More than eight months after a fatal helicopter crash near the Campbell River airport, investigators still cannot confirm what brought the aircraft down.
The TSB said the helicopter was certified, equipped and maintained according to existing regulations, but did not have a flight data or cockpit voice recorder, which was not required by regulations.
The Transportation Safety Board (TSB) is recommending mandatory lightweight flight recording systems be installed by commercial and private operators that did not previously require them.
On October 1, a Robinson R44 Astro helicopter with two pilots on board crashed just before 4 p.m. about three kilometres west of the Campbell River airport.
The crash left one woman dead and a man seriously injured.
In its report, the TSB said the right seat pilot, who had been demonstrating his ability to conduct slow flight manoeuvres for potential future employment, transferred control of the helicopter to the left seat pilot.
Soon after the transfer and close to the ground, the chopper began to spin to the right and after several turns, it hit some trees before falling vertically to the ground.
The left seat pilot was fatally injured, while the right seat pilot suffered serious injuries but was able to contact 911 with his cellphone about an hour after the helicopter went down.
Search and rescue teams arrived on the scene just after 6 p.m. and the surviving pilot was airlifted away from the site at 7:48 p.m and taken to hospital in Victoria.
An examination of the flight control and drivetrain showed no signs of disconnect or premature failure, and the engine was found to be capable of producing full power within normal operating specifications for that type of aircraft.
The TSB says there were signs of “slippage and wear” of the aircraft’s drive belts, with one strand burned completely through, but investigators could not determine how much damage, if any, occurred prior to impact.
Significant gouging damage was apparent to the engine-cooling fan’s tapered surface of the shaft and bearing assembly.
The bolts holding the fan wheel to the socket hub were loose and elongated, but the investigation was unable to determine if this played a role in the crash.