The Australian Transport Safety Bureau has issued a warning on hydraulic-boost servos for Robinson R44 helicopter operators.
The move comes following the ATSB’s investigation into a February 4 incident at Cessnock Aerodrome in which an 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 ATSB’s preliminary factual report into the accident 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 aircraft, 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 by phoning 1800 020 616. More details on the investigation can be found here.
A new Robinson R44 on display at Avalon 2011.
