What happened
On September 1, 2002, at approximately 07:07 UTC, a runway incursion occurred at Barcelona Airport involving two Boeing 737 aircraft. The first aircraft, a Boeing 737-300 with registration OK-BGQ (flight CSA 6656), was on final approach to runway 25. Simultaneously, a Boeing 737-400 with registration G-EZYP (flight EZY820) was positioned on the runway.
The sequence of events began when the air traffic controller (ATC) issued instructions to the crew of G-EZYP to line up and wait on runway 25. During this period, the ATC instructed the approaching OK-BGQ to reduce speed and provided a non-standard go-around procedure. At one point, the ATC instructed the crew of OK-BGQ to perform a go-around; however, shortly thereafter, the controller issued a landing clearance to the same aircraft.
Despite the presence of G-EZYP on the runway, the crew of OK-BGQ continued the approach and touched down at 07:07:32 UTC, passing over the area where the other aircraft was holding. The pilot of G-EXYP immediately protested the instruction, noting the danger of the situation. The controller was subsequently replaced during the incident.
The investigation
The CIAIAC investigation examined radar track data, Flight Data Recorder (FDR) information from OK-BGQ, and air traffic control communications. The investigation established that the aircraft OK-BGQ was flying a manual landing approach and that the autopilot was disengaged at 250 feet. The FDR confirmed that the aircraft's vertical trajectory was a continuous descent until touchdown.
Investigators also reviewed the communications between the tower and both flight crews. The investigation noted that the ATC had issued conflicting instructions, including an initial command for a go-around followed by a landing clearance while the runway was still occupied by G-EZYP. The investigation also looked into the use of language in communications, noting that the use of non-standard phraseology and the mix of Spanish and English contributed to the confusion.