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Source: lessonslearned.faa.gov
pickle switches?” Suitcase handle was a colloquialism for a mechanism on the pedestal that commanded the electric trim motor. Pickle switches performed the same function on the yoke. The mechanic was wondering if a switch had failed.
The captain told the mechanic: “[Pitch trim] appears to be jammed...the whole thing.” This innocuous exchange would result in a befuddling sequence of events. Without communicating with the first officer (who was the pilot fly- ing), the captain apparently decided to try the trim one last time. The only record of this moment – which occurred four seconds following his conversation with the LAX mechanic – was the captain muttering (apparently to himself): “Let’s do that.” This was followed by the sound of a click, then a clunk, then two faint thumps, and then an expletive as the aircraft pitched aggressively down. The first officer would ask in alarm, “What are you doing?”
In the following two minutes, the aircraft descended from 31,000 feet to 23,000 feet. Twenty-five seconds after the dive began, the captain informed ATC, “We’ve lost vertical control of our airplane.” There was limited communication with ATC for the next minute. It is likely that the controller identified Flight 261 as an emergency aircraft at this point. Only once in the transcript does the crew explicitly declare an emergency – and it was the first officer, one minute prior to the crash, who exclaimed, “Mayday” (he never actually transmitted the phrase over the radio – it was captured on internal microphones).
The aircraft would recover for several minutes at 24,000 feet. The threads in the jackscrew nut had completely failed, resulting in the horizontal stabilizer moving to its nose-down mechanical stop (the nut threads would later be found tangled around the jackscrew). The crew managed to maintain basic control for the next nine minutes. During this period, the captain once again communicated with a mechanic on the ground at LAX, explaining that the trim had ran away full nose down. The mechanic inquired as to whether the crew had attempted to trim the nose back to a neutral state. The captain responded: “I’m afraid to try it again...”
8 • TWIN & TURBINE / December 2020
Thirty seconds later, the captain asked the first officer, “You wanna try [the trim] or not?” The first officer responded: “Boy, I don’t know.” The captain would demure: “It’s up to you, man.” The first officer suggested proceeding to LAX. He also suggested briefing the passengers. The captain would do so and then descend once again, this time intentionally.
The captain decided to test the flaps at 17,000 feet. He noted that the configuration helped stabilize the aircraft. Then – for unknown reasons – he directed that the flaps be retracted again. The aircraft accelerated from 248 knots to 270 knots following retraction and once again became dif- ficult to control. A minute later, the CVR recorded a sound similar to the movement of the slat/flap handle. Four sec- onds later, the aircraft would enter its final, fatal dive. The horizontal stabilizer, abnormally stressed due to elevator loads (exacerbated by the second selection of flaps at rela- tively high speed), finally failed completely – the structure connecting it to the vertical spar crumpled, resulting in an uncontrollable condition.
The captain’s flying skills would prove unusually sharp at this point. Recognizing the danger of the nose down pitch, he would apparently decide to roll the aircraft inverted. He would exclaim: “Push and roll, push and roll. Ok, we are inverted...at least upside down, we’re flying.”
The aircraft was doomed at this point. The elevator did not have the control authority needed to compensate for the failed horizontal stabilizer. Compressor stalls were soon heard on the CVR due to the negative angle of attack on the inverted engines. Just before impact, the captain uttered his final words: “Ah, here we go.” Unquestionably this comment was made by an individual who knew that he was about to die. The captain never gave up, fighting to the very end. His final moments proved to be ones of courage.