“"A jackscrew stripped bare. A crew fought for eighty minutes. Eighty-eight people fell into the Pacific because maintenance intervals were stretched too far."”
Alaska Airlines Flight 261, flying from Puerto Vallarta to San Francisco and onward to Seattle, abruptly pitched over and dove into the Pacific Ocean. The horizontal stabilizer jackscrew assembly's acme nut threads had stripped completely due to excessive wear. The threads were the only load path for pitch trim; when they failed, the stabilizer moved uncontrollably. The crew fought the aircraft for over 80 minutes, inverting it at one point in an attempt to stabilize the descent, but the condition was unrecoverable. All 88 occupants perished. The NTSB found that Alaska Airlines had extended its lubrication and end-play inspection intervals beyond safe margins, and a plugged grease fitting had left the jackscrew essentially unlubricated.
Study Hook: Alaska Airlines 261's crew inverted the aircraft trying to regain pitch control after the jackscrew stripped. How did extended maintenance intervals, a plugged grease fitting, and the absence of a fail-safe mechanism in the MD-83 design create a single point of failure that killed 88 people?
Visual Prompt: A dark Pacific Ocean at dusk, with a search vessel's spotlight illuminating floating debris and a section of MD-83 tail section, Coast Guard cutters circling the area, and the California coastline barely visible on the horizon.
Tags: [Alaska Airlines 261, MD-83, jackscrew, horizontal stabilizer, maintenance error, NTSB, Pacific Ocean, 2000]
Alaska Airlines 261's crew inverted the aircraft trying to regain pitch control after the jackscrew stripped. How did extended maintenance intervals, a plugged grease fitting, and the absence of a fail-safe mechanism in the MD-83 design create a single point of failure that killed 88 people?