Incident Overview
On 12 July 2021, around 21:14 local time, a serious incident occurred at Jelenia Góra Airport (EPJG) involving a Jak-12M aircraft registered as SP-AAM. The aircraft was operated by Aeroklub Jeleniogórski and was being used for proficiency flights. The incident took place on the apron in front of a hangar, after the aircraft had landed and was maneuvering to park.
Aircraft and Operator
The aircraft involved was a Jak-12M, a single-engine tailwheel light aircraft. The operator was Aeroklub Jeleniogórski. The aircraft sustained minor damage: the paint on one propeller blade was scuffed. A parked Cessna 150 suffered damage to its rear fuselage and horizontal stabilizer when struck by the still-turning propeller.
Pilot Background
The pilot was a 51-year-old male holding a Private Pilot Licence (PPL(A)) with a single-engine piston land (SEP(L)) rating, valid medical certificates Class 2 and LAPL with VML limitation. His total flight time on airplanes was 57 hours 48 minutes, with 26 hours 24 minutes as pilot-in-command. He had 1,260 hours on gliders, including 600 hours as an instructor. On the Jak-12M, he had completed 20 flights total, of which 8 were solo.
Events Leading to Collision
The pilot had completed four proficiency circuits under an instructor's supervision. After the fourth landing, he began taxiing back to the parking area. As he approached the apron, he initiated a right turn to position the aircraft tail-first toward the hangar. Shortly after, he heard a radio command to "stop." In response, he attempted to brake by pressing the rudder pedals. This action was ineffective because the Jak-12M uses a brake lever on the control stick, unlike the Cessna 150 and PZL-104 Wilga he had previously flown, which have toe brakes. He then switched off the magnetos, but the propeller was still rotating as the aircraft coasted into the parked Cessna 150, striking its tail.
According to the pilot, before leaving the runway he had looked toward the hangar and noticed a winch on the apron, but did not see the parked Cessna. During the straight taxi to the hangar, forward visibility from the cockpit was limited, and he did not use recommended techniques such as "S-turns" or raising the seat to improve the view.
Damage and Injuries
No injuries occurred. The Jak-12M's propeller blade paint was damaged, and the Cessna 150's rear fuselage and horizontal stabilizer were damaged by the propeller strike.
Findings
The investigation identified two causes of the incident: 1) Improper taxi technique for a tailwheel aircraft, which prevented the pilot from seeing the area in front of the aircraft; 2) Ineffective brake application due to the pilot's limited experience taxiing the Jak-12M. A contributing factor was the restricted forward visibility from the Jak-12M cockpit while taxiing.