Alaska Airlines Flight 261

Alaska Airlines Flight 261 was a scheduled international passenger flight from Licenciado Gustavo Díaz Ordaz International Airport in Puerto Vallarta, Jalisco, Mexico, to Seattle–Tacoma International Airport in Seattle, Washington, United States, with an intermediate stop at San Francisco International Airport in San Francisco, California. On January 31, 2000, the aircraft operating the route, a McDonnell Douglas MD-83, crashed into the Pacific Ocean roughly 2.7 miles (4.3 km; 2.3 nmi) north of Anacapa Island, California, following a catastrophic loss of pitch control. The accident killed all 88 on board: two pilots, three cabin crew members, and 83 passengers.

The subsequent investigation by the National Transportation Safety Board (NTSB) determined that inadequate maintenance led to excessive wear and eventual failure of a critical flight control system during flight. The probable cause was stated to be "a loss of airplane pitch control resulting from the in-flight failure of the horizontal stabilizer trim system jackscrew assembly's trapezoidal nut threads. The thread failure was caused by excessive wear resulting from Alaska Airlines' insufficient lubrication of the jackscrew assembly."

Aircraft
The aircraft involved in the accident was a McDonnell-Douglas MD-83, serial number 53077, and registered as N963AS. The aircraft was the 1995th DC-9/MD80 family airframe built, was manufactured and delivered new to Alaska Airlines in 1992 and had logged 26,584 flight hours and 14,315 cycles before the crash.

Crew
The pilots of Flight 261 were both highly experienced aviators. Captain Edward "Ted" Thompson, 53, had accrued 17,750 flight hours, and had more than 4,000 hours experience flying MD-80s. First Officer William "Bill" Tansky, 57, had accumulated 8,140 total flight hours, including about 8,060 hours as first officer in the MD-80. Neither pilot had been involved in an accident or incident prior to the crash. There were three Seattle-based flight attendants on board.

Passengers
The three flight attendants and 47 of the passengers on board the plane were bound for Seattle. 32 passengers were traveling to San Francisco; three were bound for Eugene, Oregon; and three passengers were headed for Fairbanks, Alaska. Of the passengers, one was Mexican and one was British, with all others being American citizens.

At least 35 occupants of Flight 261 were connected in some manner with Alaska Airlines or its sister carrier Horizon Air, including twelve actual employees, leading many of the airlines' personnel to mourn for those lost in the crash. Alaska Airlines stated that it was commonplace, on less busy flights, for employees to fill seats that would otherwise have been left empty. Bouquets of flowers started arriving at the company's headquarters in SeaTac, Washington, the day after the crash.

Notable passengers

 * Jean Gandesbery, author of the book Seven Mile Lake: Scenes from a Minnesota Life, died alongside her husband, Robert.
 * Cynthia Oti, an investment broker and financial talk show host at San Francisco's KSFO-AM.
 * Tom Stockley, wine columnist for The Seattle Times.
 * Morris Thompson, commissioner of the Bureau of Indian Affairs from 1973 to 1976, died alongside his wife Thelma and daughter Sheryl.

Initial flight segment
Alaska Airlines Flight 261 departed from Puerto Vallarta's Licenciado Gustavo Díaz Ordaz International Airport at 13:37 PST (21:37 UTC), and climbed to its intended cruising altitude of flight level 310 (31,000 feet or 9,400 meters). The plane was scheduled to land at San Francisco International Airport (SFO). Some time before 15:49 (23:49 UTC), the flight crew contacted the airline's dispatch and maintenance control facilities in SeaTac, Washington, on a company radio frequency shared with operations and maintenance facilities at Los Angeles International Airport (LAX), to discuss a jammed horizontal stabilizer and a possible diversion to LAX. The jammed stabilizer prevented operation of the trim system, which would normally make slight adjustments to the flight control surfaces to keep the plane stable in flight. At their cruising altitude and speed, the position of the jammed stabilizer required the pilots to pull on their yokes with approximately 10 pounds (44 N) of force to keep level. Neither the flight crew, nor company maintenance, could determine the cause of the jam. Repeated attempts to overcome the jam with the primary and alternate trim systems were unsuccessful.

During this time, the flight crew had several discussions with the company dispatcher about whether to divert to LAX, or continue on as planned to SFO. Ultimately the pilots chose to divert. Later, the National Transportation Safety Board (NTSB) found that while "the flight crew's decision to divert the flight to Los Angeles [...] was prudent and appropriate", "Alaska Airlines dispatch personnel appear to have attempted to influence the flight crew to continue to San Francisco [...] instead of diverting to Los Angeles". Cockpit voice recorder (CVR) transcripts indicate that the dispatcher was concerned about the effect on the schedule ("flow"), should the flight divert.

First dive and recovery
At 16:09 (00:09 UTC), the flight crew successfully unjammed the horizontal stabilizer with the primary trim system. However, upon being freed, it quickly moved to an extreme "nose-down" position, forcing the aircraft into an almost vertical nosedive. The plane dropped from about 31,500 ft (9,600 m) to between 23,000 and 24,000 ft (7,000 and 7,300 m) in around 80 seconds. Both pilots struggled together to regain control of the aircraft, and only by pulling with 130 to 140 pounds (580 to 620 Newtons) on the controls did the flight crew stop the 6,000 ft/min (1,800 m/min) descent of the aircraft and stabilize the MD-83 at approximately 24,400 ft (7,400 m).

Alaska 261 informed air traffic control (ATC) of their control problems. After the flight crew stated their intention to land at LAX, ATC asked whether they wanted to proceed to a lower altitude in preparation for approach. The captain replied: "I need to get down to about ten, change my configuration, make sure I can control the jet and I'd like to do that out here over the bay if I may." Later, during the public hearings into the accident, the request by the pilot not to overfly populated areas was mentioned. During this time, the flight crew considered, and rejected, any further attempts to correct the runaway trim. They descended to a lower altitude and started to configure the aircraft for landing at LAX.

Second dive and crash
Beginning at 16:19 (00:19 UTC), the CVR recorded the sounds of at least four distinct "thumps", followed 17 seconds later by an "extremely loud noise", as the overstrained jackscrew assembly failed completely and the jackscrew separated from the acme nut holding it in place. As a result, the vertical stabilizer failed, and the aircraft rapidly pitched over into a dive. The crippled plane had been given a block altitude, and several aircraft in the vicinity had been alerted by ATC to maintain visual contact with the stricken jet. These aircraft immediately contacted the controller. One pilot radioed, "That plane has just started to do a big huge plunge." Another reported, "Yes sir, ah, I concur. He is, uh, definitely in a nose down, uh, position, descending quite rapidly." ATC then tried to contact the plane. The crew of a SkyWest airliner reported, "He's, uh, definitely out of control." Although the CVR captured the co-pilot saying, "mayday", no radio communications were received from the flight crew during the final event.

The CVR transcript reveals the pilots' continuous attempts for the duration of the dive to regain control of the aircraft. At one point, unable to raise the nose, they attempted to fly the plane upside-down in an effort to maintain control. It was, however, far beyond recovery, and descended, inverted and nose-down, about 18,000 feet (5,500 m) in 81 seconds (151 mph; 243 km/h). A few seconds before 16:22 (00:22 UTC), Flight 261 impacted the Pacific Ocean at high speed, about 14 miles (23 kilometers; 12 nautical miles) offshore, between the coastal city of Port Hueneme, California, and Anacapa Island. At this time, pilots from aircraft flying in the vicinity reported in, with one SkyWest Airlines pilot saying, "...and he's just hit the water." Another reported, "Ah, yes sir, he, ah, he, ah, hit the water. He's, ah, down." The aircraft was destroyed by the impact forces, and all occupants on board were killed by blunt force impact trauma.