Description

On 11 August 2010, a Douglas DC8-63F being operated by Afghanistan-based operator Kam Air on a non scheduled cargo flight from Manston UK to Sal, Cape Verde Islands failed to get airborne until after the end of departure runway 28 during a daylight take off in normal visibility. The aircraft eventually became airborne and climbed away normally and when ATC advised of the tail strike, the aircraft commander elected to continue the flight as planned and this was achieved without further event. Minor damage to the aircraft was found after flight and there was also damage to an approach light for the reciprocal runway direction.

Investigation

An Investigation was carried out by the UK AAIB. It was noted that the aircraft operator carried out both international and domestic passenger and cargo flights. It had recently acquired the incident aircraft and one other of the same type and the incident flight was found to have been the first commercial task for the operator’s new DC-8 fleet. It was established that the aircraft had been chartered to transport a consignment of polo ponies from the UK to Argentina with only a refuelling stop at Sal.

It was found that a load and trim sheet had been prepared by the Flight Engineer which showed a TOW of 335,410 lb. The same person also prepared a takeoff data card which was presented to the commander when he arrived on the aircraft and which showed the (correct) higher TOW of 343,000 lb and take off speeds corresponding to this higher weight. It was noted that no crosscheck of the flight engineer’s calculations or takeoff performance figures had been made by any other crew member. The actual TOW was found to have been 25,700 lb above the maximum (runway limited) takeoff weight.

The departure was made with the aircraft commander as PF and with nine passengers on board - three positioning flight crew and six grooms and vets who were to attend the ponies during the journey. Rotation had been observed by persons on the ground to have been initiated near the runway end and a cloud of debris was seen to be thrown up from beyond the runway as the aircraft climbed away. The aircraft commander advised the Investigation that he had been aware of two jolts during the take off and had suspected that a tail strike had occurred.

Evidence of tail skid surface contact for a distance of 131m was found, beginning towards the end of the runway and continuing on the soft ground beyond. An approach light for the reciprocal runway was destroyed by the aircraft’s main landing gear.

Inspection at Sal showed that the tail skid energy absorber had deformed by an amount reported by the Operator to have been within the AMM limit such that no further inspections were required.

The flight crew advised the Investigation that they attributed the failure to cross check any of the Flight Engineer’s take off data calculations to “the commander’s absence from the aircraft, distractions and time pressure”.

The Investigation concluded that “the tailstrike most probably occurred because of a deviation from the correct rotation technique, probably an instinctive reaction on the part of the commander to the rapidly approaching runway end. The overweight takeoff was thus a major contributory factor, and the lack of recent aircraft handling experience is also likely to have contributed.”

It was also considered that the investigation had “highlighted a number of procedural failings by the flight crew, a lack of currency in line operations and a lack of operational oversight and control by the aircraft operator and the regulatory authority in the Islamic Republic of Afghanistan.”

The Operator was subsequently instructed by the Afghan Regulator to cease DC9 operations and all the associated DC8 flight crew licences, which had been issued on the basis of equivalent Gulf CAA licences, were revoked.

The Final Report of the Investigation AAIB Bulletin: 5/2011 was published by the UK AAIB on 5 May 2011. It contained four Safety Recommendations as follows:

• That the (Afghan) Ministry of Transport and Civil Aviation review its processes for the regulatory oversight of commercial aircraft operators based in the Islamic Republic of Afghanistan. (2011-006)

• That the International Civil Aviation Organisation establish an alternative to the ICAO Universal Safety Oversight Audit Programme (Universal Safety Oversight Audit Programme) procedure for those states, such as the Islamic Republic of Afghanistan, where security, or other, concerns prevent regular on-site auditing. (2011-007)

• That the International Civil Aviation Organisation conduct an aviation safety oversight audit of the Islamic Republic of Afghanistan. (2011-008)

• That the UK Department for Transport review their process for the issue of permits to aircraft operators where the ICAO auditing system does not provide an appropriate level of confidence in the State’s regulatory oversight. (2011-009)

Further Reading

• Runway Excursion
• Aircraft Load and Trim
• Loading of Aircraft Holds
• Cross-checking Process