Pilots of a Boeing MD-83 conducted an unauthorised approach to Kandahar, and failed to stabilise the aircraft, before it sustained serious damage in a runway wing-strike.
Spanish investigators have determined that the aircraft, operated by Swiftair, did not have operational approval for the GPS approach it performed to Kandahar’s runway 05.
The aircraft should have been in a stable approach configuration as it descended through 1,000ft, with an airspeed of 135-155kt.
But the MD-83 (EC-JJS) was still travelling at 192kt, says Spanish investigation authority CIAIAC, adding that it was above the glideslope and descending “well in excess” of the maximum rate of 1,000ft/min.
“The approach should have been discontinued and a missed approach executed,” it states in its findings into the 24 January 2012 accident.
CIAIAC says the pilots established visual contact with the runway 500ft above minimum and saw they were slightly to the right of the centreline.
Between them the pilots had logged nearly 5,500h on type but the captain, having more experience operating to Kandahar, took over the controls to fly the last part of the approach.
Precision-approach path indicator lamps were not functioning at the time, and the crew had to rely on visual references. Analysis showed the aircraft flew below the glideslope during the final 1nm before touchdown.
Although the pilots corrected the aircraft’s course to the left, says CIAIAC, the aircraft drifted left during the flare, “threatening to take them off the runway”.
The captain applied right roll and the outboard right wing struck the runway about 20m before the threshold, destroying five lamps. Some 3.6m of the outer wing structure was “significantly and permanently bent upward”, says CIAIAC, while the aileron and slats were badly damaged.
Investigators found that the cockpit-voice recorder had been overwritten, and could not provide data on the accident.
Swiftair was carrying out the flight from Dubai on behalf of South Africa’s Gryphon Airlines, which had a US government contract to transport troops. None of the 91 occupants was injured, says CIAIAC, adding: “Passengers were not really aware of the incident and disembarked normally.”