AAIB investigation to Airbus A320-214, G-EZWE
Takeoff using incorrect performance data, Lisbon Airport, Portugal, 16 September 2019.
Summary:
Under international protocols, this investigation was delegated to the AAIB by the Gabinete de Prevenção e Investigação de Acidentes com Aeronaves e de Acidentes Ferroviários (GPIAAF) in Portugal.
During pre-flight preparations, both pilots completed a takeoff performance calculation for a takeoff from Runway 21 at Lisbon Airport. In calculating the performance, the crew believed they had selected the shortest runway length available (from the intersection with Taxiway S1) but had, in fact, used the runway full length (from Taxiway S4). The aircraft was cleared for takeoff from another intersection (Taxiway U5) and used performance calculated for the full runway length. The takeoff distance available from U5, although longer than from S1, was 1,395 m less than that used for the performance calculation, and the aircraft became airborne with only 110 m of the runway remaining.
As a result of this and previous, similar incidents, the airport operator renamed part of Taxiway S to have only one intersection on Runway 21 with the letter S.
The aircraft operator moved onto a newer software version for performance calculations in December 2019 which gives a pictorial representation of the runway. They also worked with the data supplier to change the menu for intersection selections for Lisbon Airport to eliminate any confusion over which position refers to the full runway length.
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