What happened
On October 4, 2010, during a period of moderate traffic at Prague/Ruzyně Airport (LKPR), a Boeing 737-800, registration OK-TVP, operated by Travel Servis a.s., entered active runway 13 without authorization.
The crew of the aircraft had received taxi instructions from Air Traffic Control (ATC) to proceed via taxiways H1, F, L, and runway 2 and to hold short of runway 13. The crew explicitly read back these instructions. However, while taxiing, the crew entered runway 13 behind a departing ATR aircraft (CSA724).
Because runway 13 was occupied by the Boeing 737-800, the controller was forced to instruct an arriving aircraft (callsign NAX3580) to perform a missed approach. Additionally, the controller instructed the arriving aircraft to deviate 15 degrees to the right to maintain separation from the departing ATR aircraft. This sequence of events led to a significant reduction in separation between the arriving aircraft and the departing ATR, with vertical separation dropping to 70% and horizontal separation dropping to 66% at different times.
The investigation
The ÚZPLN investigation examined radar records and radio communications from the air traffic control service. The investigation established that the crew of OK-TVP was aware of the departing ATR aircraft and the arriving aircraft on final approach, noting that TCAS indications for the arriving aircraft were between 1,100 and 1,200 feet. The investigation confirmed that the radio communications between the controller and the crews were clear and legible, and that the meteorological conditions did not contribute to the event.
Findings
- The crew of OK-TVP entered runway 13 despite having confirmed instructions to hold short of the runway.
- The runway incursion necessitated a missed approach for the arriving aircraft to ensure safety.
- The incident resulted in a major reduction in separation minima between the arriving aircraft and the departing ATR aircraft.
- The primary cause of the incident was human error, as the crew failed to comply with the ATC instructions provided.