San Francisco

Immediately after liftoff the stick shaker activated, and the first officer, who was making the takeoff, said 'you got it.' The captain took control, closed the thrust levers, and landed. He applied full reverse thrust and maximum braking, and turned the airplane off the runway to avoid a barrier at the end. A system design deficiency permitted a malfunctioning aoa sensor to cause a false stall warning. The sensor had experienced 9 previous malfunctions, and was inspected and returned to service without a determination on the reason for the intermittent malfunction. The first officer had incorrectly perceived that the airplane was stalling and gave control to the captain without proper coordination of the transfer of control. All 292 occupants were rescued, among them 10 were injured, one seriously.

A recently discharged USAir employee boarded PSA flight 1771 after having left a goodbye message with friends. He bypassed security and carried aboard a borrowed 44 caliber pistol. A note written by this passenger, found in the wreckage, threatened his former supervisor at USAir, who was aboard the flight. At 1613, the pilot reported to Oakland ARTCC that he had an emergency and that gunshots had been fired in the airplane. Within 25 seconds, Oakland control controllers observed that PSA 1771 had begun a rapid descent from which it did not recover. Witnesses on the ground said the airplane was intact and there was no evidence of fire before the airplane struck the ground in a steep nose-down attitude. The cover tape revealed the sounds of a scuffle and several shots which were apparently fired in or near the cockpit. The pistol was found in the wreckage with 6 expended rounds. FAA rules permitted airline employees to bypass security checkpoints. All 43 occupants were killed.

The aircraft, a Gates Learjet 24B, modified by a Howard/Raisebach Mark II conversion, was cleared for takeoff on runway 28L. Tower personnel estimated that the aircraft rotated for takeoff at 3,200 feet down the runway and was at approximately 200 feet agl when the pilot was instructed to contact departure control. Witnesses observed the aircraft climbing in a wings level attitude when it entered the broken cloud layer at about 600 feet agl. Moments later, the aircraft was observed descending out of the clouds at a steep angle and in a left wing low/nose down attitude. The aircraft impacted between runway 28L and 28R, approximately 10,000 feet from the approach ends. Witnesses reported that the engines sounded like they were operating at a high power setting. An exam of the engines revealed evidence that both were at or above 92% power at impact. No preimpact part failure/malfunction was found. Records revealed two autopilot discrepancies on 10/4/84; one induced the roll mode was sensitive; the other induced the autopilot intermittently rolled the aircraft into a standard rate left bank when engaged. Reportedly, the autopilot would not have been used for takeoff. All three occupants were killed.