What happened
On July 25, 2011, at 17:25 UTC, a Robinson R-22 helicopter, registration PT-HRL, was conducting a local instructional flight. The aircraft departed from Campo de Marte Aerodrome (SBMT) in São Paulo with an instructor and a student pilot on board. The flight was intended to last approximately 75 minutes.
The flight crew proceeded to a grassy area located at the 2nd Army Police Battalion in Osasco, SP, to perform ground maneuvers. During a demonstration of flight controls, the instructor was showing the student how to use the collective lever. As the collective was manipulated, the aircraft moved backward, causing the tail skid to strike the ground and break. This impact led to the tail rotor striking the grass, resulting in a loss of control. The helicopter subsequently rolled onto its left side.
The investigation
CENIPA's investigation established that the meteorological conditions were favorable for Visual Flight Rules (VFR). The investigation noted that the area used for the instructional maneuvers was neither officially approved nor registered for such operations. The crew members were found to have valid medical and technical certifications, and the aircraft was in compliance with airworthiness and weight and balance requirements. The investigation confirmed that the instructor was qualified and experienced, while the second occupant was a student in training.
Findings
- The primary cause of the accident was the breakage of the tail skid during ground maneuvers.
- The operation was part of a flight instruction session.
- The pilot's limited experience contributed to the occurrence.