Sunday, 5th of January, 1969
– United Kingdom
Ariana Afghan Airlines Flight 701, an international scheduled passenger flight from Kabul to London-Gatwick, with Intermediate stops were made at Kandahar, Beirut, Istanbul and Frankfurt., operated with a Boeing 727-113C, registration YA-FAR, crashed into a house and terrain while on approach about 2.5 km short of London-Gatwick Airport (LGW/EGKK), United Kingdom.
The aircraft was completely destroyed. Two people on the ground and 48 occupants perished, the remaining three crew members and eleven passengers survived with injures. (50 fatalities, 14 survivors)
The crash of Flight 701 is the seventh deadliest aviation accident on the UK soil. It is also the 33rd worst accident involving the Boeing 727.
Ariana Afghan Airlines Flight 701 departed Kabul on a flight to London-Gatwick. Intermediate stops were made at Kandahar, Beirut, Istanbul and Frankfurt. Prior to leaving Frankfurt the crew obtained the weather information of the London area. The RVR at Gatwick was 100 metres in freezing fog and no improvement was expected before 06:00 UTC the following morning. The visibility at Stansted was 2 km. The aircraft left Frankfurt at 00:36 UTC. After contacting London Airways at 01:13 the crew learned that runway 27 was in use at Gatwick and that the RVR was still 100 metres. The aircraft called Gatwick Approach at 01:27, reporting at FL50. The crew confirmed that they wanted to make an approach and were then cleared to 2,000 feet. The flight was vectored to capture the ILS. At 01:29 hrs the captain told ATC that in the event of a go-around he would proceed to the Mayfield NDB and then to London-Heathrow. Two minutes later, about 8 miles from touchdown the captain informed ATC that the aircraft was established on the ILS localiser. After the undercarriage was lowered the captain asked the flight engineer to warn him if the “stabilizer out of trim” warning light illuminated as it had done before while on approach to Frankfurt. After intercepting the glideslope the descent from 2,000 feet was started. At that point the “stabilizer out of trim” warning light illuminated. The engineer warned the captain who then saw that the autopilot was trimming the aircraft nose-down. Thinking this was wrong he disconnected the autopilot and re-trimmed the aircraft slightly nose-up. The aircraft crossed the ILS outer marker on the glide slope at 01:33 and the captain called for 30° flap, which the co-pilot set. As the flaps extended the rate of descent increased and the aircraft began to go below the glide-slope. The pilots remained unaware of the deviation from the glide-slope for some time. After the copilot called at 400 feet, the captain tried to trim the aircraft nose-up. There seemed to be no response. Both pilots then pulled back on the control column and at the same time the commander applied full power. The aircraft continued to descend and seconds later, as the nose began to rise in response to the application of elevator and power, it brushed through tree tops, knocked a chimney pot off a house, and then collided with tree trunks. This impact removed part of the starboard wing and the aircraft began to roll to the right. The aircraft broke clear of the trees and the starboard main wheels touched the ground in a field. The aircraft became airborne again, still rolling to the right, in a nose high attitude. Then the aft end of the fuselage collided with a house, which it demolished, and the aircraft disintegrated.
” The accident was the result of the commander inadvertently allowing the aircraft to descend below the glide slope during the final stage of an approach to land until it was too low for recovery to be effected. The following findings were reported:
– The deceptive nature of the weather conditions led the commander to an error of judgment in deciding to make an approach to Gatwick,
– The commander’s decision to conduct an approach was not in itself a cause of the accident,
– Incorrect flap configuration at glide-slope interception led to a temporary out-of-trim condition during the automatic approach and the illumination of the stabilizer “out-of-trim” warning light,
– The commander interpreted the “out-of-trim” warning light as indicating a possible malfunction and disconnected the auto-pilot,
– Out-of-sequence and late selection of 30° flaps from 15° while the-aircraft was being flown manually resulted in an increase in the rate of descent, causing the aircraft to go rapidly below the glide-slope,
– The commander did not become aware of the deviation from the glide-slope until it was too late to effect a full recovery,
– The pilot’s attention was probably directed outside the aircraft at the critical time in an attempt to discover sufficient visual reference to continue the approach rather than to the flight instruments,
– Monitoring by precision approach radar would have warned the pilots of the deviation in time, if corrective action was taken promptly, to avoid the accident.”