An expert crew experiences simultaneous system anomalies after touching down on a short runway.
Immediately after touchdown, the pilot monitoring made calls indicating that the speed brakes and thrust reversers had deployed when, in fact, they had not. The Safety Board evaluated possible explanations for the captain's “erroneous and premature speed-brake and thrust-reverser callouts and his failure to monitor and notice that the speed brakes had not automatically deployed as expected.”
According to the Board, the only positive indication available to the captain to verify extension of the speed brakes would have been the aft position of the handle, which was visible from and within reach of both pilots' seating positions. FDR data showed that the speed-brake handle was in the armed position for landing and began to move within 1 sec. of landing but did not continue to move to the aft (extended) position as expected. The Safety Board concluded that the captain's speed brakes “deployed” callout was likely made in anticipation (not in confirmation) of speed-brake deployment after he observed the speed-brake handle's initial movement. Both pilots likely presumed that the reliable automatic speed-brakes were functioning normally and focused on the thrust-reverser problem after the “deployed” callout was made.
About the same time that the speed-brake handle started to move, the amber annunciation lights on the EICAS display would have provided the captain with a cue that the thrust reversers were in transition. Although the captain called out “two in reverse,” this callout was not based on the illumination of the green annunciation since the air/ground sensing system cycling to “air” mode prevented the reversers from deploying at that time. (Immediately following the captain's “two in reverse” callout, the CVR recorded the first officer stating, “No reverse” in a voice that sounded strained.) Given the typical reliability of the thrust-reverser system, it is likely that the captain made the callout because he expected normal thrust-reverser activation.