Japan Airlines Flight 123

Japan Airlines flight 123 (JAL123, JA123, JL123), a Boeing 747-SR46, , crashed into the ridge of Mount Takamagahara in Gunma Prefecture, Japan 100 km from Tokyo, on Monday August 12, 1985. The crash site was on Osutakano-O'ne (Osutaka Ridge), near Mount Osutaka.

It remains the worst single-aircraft disaster in history, and the second-worst aviation accident of all time, second only to the Tenerife disaster. All 15 crew members and 505 out of 509 passengers died (including the famous singer Kyu Sakamoto) resulting in a total of 520 deaths. There were four female survivors who were seated together in the center of row 56: Yumi Ochiai, an off-duty JAL flight attendant, age 25, who was jammed between a number of seats; Hiroko Yoshizaki, a 34-year-old woman and her 8-year-old daughter Mikiko, who were trapped in an intact section of the fuselage; and a 12-year-old girl, Keiko Kawakami, who was found sitting on a branch up in a tree.

Sequence of events

The flight took off at 6:12 p.m., bound from Tokyo International Airport, Haneda, Tokyo to Osaka International Airport, Itami, Hyogo. About 12 minutes after takeoff, as the aircraft reached cruising altitude over Sagami Bay, its tailplane buckled, shedding 15 feet (5 m) of leading edge and the vertical stabilizer into the sea, depressurizing the cabin, and severing all four of the aircraft's hydraulic lines. A well-known photograph (shown) taken from the ground shows a vertical stabilizer to be missing. The pilots set their transponder to broadcast a distress signal to air traffic control in Tokyo, who allowed the aircraft to descend and gave it heading vectors for an emergency landing. Continued control problems required them to first request vectors back to Haneda, then to Yokota (a U.S. military air base), then back to Haneda again as the aircraft veered all over the map.

After descending to 13,500 feet (4100 m), the pilots reported that the aircraft was "uncontrollable". It flew over the Izu Peninsula, headed for sea, then turned back toward the shore and descended to below 7,000 feet (2100 m) before the pilots managed to return to a climb. The aircraft reached an altitude of 13,000 feet (4000 m) before entering a wild descent into the mountains and disappearing from radar at 6:56 p.m. and 6,800 feet (2100 m). During these oscillations that preceded the crash, the pilots managed a small measure of altitude control by using engine thrust, as the hydraulic lines that powered the aircraft's elevator systems were inoperative. The final moments of the plane occurred when it hit a mountain as a result of this loss of control, flipped, and landed on its back as it skidded to a stop.

Some thirty minutes elapsed from the time the tailplane buckled to the time of the crash, long enough for some passengers to scribble shaky farewells to their families. Some of the passengers, lacking writing instruments, used their own blood to pen their farewell notes.

Rescue operations

The Japanese government claims that because of the rain, unfavorable terrain, and lack of sunlight, rescue crews were unable to reach the crash site until the following morning, twelve hours after the crash. Most of the passengers' remains were identified, and were enshrined at the nearby village of Ueno.

There was some confusion about who would handle the rescue in the immediate aftermath of the crash. A U.S. Air Force helicopter was the first to the crash site, some 20 minutes after impact, and radioed Yokota Air Base to assemble rescue teams and offered to help guide Japanese forces to the site immediately. But Japanese government representatives ordered the U.S. crew to return to Yokota Air Base because the Japan Self-Defense Forces (JSDF) were going to handle the rescue. Although a JSDF helicopter spotted the wreck during the night, it said poor visibility prevented it from landing at the site. JSDF forces did not arrive until the following morning. It is not known whether any survivors of the crash died in this interval. The off-duty flight attendant who survived the crash recounted from her hospital bed that she recalled bright lights and the sound of helicopter rotors shortly after she awoke amid the wreckage, but that nothing further was seen or heard until the JSDF arrived the next day.

It is believed that a substantial number of people survived the initial crash, but succumbed to hypothermia before they could be rescued. The apparent lack of urgency and bungled response to responding to the crash have led to rumors in Japan that the Japanese government was hoping that there wouldn't be any survivors of the crash, reportedly because the airplane was carrying some kind of secret cargo. But, there is very little evidence to support this theory over the more plausible theory that basic, bumbling bureaucracy slowed the Japanese government's and the military's response.

Cause

The cause of the crash according to the official report published by the Japanese Aircraft and Railway Accidents Investigation Commission, is as follows:

The aircraft was involved in a tailstrike incident at Itami Airport on June 2, 1978, which damaged the aircraft's rear bulkhead.
The subsequent repair performed by Boeing was flawed. Boeing's procedures called for a doubler plate with two rows of rivets to cover up the damaged bulkhead, but the engineers fixing the aircraft used two doubler plates with only one row of rivets. This reduced the part's resistance to metal fatigue by 70%. Boeing had calculated that this incorrect installation would only make the plane last 10,000 take-offs, but the plane had accomplished 12,319 take-offs before the accident occurred and after the installation of the new plate was done.
When the bulkhead gave way, it ruptured the lines of all four hydraulic systems. With the aircraft's control surfaces disabled, the aircraft was uncontrollable.

Japan Airlines accepted partial responsibility for the disaster because the tail had been making intermittent whistling noises (suggesting a flaw in the fuselage) for years without action by company maintenance personnel.

The President of Japan Airlines resigned. Several higher- and lower-ranking employees (including the Chief Engineer) of Japan Airlines committed suicide in the aftermath, as did the Boeing engineer who had failed to properly repair the rear bulkhead in 1978.

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In-flight airliner structural failures | Airliner crashes caused by mechanical failure | 1985 | Accidents and incidents in the Japanese aviation sector

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Sequence of events

Rescue operations

Cause

See also

External links