific American 1997.) • Crew Resource Management (CRM): Rating and improving of crew performance in aviation and other fields in which professional groups interact in situations with high task load. • But over and above the general social dynamics of group interaction, there are specific problems relating to language and communication in such settings.

3. Cockpit Communication • Possible areas of research: • Problems of language (e.g., the structure of human language, features of the technical language). • Problems of communication (that is, problems of language use)

4. Cockpit Communication: Problems of Language • Cf. Stephen Cushing (1994), Communication Clashes and Aircraft Crashes. • Misunderstanding of We are now at takeoffimplied in Tenerife accident in 1977 • Problems of sentence parsing:[back [on the power]] [[back on] [the power]] • Problems of phonological identification:climb to five zero climb two five zero

5. Cockpit Communication: Problems of Communication • Mitigation of contributions especially by the lower-ranked pilot (First Officer or Engineer) for face-serving purposes. • Not very much more fuel. (Engineer to Captain five minutes before engine stopped, United Airlines, Portland, 1978) • (cf. Charlotte Linde, “The quantitative study of communicative success: Politeness and accidents in aviation discourse”, Language in Society 17)

6. Cockpit Communication: Research Techniques • Observation of real situations • Transcripts of communication before and during accidents (recorded by Black Box and published by National Transportation Safety Board) • Observation and ratings of communication of regular flights. • Important data, but difficult to come up with generalization from particular cases. • Observation of communication in flight simulators • Experimental scenarios. • Similar scenarios for different crews. • Advanced simulator techniques guarantee closeness to reality. • But: Simulator sessions extremely costly.

7. Group Interaction in High Risk Environments:Linguistic Factors GIHRE Subproject, sponsored by Gottlieb Daimler and Karl Benz Foundation. First project phase at Department of Linguistics, University of Texas at Austin, with Carrie Clarady.

8. Linguistic Factors: First Project Phase • Basic Questions: • Correlation: Task Load  Communicative Behavior • Correlation: Crew Performance  Communicative Behavior

9. Linguistic Factors: First Project Phase • Data: • Simulation flights on B727 with similar scenario, carried out by NASA, 1987 • Transcribed by University of Texas Aerospace Crew Research Project(thanks to Bob Helmreich and Brian Sexton) • Every flight has 4 transcribed segments:A: climbout from SF, descent and landing into SAC: Medium task load. • B: Descent, approach and landing at LAX, with runaway trim, jammed stabilizer, low oil pressure: High task load.C: Descent to SAC, missed approach: Medium task load.D: Diversion to SJC, with hydraulic malfunction, diversion to SFC, split flap malfunctio: High task load. • Performance of crews and crew members was rated • We investigated 5 (+ 1/2) flights (2 well-performing crews, 3 poorly performing crews) (alltogether 9 hours, 6900 thought units)

10. Communication Density:Thought Units per minute, Crew 4 Segment A Segment BSegment C Segment D No difference in speech time well-performing / poorly performing crews

11. Factors Presentation of Data: Segments: A Medium (task load)BCD High (task load) Crews: 3 Poor (crews)45 8 13 Good (crews) Data are given in proportion to “thought units” (chosen by transcribers)

12. Speaker and Addressee Roleper Thought Unit • Captain assumes speaker role most often. • Engineer assumes speaker role more often in high task-load segments.

13. Speaker and Addressee Roleper Thought Unit • Engineer is adressed more often in high task-load segments.

14. Reference to Participants • Slightly more reference to group in good crews, high task loadscf. Sexton, J.B. & Helmreich, R.L. (2000). Analyzing cockpit communication. The links between language, performance, error, and workload. Human Performance in Extreme Environments 5, 63-68.

15. Speech Act Classification • Question: Correlation Task Load / Group Performance <=> Speech Acts? • Classical Speech Act Classification: Austin, Searle. • Representatives • commit the speaker to truth of proposition, e.g. asserting, concluding; • degree of commitment can vary, e.g. saying, hypothesizing; • may relate to other parts of discourse, e.g. replying • Directives • speaker tries to get the addressee to do something, e.g. requesting, questioning; • degrees can vary, e.g. suggesting, commanding • Commissives • commit the speaker to an action, e.g. promising, threatening, offering • degrees can vary, e.g. promising, guaranteeing • Expressives • express a psychological state, e.g. thanking, apologizing, welcoming • Declarations • changes the institutional state of affairs, e.g. baptizing, marrying, declare a person guilty

16. Problems of Speech Act Classification • Existing classifications are difficult to apply • Difference between form and meaning • Direct command: Close the door.(Command : Imperative) • Indirect command: The door should be closed.(Command : Declarative) • Indirect command: Why don’t you close the door?(Command : Question) • Very indirect command: It’s cold in here. (not a command, but a statement (*please), but may have similar action implications as commands)

17. Problems of Speech Act Classification 2 • Individuating speech acts • ABC 801, that turn looks like it’s going to take you through, so continue the right turn to 180.(Command, or Assertion + Command, or Attention-Call + Assertion + Command?) • [8.1530] I’m on the air, so you get it.(Command, or Assertion + Command, or Motivated Command?) • Neglect of communication-regulating acts • Call for attention, acknowledgements, repetitions etc.do not figure prominently in speech act classifications • Some investigation of such features in Conversation Analysis (Reference)

18. Problems of Speech Act Classification 3 • Multi-dimensional nature of speech acts • A question can be related to a statement,a command, a prior statement, etc.:What’s the weather like in Sacramento?What should I do now?What did you say? • A command can be related to an action, a statement, a question, a prior statement, etc.:Now you fly the airplane.Tell me what’s the weather like in Sacramento.Ask him what the weather is like in Sacramento.Tell me again, please.

19. Our Speech Act Classification • A “pragmatic” approach: What is potentially predictive for crew performance? • Does not follow formal, but functional criteria, if the intended function is clear.Why don’t we go to the book and see what you can do on it?is classified as a command, not a question. • Classifies each previously identified thought unit as belonging to one speech act category.

20. Our Speech Act Classification (2) • Combines speech act types (e.g., assertion of a proposition) with content features (e.g., report of action, report of previous report, prognosis, diagnosis) • Factors out classification of question / answer:You got any problems classified as statement / questionYou want me to brief with you? as command / question • Assumes a category of “regulatives” that are concerned with the proper flow of information

21. Speech Act Categories Searle’sClassificaiton Represen-tatives Directives Commissives Expressives “Regulatives”

22. Examples of Speech Act Types • Status Reports • [4.17] UH ROGER UH WE ARE OUT AT 1443 AND OFF AT 53 FROM SAN FRANCISCO • [4.62] UH, ABC 801, BE ADVICED THE METER LOCATOR OUTER MARKER IS UNRELIABLE, I’LL CALL YOU AT METER • [8.28] WE HAVE AN UNDEREXCITED FAULT LIGHT ON, UH, NUMBER 3 • [8.89] OKAY, WE’RE COMING TO 350 DESCENDING TO 5, ABC 801 • Reports of Action • [4.75] I KEEP LOOKING FOR THE ALTITUDE RIGHT HERE AND SEE 801 • [4.111] I’LL PUT IT ON THE MISSED APPROACH ALTITUDE • Reports of Report • [4.461] WELL, HE TOLD US BE READY FOR ILS 24 RIGHT • (Not used for reciting from manuals, or relaying information in general) • Prognoses • [4.373] OKAY, SO I THINK IF WE DO THE TWO ENGINE, THE TWO GENERATOR OPERATION THAT’LL BE UH, THE NEXT THING. • Diagnoses • [8.111] I THINK WHAT THAT LIGHT WAS, WAS WHEN THAT FIELD, FILED RELAY TRIPPED.

23. Examples of Speech Act Types 2 • Commands • [8.94] HEY, WITH THIS FAULT LIGHT, WOULD YOU SWITCH ESSENTIAL POWER OFF OF NUMBER 3, PLEASE FOR ME • [8.212] ABC 801, THAT TURN LOOKS LIKE IT’S GOING TO TAKE YOU THROUGH, SO CONTINUE THE RIGHT TURN TO 180 • [8.356] PRESS ON • [8.64] OKAY, NOW YOU FLY THE AIRPLANE • [8.224] WHY DON'T YOU MAKE IT 190. • [8.305] FINAL FLAPS SHOULD BE 30 • Permissions • [8.19] UNITED 801’S CLEARED FOR TRAFFIC. YOU CAN DESCENT AT PILOT’S DISCRETION. • [8.15] OH, WHATEVER YOU WANT TO DO HERE, BOB • Complies • [8.414] [HOW ABOUT THAT BRAKE? NOW TRY IT.] NO. • Report of Intention • [8.32] MEANWHILE I’LL TAKE CARE OF THE APPROACH/DESCENT HERE • [8.63] WE’LL…WE’LL TAKE CARE OF THAT

24. Examples of Speech Act Types 3 • Expressives • [4.185] UH, SHIT • [8.639] LITTLE DEVIL • [8.904] BOY THAT IS A LOT OF PRESSURE • [8.989] GREAT, EXCELLENT, NO, EXCELLENT • [8.1019] COME ON, BABY, COME AROUND HERE • Acknowledgements • [4.13] [ABC 801, EXPECT ILS 16 APPROACH TO SACRAMENTO] OKAY. • [8.410] [I’L JUST CRANK IT AND YOU TELL ME WHEN TO STOP]. YEAH. • Affirmations • [8.1075] [WELL WE GOT… WE’RE COMMITTED TO THE RIGHT] THAT’S RIGHT • [8.1120] [CANT’T DO IT] NO [AGREEMENT]. • [8.1169] [SHOULDN’T BE THAT MUCH OF A PROBLEM]. NOPE, NO NO NO. • Rephrases • [8.50] [ONE SIX RIGHT, APPROACH.] ONE SIX RIGHT, YEAH. • [8.1640] [GROUND SPOILERS, OUT SPOILERS] OUT SPOILERS.

25. Speech Act Classification More prognoses / diagnoses in well-performing crews.

26. Speech Act Classification More reports of intention in well-performing crews.

27. Speech Act Classification • Slightly more questions in well-performing crews. • More questions are answered in well-performing crews(0.54 in poorly performing crews, 0.77 in well performing crews)

28. Speech Act Classification • Fewer commands in well-performing crews. • Fewer explicit complies in well-performing crews.

29. Speech Act Classification • Fewer expressives and emotional words in well-performing crews. • Fewer expressives and emotinal words in situations of high task load for poorly performing crews.

30. Limitations of Study • Correlation Segements / Task Load only very coarse. • Number of crews analyzed far too low for any significance measure. • Quality of transcripts rather varied, e.g. no information about paralinguistic features. • Information about flight scenario and precise timing of malfunctions was rather limited. • Revisions of speech act categories necessary. • No classification of higher-order features of communication.

31. Examples of features that were not encoded Multiple rephrases (Crew 8) [8.146] E-C: CLIMB TO 500 FEET, PROCEED DIRECT SACRAMENTO VOR. HOLD SOUTH 180 RADIAL, 5,000 FEET. C-E: 5,000? E-C: YEAH. C-E: AFTER 500, DIRECT TO VOR TO HOLD? E-C: RIGHT. C-E: OKAY, GOT IT Invoking Crew Resources[8.1511]YOU CAN, YOU CAN LISTEN WITH ME, I MIGHT MISUNDERSTAND. [8.2167] WHAT ELSE? WHAT HAVE WE MISSED? Prioritizing goals (Crew 8) [8.368] WE WON'T WORRY ABOUT ANY OF THAT STUFF. [8.2007] F-C: I'M WORRIED ABOUT THE GAS. WE'RE PISSIN' OUT 15,000 POUNDS AN HOUR. C-F: DON'T WORRY. C-F: DON'T WORRY. F-C: OK. C-F: I'LL TELL YA WHEN TO WORRY.

32. New Project Phase(June 2001 - ) Data:Flight simulator data, but with a much more constrained scenarioin which communication skills are crucial

33. Flight Simulator Scenario • Developed by Gerd Fahnenbruck, carried out by Lufthansa CityLine on Canadair Regional Jet • Circling approach due to glide slope failure, runway has to be approached from unusual direction, a plane is blocking the runway, fly a go around • Normal second approach, break down of glide slope requiring constant communication about altitude • Take-off followed by double instrument failure requiring constant communication about conflicting values

34. Data, Transcripts, Analysis • Video data (4 cameras) and audio data available • 16 flights, average length 53 minutes • Identification of three segments with different types of task load across crews. • Careful transcriptions, including features of prosody, intonation, pauses • Refined system of speech act classification, following “Qualitative Development Analysis”(T. Diegritz & C. Fürst, Empirische Sprechhandlungsforschung. Erlangen 1999):

35. Example: Steps of analysis (QVA)

36. Example: Steps of analysis (QVA) so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20.

37. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description

38. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description After initiating the utterance with the particle soCaptain utters a question with rising intonation. Directly after this, as the captain is looking at the instrument panel, he utters a statement with strongly rising intonation.

39. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description • Division in speech acts

40. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description • Division in speech acts • There are three subsequent illocutionary acts: • so • wie weit sin mer • flaps man wir twenty

41. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description • Division in speech acts • Context

42. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description • Division in speech acts • Context Reading back: Due to the instrument failure, first officer informs captain that he can only fly in stand-by mode. Captain agrees that it would be best not to split up the tasksbut to let first officer fly alone in stand-by mode. Captain remarks that he can still help a little bit.

43. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description • Division in speech acts • Context • Explicit interpretative verbalization

44. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description • Division in speech acts • Context • Explicit interpretative verbalization We have made it clear how we will proceed. Let us check the current state, to see how far we are in respect to the planned approachwith the instrument failure. I will go ahead and check the flaps, which are 20.

45. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description • Division in speech acts • Context • Explicit interpretative verbalization • Perlocutionary effects

46. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description • Division in speech acts • Context • Explicit interpretative verbalization • Perlocutionary effects First officer reacts with a confirming ja.

47. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description • Division in speech acts • Context • Explicit interpretative verbalization • Perlocutionary effects • Aspects of development

48. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description • Division in speech acts • Context • Explicit interpretative verbalization • Perlocutionary effects • Aspects of development • Thematic progression Captain marks a thematic break by ending the previous sequence of clarification and going on to deal with the problem himself. • Relational development Captain integrates first officer actively and cooperatively in the problem solving process, by asking himself and the first officer and by answering his own question.

49. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description • Division in speech acts • Context • Explicit interpretative verbalization • Perlocutionary effects • Aspects of development • Assigning speech act type

50. Example: Steps of analysis so. wie weit sin mer? flaps ham wir twenty.So. How far are we? As for the flaps we have 20. • Description • Division in speech acts • Context • Explicit interpretative verbalization • Perlocutionary effects • Aspects of development • Assigning speech act type So. STRUCTURING SIGNAL I indicate that I am about to start a speech act and that the previous discussion is over.