Flight Crew Callouts and Aircraft Automation Modes An Observational Study of Task Shedding

Abstract

New aircraft come with a set of recommended standard operating procedures, in the case of multi-crew aircraft this includes "callouts"-verbalizations of particular flight guidance automation mode changes. In an attempt to reduce the risk for mode confusion some operators have required flight crews to callout all flight guidance automation mode changes as a means of forcing pilots to monitor the Flight Mode Annunciator (FMA). Previous research has shown that crews do not spend enough time on the flight mode annunciator, and skip mode call-outs as well as making call-outs in advance of annunciations; there has been no report of any system or regularity in the shedding and adaptation of callouts. One reason could be the contrived empirical simulator settings of such research, which we aimed to augment with natural observations of real cockpit work reported here. With the hope of answering, in more detail, how required verbal coordination of annunciated mode changes gets adapted to real settings we observed 19 line flights with three different airlines from the first observer's seat in the cockpit. We found that many callouts were simply shed in high-workload situations, and found regularity in the kind of callouts being shed. Callouts relating to aircraft automation, such as FMA call-outs, were shed before other required callouts. Our results suggested that FMA callouts were not used as a tool to detect or remember automation mode changes but as a vehicle for coordinating between the pilots themselves, a finding that could serve as a reminder for future design of callout procedures.