On 28 October 2008, an Airbus A330-200 (G-OJMC) being operated by Thomas Cook Airlines on passenger flight from Montego Bay, Jamaica to London Gatwick could not be rotated during its night takeoff until the Captain as PF had advanced the thrust setting to Take-off / Go-around (TO/GA) Mode after which rotation was achieved and the aircraft lifted off prior to the end of the runway and climbed away safely. Takeoff performance data, which was subsequently found to have been in gross error, had been obtained from Company Despatch when the on board Performance Manual could not be found.
The Investigation was delegated to the UK AAIB by the State of Occurrence. It was found that the operating crew had been supplemented by an additional on duty crew member. This pilot was an A330 line Captain and also a qualified A320/A321 Training Captain.
The Investigation found that during the pre-flight preparation, the flight crew had been unable to locate the aircraft performance manual and had therefore asked the Operator’s flight dispatch department in the UK to calculate the figures using the Airbus Flight Operations Versatile Environment (FOVE) computer system. The FOVE system is a Class 1 Hardware and Type 3 Software Electronic Flight Bag (EFB)
Both the aircraft commander and the co-pilot stated that they had independently received the same takeoff performance figures and these were entered into the Flight Management Guidance System (FMGS).
Neither the improbably low takeoff mass of 120,800kg supplied (the actual figure recorded on the aircraft load sheet was 210,183kg) nor the correspondingly low thrust settings and reference speeds were recognised as such by any of the pilots.
The Investigation was unable to identify the exact source of the data error made by the flight dispatch department but found procedural deficiencies in the Aircraft Operator’s methods for calculating performance using the FOVE system. These have since been addressed.
The flight crew were unable to explain to investigators why they did not recognise that the figures they used were outside the expected range, and it is considered possible that other crews, especially those less experienced or less rested, might be expected to make a similar oversight.
The Investigation found that a tail strike had been avoided in this event because the aircraft pitch attitude only reached a maximum of 9.5° whilst the main landing gear shock absorbers were compressed; whereas 11.5° of pitch would have been required for the tail to contact the runway.
The Investigation noted numerous other similar takeoff incidents and also that most current improvement work was focused on EFB procedural robustness and on reducing the probability of incorrect data input rather than on the addition of any additional safety net to actively monitor takeoff performance.
The Final Report of the Investigation was published on 12 November 2009 and may be read in full at the SKYbrary bookshelf: AAIB Bulletin: 11/2009, ref: EW/G2008/10/08
Two Safety Recommendations were made.
- It is recommended that the European Aviation Safety Agency develop a specification for an aircraft takeoff performance monitoring system which provides a timely alert to flight crews when achieved takeoff performance is inadequate for given aircraft configurations and airfield conditions.”
- It is recommended that the European Aviation Safety Agency establish a requirement for transport category aircraft to be equipped with a takeoff performance monitoring system which provides a timely alert to flight crews when achieved takeoff performance is inadequate for given aircraft configurations and airfield conditions.