Incident Overview
On 17 October 2019, a serious incident occurred at Warsaw-Babice Airport (EPBC) involving two aircraft: a Tecnam P2006T, registration SP-MMB, and a Piper PA34, registration SP-CSL. The Tecnam was conducting training flights in the traffic pattern for runway 28L, crewed by a pilot instructor and a student pilot. Several aircraft were present in the pattern at the time.
Sequence of Events
While the Tecnam was on the downwind leg, the Piper crew reported overflying point PAPA en route to point ZULU. The Tecnam crew then reported their downwind position. At approximately 16:17 local time, as the Tecnam approached the third turn, its crew observed the Piper entering the traffic pattern without maintaining proper separation. During the third turn, the Tecnam crew saw the Piper behind them on a converging course. The Tecnam instructor radioed that they were turning base and that the Piper was entering the pattern, attempting to assert priority and creating a traffic conflict. The two crews exchanged information.
Both aircraft were twin-engine; the Piper was capable of higher speeds. The Tecnam crew believed the Piper would delay its entry into the pattern and continued the turn to base. The Piper instead continued ahead, overtaking the Tecnam and proceeding toward the final turn. The Tecnam crew lost sight of the Piper until they aligned with the runway, when they saw the Piper ahead of them. The estimated separation at that point was 30 meters according to the Tecnam crew, and 100 meters according to the Piper crew. The Tecnam crew informed the airport's Aerodrome Flight Information Service (AFIS) of the dangerous situation. The Piper maintained a higher speed in the pattern and, after reaching the final approach, executed a go-around for another circuit.
At EPBC, traffic pattern flights were required to follow a precise route, and the number of aircraft in the pattern was not limited. During periods of intense flight activity, entering the pattern was challenging.
Cause
The incident resulted from the Piper crew's improper assessment of the traffic situation in the traffic pattern.
Contributing Factor
A contributing factor was the large number of aircraft in the pattern, which complicated entry into the traffic flow.