Event Summary
On 20 May 2019, at 07:23 UTC, a serious incident involving two Boeing 737-800 aircraft occurred at M.R. Štefánik Airport (LZIB) in Bratislava, Slovakia. The aircraft involved were OK-TVO (Smartwings, Czech Republic), executing an ILS approach to runway 31, and EI-FOO (Ryanair, Ireland), awaiting takeoff clearance on the same runway.
Sequence of Events
Earlier, flight KLJ3076 had landed on runway 31 and vacated slowly due to delayed taxi instructions from the aerodrome controller (EC TWR). After KLJ3076 vacated, EC TWR cleared EI-FOO for takeoff. At that moment, OK-TVO was 1.3 nautical miles from the runway threshold. The approach controller had previously instructed OK-TVO to reduce speed when it was at 2.8 NM, contrary to regulations prohibiting speed adjustments inside 4 NM.
At an altitude of 400 feet, the OK-TVO crew observed EI-FOO beginning its takeoff roll. No instruction was issued by the tower for either aircraft. The OK-TVO crew initiated a go-around and turned left to avoid the departing aircraft. EI-FOO continued its takeoff normally.
Investigation Findings
The investigation determined that the controller underestimated several factors: tailwind, wet runway with standing water, and the slow runway vacation by KLJ3076. The controller's indecisiveness and inaction contributed to the serious incident. Specifically, the controller failed to issue a "hold position" or "go around" command, and violated the regulation prohibiting speed adjustments within 4 NM of the threshold. The investigation also noted that the controller could have requested KLJ3076 to vacate via a suitable taxiway to expedite operations.
Contributing Factors
The analysis highlighted that the aerodrome controller did not ensure the required separation between the arriving OK-TVO and departing EI-FOO. The controller allowed OK-TVO to cross the threshold while EI-FOO was still on the runway. The OK-TVO crew acted appropriately by executing a non-standard go-around based on visual observation and radio monitoring.
Conclusion
No injuries or damage were reported. The occurrence was classified as a serious incident due to the reduction in separation minima. The primary contributing factors were the controller's indecision, inaction, and non-compliance with applicable regulations.