Date & Time:
Mar 17, 1982 at 0810 LT
Type of aircraft:
Airbus A300
Operator:
Registration:
F-BVGK
Flight Phase:
Takeoff (climb)
Flight Type:
Scheduled Revenue Flight
Survivors:
Yes
Schedule:
Sanaa - Cairo - Paris
MSN:
070
YOM:
1979
Flight number:
AF125
Country:
Yemen
Region:
Asia
Crew on board:
13
Crew fatalities:
0
Pax on board:
111
Pax fatalities:
0
Other fatalities:
0
Total fatalities:
0
Aircraft flight hours:
9053
Aircraft flight cycles:
3376
Circumstances:
During the takeoff roll at Sana'a Intl Airport, at a speed of 95 knots, the crew noticed a loud bang followed by vibrations. The captain decided to abandon the takeoff procedure and initiated an emergency braking maneuver. The airplane came to rest on runway with its right wing on fire. All 124 occupants were evacuated safely, nevertheless, two passengers were slightly injured. The aircraft was considered as damaged beyond repair.
Probable cause:
The accident directly resulted from the uncontained explosion of a first stage high pressure turbine disk of the right hand engine. The propagation of a low cycle fatigue crack on one of the embossments of the disk rim was at the origin of the disk fracture. This cracks, which existed before, had not been detected during the inspection conducted in the operator's workshops, according to the method defined by the manufacturer and in accordance with the requirements of the airworthiness authority. The investigations showed that it was necessary, not only to reduce the intervals between the inspections of these disks and conduct two independent sequential inspections, but also to modify the design and make sure they were progressively replaced by the new type. It seems obvious that the limit life validation methods used at the time of the accident, were still insufficient, as far as the probability of non-detection of cracks was concerned.
