Safety Advisory Notice
To aerobatic pilots and instructors
All aircraft types do not spin and recover in the same way. Know your aeroplane type, what recovery techniques will work and what recovery techniques will not work.
On 23 June 2021, while conducting spin entry and recovery training from 5,800 ft above ground level, the Cessna A150M Aerobat did not fully recover from a spin to the left before impacting terrain.
Factors uncovered during the investigation
The aerobatics instructor was experienced in conducting spins, primarily in the Pitts Special aircraft type. However, it was likely that they had no experience in spinning a Cessna A150 Aerobat or any similar variant.
The instructor’s theoretical spin training provided to the aerobatic student pilot (and another student at the same time) did not include instruction on the recovery technique as prescribed in the Aerobat pilot’s operating handbook (POH). Further, the ATSB established that it was likely the instructor intended to practice 2 spin recovery techniques (Mueller/Beggs and PARE). The technique broadly known as the Mueller/Beggs recovery method, has been shown to not recover a Cessna A150 Aerobat established in a spin to the left. However, the PARE method was similar to Aerobat POH method, with less emphasis on the brisk full forward movement of the control yoke.
Safety advisory notice
AO-2021-025-SAN-001: The ATSB strongly encourages all aerobatic pilots and aerobatic flight instructors to be aware:
- the Mueller/Beggs method of spin recovery does not recover all aircraft types from a spin
- the Mueller/Beggs spin recovery method limitations should be emphasised during spin theory training
- the Mueller/Beggs method of spin recovery will not recover a Cessna A150 Aerobat or similar variants from a spin in some circumstances
- they should review the pilot’s operating handbook of the aircraft type that they intend to operate for the recommended spin recovery technique
- prior to doing spins in any model aircraft, pilots should obtain instruction and or advice in spins from an instructor who is fully qualified and current in spinning that model.
Read more about this ATSB investigation: Investigation: AO-2021-025 - Collision with terrain involving Cessna A150M, VH-CYO 5 km west-south-west of Peachester, Queensland, on 23 June 2021 (atsb.gov.au)