What happened
On August 12, 2020, three aircraft were operating in the vicinity of Warsaw Chopin Airport (EPWR). The traffic consisted of a Cessna 150 (SP-HMN) performing a visual approach, a Cirrus SR22T (SP-AMD), and an Embraer ERJ195 (SP-LNM) operating under IFR.
Initially, the tower controller cleared the Cirrus SR22T for an approach and landing on runway 11. Meanwhile, the Cessna 150 was instructed to extend its downwind leg. However, the crew of the Cessna 150 performed a third turn instead of extending the leg, which altered the established traffic sequence. To manage the changing situation, the controller reordered the arrivals, clearing the Cessuna 150 to land first and assigning the Cirrus SR22T as the second arrival. Crucially, the controller did not cancel the existing landing clearance for the Cirrus SR22T, only informing the crew of the Cessna 150's movement.
As the Embraer ERJ195 approached runway 11, the controller provided information regarding preceding traffic but did not instruct the crew to reduce speed. After the Cessna 150 vacated the runway, the controller cleared the Cirrus SR22T for a landing with a fly-over to prevent runway occupancy delays. When the Embraer ERJ195 was approximately 1 NM from the runway threshold at 800 ft AMSL, the controller issued an instruction to initiate a go-around. This instruction was issued too late, as such maneuvers should typically be communicated before the aircraft is within 2 NM of the touchdown point.
The investigation
The investigation focused on the timing of the go-around instruction and the controller's management of the traffic sequence. The commission examined the use of phraseology and the impact of the Cessna 150's deviation from its assigned flight path on the subsequent arrival sequence.