What happened
On September 21, 2013, a Robinson R44 II helicopter, registration PR-MOB, was involved in a loss-of-control accident in Planaltina de Goiás, Brazil. The aircraft, operated by AGM Caetano ME, was performing a vertical takeoff from a bus garage parking lot to facilitate the boarding and disembarking of passengers.
During the maneuver, the pilot was unable to maintain control of the aircraft, which lost lift and collided with the ground. The impact caused substantial damage to the skids and the tail rotor blades. Despite the impact, all four occupants—the pilot and three passengers—remained uninjured.
Prior to the accident, the flight had originated from Brasília (SBBR) with an intended destination of Planaltina (SWPV), but the route was altered in flight to the bus garage location. Witnesses noted that the pilot had attempted several unsuccessful vertical takeoffs before the final crash.
The investigation
CENIPA investigators examined the aircraft's weight and balance, the takeoff site, and the operational procedures. The investigation established that the takeoff site was not a certified landing area and did not meet the safety requirements stipulated by Brazilian aviation regulations (RBHA 91) regarding obstacle-free safety zones and approach/departure surfaces. Furthermore, the pilot failed to notify Brasília Air Traffic Control (APP-Brasília) regarding the change in landing location.
Technical analysis of the aircraft's mass revealed that the helicopter was operating significantly above its performance limits. At the time of the accident, the aircraft was at an altitude of approximately 3,400 feet with an ambient temperature of 30°C. The investigation determined that the aircraft was approximately 150kg above its maximum takeoff weight for out-of-ground-effect conditions. Additionally, the center of gravity (CG) was positioned forward of the manufacturer's established limits.
Findings
- The aircraft was operating with a total weight of approximately 1,260kg, exceeding the calculated maximum takeoff weight of approximately 1,110kg for the prevailing atmospheric conditions.
- The aircraft's center of gravity was outside of the manufacturer's specified limits.
- The takeoff and landing occurred at an unauthorized location that did not comply with regulatory safety standards for non-certified sites.
- The pilot failed to communicate the change in landing location to air traffic control.
- Inadequate flight planning and pilot judgment regarding weight limitations and the use of an uncertified landing site were the primary contributing factors.