Report: Japan Airlines Flight 123
By: Chris Kilroy
The Boeing 747SR (Short Range) is an aircraft that
was designed to be used on short, high-density routes. Due to its lower fuel
capacity, it is capable of carrying over 550 passengers. For Japan Airlines
747SR, JA8119, Monday August 12, 1985 began no different than any other day.
The aircraft had previously flown in from Kyushu and had arrived back at
Haneda, Tokyo at 5:17 p.m. The aircraft was refuelled and new flight crew
boarded, while the cabin crew remained from the previous flight. The
only anamoly on this flight was that the First Officer was being upgraded
by a Check Captain for promotion himself to Captain. JAL123, which was the
assigned flight number for this trip, taxiied away from the gate at 6:04pm
with 509 passengers on board, ready for the flight to the industrial city
of Osaka which was 400km away.
|An amateur photographer shot this photo of Japan Air 123 from the ground. Note the missing vertical stabilizer.
In command of this flight was Captain Masami Takahama,
49, who was a Training Captain and had been with the company for nineteen
years. He had 12,500 hours of total flight time. The flight took off
at 6:12pm, and five minutes later while climbing on track to FL240 in visual
conditions asked Tokyo ATC for a more direct route to Osaka. Tokyo Approved
this request. Six minutes later as Tokyo ATC was tracking the flight, the
emergency transponder code appeared on their screen, which was 7700. This
is the emergency sqawk for aircraft in distress.
Aircraft: " Tokyo,
Japan Air 123 . Request immediate... ah... trouble. Request return back to
Haneda... descend and maintain flight level two two zero."
Controller: "Roger approved as you requested!"
Aircraft: "Radar vector to Oshima please"
Controller: "Turn right, heading 090, radar vector
The controller noticed
that instead of making the 177° turn back toward Oshima Island,
the aircraft was making only a gradual turn to the right onto a course
of 50°. Crossing the Izu Peninsula and leaving it astern, it then headed
out over Suruga Bay in a north-westerly direction. The aircraft had suffered
an explosive decompression of its rear vertical tail plane, losing
a 15 foot section of the leading edge and having all its flying controls
|The actual route of Japan Air 123 during the accident. Click for larger view.
The aircraft impacted the
lower slopes of Mount Osutaka, killing all but four people on board.
The cause was found to be an improperly repaired rear pressure bulkhead,
which had been repaired by Boeing some years before after the aircraft had
been involved in a tail scrape on landing. This caused the loss of the flying
surfaces in the tail, and the control surfaces to a certain extent on the
wings. This was and still is the worlds worst accident involving a