What happened
On April 12, 2022, an Airbus A330-900, registration CS-TUL, was preparing for a scheduled flight from Luanda International Airport (FNLU) to Lisbon (LPPT). Due to ongoing infrastructure construction at the airport, the flight crew utilized intersection E for the take-off roll on runway 23.
During the take-off roll, the flight crew realized the end of the runway was approaching rapidly. In response, the pilot in command applied maximum takeoff power (TOGA). The aircraft reached rotation speed (Vr) at the very edge of the runway. During the rotation phase, the cabin crew reported observing significant dust outside the aircraft, a condition later confirmed by the air traffic control tower. The aircraft successfully became airborne and proceeded to its destination, where a detailed maintenance inspection was performed; no damage or injuries were reported.
The investigation
The GPIAAF investigation established that while the crew had performed and reviewed take-off calculations several times, they had failed to identify that the correct departure position was intersection E. Instead, the performance parameters were calculated based on the full length of runway 23.
Specifically, the crew had calculated for a Flex Temp take-off (85% N1). However, seven seconds after lift-off, the crew selected TOGA power (~94% N1) to compensate for the short distance. The investigation noted that the operator's fleet was not equipped with the second-generation Take-off Surveillance and Monitoring (TOS2) system, which is designed to alert crews if the expected lift-off distance is incompatible with the available runway length.
Findings
- The crew performed take-off calculations using the full length of runway 23 instead of the shortened distance available from intersection E.
- The use of incorrect performance parameters during take-off increased the risk of a runway overrun.
- The aircraft's fleet lacked the optional TOS2 technology, which could have provided a visual warning (T.O RWY TOO SHORT) in the MCDU scratchpad.
Safety action
Following the incident, the operator implemented several mitigation measures, including:
- Updating the Electronic Flight Bag (EFB) to improve the presentation of information regarding runway selection during construction periods.
- Conducting a feasibility study to retrofit the A330neo fleet with the optional TOS2 surveillance system.