Casualties unknown

2011-08-24: ROBINSON HELICOPTER R44 II (9XR-SI) — Akagera Aviation — RW

RW

On August 24, 2011, a ROBINSON HELICOPTER R44 II (registration 9XR-SI) operated by Akagera Aviation was involved in an aviation accident near RW. Investigators recorded the probable cause as: The pilot's intuitive but incorrect response to the low rotor RPM warning, holding the collective steady instead of lowering it and increasing throttle, led to a main rotor stall. This summary draws on records from the Rwanda Aircraft Accident Investigation Department (AAID); 1 related events involving the same aircraft type or operator are linked below.

Sourcesthe Rwanda Aircraft Accident Investigation Department (AAID)Primary reportUpdated 1782291573Data APIEditorial standards

On August 24, 2011, a Robinson R44 II helicopter operated by Akagera Aviation crashed into terrain in Nyamagabe District, Rwanda, after the pilot did not follow emergency procedures for a low rotor RPM warning. The three occupants were seriously injured and the aircraft was destroyed.

Accident Overview

On August 24, 2011, a Robinson R44 II helicopter (registration 9XR-SI) operated by Akagera Aviation for a charter flight crashed shortly after takeoff in the Gatare Sector of Nyamagabe District, Rwanda. The aircraft was loaded near its maximum performance limits and operated in high-density altitude conditions with an approximate pressure altitude of 8,000 feet.

Sequence of Events

One minute after liftoff, during the initial climb, a low rotor RPM warning horn and caution light activated. The pilot attempted to maintain altitude by holding the collective pitch steady while trying to clear obstacles, rather than following the established emergency procedure of lowering the collective and increasing throttle. This intuitive but incorrect response led to a main rotor stall, resulting in a rapid loss of lift and control. The helicopter descended rapidly at low altitude and impacted the flank of the surrounding hilly terrain less than one kilometer from the takeoff site.

Injuries and Damage

All three occupants sustained serious injuries. The aircraft was destroyed.

Probable cause

The pilot's intuitive but incorrect response to the low rotor RPM warning, holding the collective steady instead of lowering it and increasing throttle, led to a main rotor stall.