Toa Domestic Airlines Flight 63
| Toa Domestic Airlines Flight 63 | |
|---|---|
 an identical YS-11 from Toa Domestic Airlines |
|
| Accident summary | |
| Accident type | Controlled flight into terrain |
| place | 15 km NNW of Hakodate Airport |
| date | 3rd July 1971 |
| Fatalities | 68 |
| Survivors | 0 |
| Aircraft | |
| Aircraft type | NAMC YS-11A-227 |
| operator | Toa Domestic Airlines |
| Mark | JA8764 |
| Departure airport | Sapporo Chitose Airport |
| Destination airport | Hakodate Airport |
| Passengers | 64 |
| crew | 4th |
| Lists of aviation accidents | |
On July 3, 1971, a NAMC YS-11A on Toa Domestic Airlines Flight 63 collided with Mount Yokotsu-dake about 15 kilometers north-northwest of the destination airport while approaching Hakodate . All 68 occupants were killed in the accident. It is the worst incident for this type of aircraft.
Flight history
The Toa Domestic Airlines NAMC YS-11 ( registration number : JA8764) took off from Sapporo for a scheduled flight to Hakodate at around 5:30 p.m. local time . As the machine approached the destination airport in very poor weather conditions at an altitude of 6000 feet (1830 meters), the pilots announced that they were over the non-directional radio beacon (NDB) Hakodate. At the same time, the crew initiated a 360-degree turn in a northeastern direction and began the descent to 2500 feet (760 meters). Shortly afterwards, around 6:05 p.m., the YS-11 crashed on Mount Yokotsu-dake. Rescue workers only reached the scene of the accident the following day. They did not find any survivors.
Cause of accident
The approach to the destination airport should take place via the NDB Hakodate, the only navigation aid on site. The pilots flew over the radio beacon two minutes before the estimated time of arrival, but did not notice this due to an incorrect display on the radio compass (ADF) and thus misjudged their position. They also missed the fact that the machine had been shifted increasingly northwards by a strong southwest wind. The accident investigators considered it likely that the malfunction of the radio compass was caused by the weather.
Because of the faulty ADF display, the pilots did not initiate the 360-degree turn and the descent via the radio beacon, but about nine kilometers (5 NM ) further north and ended up over mountainous terrain. The investigation committee recommended the installation of a rotary radio beacon with a range finder (VOR / DME) and an instrument landing system at Hakodate Airport in order to avoid similar accidents.
Individual evidence
- ↑ a b c aviation catastrophes, David Gero, Stuttgart 1994
- ^ Aviation Safety Network, Accident Report: JA8764, July 3, 1971