Incident Description
On 5 June 2024, at approximately 17:15 LMT, a serious incident occurred at Warsaw-Babice Airport (EPBC) involving a Pipistrel Virus SW100 (registration SP-SIVA) and a SZD-50-3 "Puchacz" glider (registration SP-4111). The airplane pilot, holding a PPL(A) license, was conducting a flight from Nadolna to EPBC. At the time, glider operations were in progress at the airport.
The airport was using two parallel runways: RWY28R for gliders and RWY28L for other traffic. According to information from the AFIS coordinator, the airplane pilot performed a left circuit to RWY28L and then turned onto final approach. However, during the last turn, the pilot flew across the approach axis of the assigned runway, continuing into the axis of the parallel RWY28R. At an altitude not exceeding 100 m AGL, while in the fourth turn of the circuit, the airplane passed directly in front of the glider, which was on final approach. The glider instructor estimated the separation distance at approximately 10 meters. The instructor immediately took control, closing the air brakes. The airplane ended up below the glider, slightly ahead. Due to the glider gaining speed, both aircraft again came into very close proximity. Eventually, both landed on their assigned runways.
Neither crew observed the other before the incident. The airplane pilot stated that he did not receive information from the AFIS coordinator about glider traffic over the airport.
Weather conditions were not a factor: light westerly wind and CAVOK conditions.
Causes and Contributing Factors
The investigation identified the following causes and contributing factors: 1. Improper planning and execution of the south circuit to RWY28L by the airplane pilot, resulting in entry into the approach zone of the parallel runway in use – failure to maintain the intended rectangular flight path. 2. Lack of observation and anticipation by the airplane pilot. 3. Excessive speed during the fourth turn of the circuit, which hindered the pilot's coordination of the turn and caused it to "stretch" outward into the approach zone of the parallel runway. 4. Lack of observation and intervention by the glider flight director, who likely did not monitor the traffic situation as the inbound airplane incorrectly executed its turn, dangerously approaching the glider. 5. Lack of proper visual scanning by the glider crew (instructor and student), who likely focused on the approach and did not notice the approaching airplane.
Preventive and Safety Actions
Immediately after the incident, with the involvement of the glider flight director, both parties jointly analyzed the event. The airplane pilot acknowledged his errors and requested additional training flights. No safety recommendations were issued.
Commission's Commentary
The airport operates an Aerodrome Flight Information Service (AFIS) that coordinates arrivals and traffic in the aerodrome traffic circuit. AFIS provides information (including traffic information) to flight crews but does not provide separation. Due to high traffic volume, especially from glider operations, two parallel runways are used, separated by approximately 150 m. Glider traffic uses the grass strip on the north side and communicates on frequency 122.305 MHz (Babice Radio), while AFIS operates on 119.118 MHz (Babice Informacja) and monitors the glider frequency. The glider flight director can issue instructions to participants to ensure safety, but the primary responsibility for maintaining safe distances in uncontrolled airspace lies with the pilot-in-command. The commission emphasized that crews must maintain proper visual scanning, especially in the aerodrome traffic circuit, as other aids are supplementary. It also reminded that gliders have right-of-way over powered aircraft on approach and that overtaking on final approach is prohibited.