An uncorrected read-back error caused a serious runway incursion on a German airport, involving a military transport plane and an Airbus A319 passenger plane with the A319 passing over the transport plane at 400 ft altitude.
German Wings flight 8045 operated on regular domestic service from Zweibrücken Airport (ZQW), Gemany to Berlin-Schönefeld Airport (SXF). With 132 passengers and five crew on board the Airbus A319 (D-AKNN) taxied to runway 03 for departure. This involved back tracking on the runway and turning for a departure from runway 03.
While the Airbus was taxiing down the runway, the crew of a Transall C-160 transport plane contacted the tower. The airplane was about to depart on a local flight to drop skydivers. The crew requested a departure from runway 21, although runway 03 (in the opposite direction) was the active runway. This was approved by the controller by stating: “German Air Force 173, taxi holding point runway, correction, taxi holding point Alpha, runway 21.” This was confirmed by the Transall crew as: “taxi runway holding point runway 21 via Alpha”. The erroneous read back was not noticed by the controller.
About one minute later the German Wings A319 was cleared for takeoff: “A319, wind variable 1 knot, runway 03, cleared for takeoff.” As the A319 was commencing the takeoff roll, the Tower controller noticed that the Transall had entered the runway. He immediarely radioed: “German Air Force 173, hold position … 8045, break up”. By then the A319 had already reached a speed above V1. The pilot in command continued the takeoff and overflew the C-160 at 400 ft (122 m).
The A319 pilot later reported that he did not understand the command “break up”.
The German BFU concluded the following probable causes:
The runway incursion occurred because a C-160 Transall did not stop at the holding point 21 but lined up on runway 21 due to misinterpretation of the taxi clearance.
Contributing factors were the deviations from standard operating procedures (SOPs). These were:
- The take-off direction intended for and used by the C-160 Transall was contrary to the operating direction of the runway for all other take-offs and landings.
- The standard phraseology for radio communications was not consequently adhered to.
- The read-back-hear-back procedure was not consequently adhered to.
The wrong line-up on the runway could not be detected by the crews of the airplanes involved. Due to the elevation profile of the runway, the opposite airplane could not be seen or only to a limited extent.
The controller, too, could not see every airplane on the ground at all times due to the elevation profile of the runway.
- BFU report (PDF, in German)