Operators of Robinson R44 helicopters are being advised to inspect the security of their helicopters' hydraulic-boost servos following a fatal accident at Cessnock Aerodrome, NSW.
On 4 February 2011, a Robinson R44 Astro helicopter crashed after part of the aircraft's flight controls separated from the hydraulic-boost system during circuit operations. The pilot survived, but the flight instructor and a passenger died in the accident.
The Australian Transport Safety Bureau's (ATSB's) preliminary factual report, released today, reveals that a bolt securing part of the flight control system had detached, causing loss of control of the helicopter.
The preliminary results of the investigation have prompted the ATSB to urge operators of R44 hydraulic system-equipped helicopters to inspect and test the security of the flight control attachments on their R44 helicopters, paying particular attention to the connections at the top and bottom of the servos.
A hydraulic-boost servo makes it easier for the pilot to handle the flight controls-similar to power steering in a car.
Operators who find anything unusual on inspection of R44 flight controls are asked to contact the ATSB on 1800 020 616.
The investigation is continuing.
The ATSB will release a final investigation report within 12 months.
More information on the investigation is available on the investigation page AO-2011-016.