Pilots’ memories led to improper decisions during takeoff: report

• Memories of past flights led military pilots astray as they tried to avoid an accident during an aborted takeoff two years ago that badly damaged an Aurora aircraft, says a safety report released Wednesday.

The military’s Directorate of Flight Safety says the captain spotted birds ahead as the reconnaissance plane roared down the tarmac at the Greenwood, N.S., air base on Aug. 27, 2015, destined for a patrol over northern Canada.

However, the report says the captain took too long to decide whether the flock warranted an aborted takeoff.

The document says the captain’s mind was considering a bird strike during a prior flight of the patrol aircraft, rather than reacting to the situation at the time.

“It’s quite strong in humans that you’ll revert to a previously learned behaviour that has been there for years,” said Lt.- Col. Martin Leblanc, the directorate’s chief investigator, in a telephone interview.

By the time the captain — who was the co- pilot but also the senior officer on the flight — called out a key warning code, the plane was going about 246 km/ h, which the report says makes ending the takeoff much more hazardous.

“By that point, they were too fast ... essentially they should be flying at that point,” said Leblanc.

At about 100 metres before the end of the runway the Aurora went off the tarmac, the nose gear collapsed and the No. 3 propeller broke from its engine. A flight engineer injured his head on a console and there were several other minor injuries.

Leblanc added he could understand the captain’s concern about a flock of birds because they can represent a risk to the aircraft, and added the pilot just had seconds to process the situation.

“Humans are fallible; we’re not robots,” he said.

The report also says the mind of the first officer flying the plane “likely reverted” to his days as a jet pilot flying the Royal Air Force Nimrod, as he tried to rapidly throw all of the turboprop engines into reverse — which resulted in only two of four propellers responding and the aircraft being thrown off balance.

The report described that decision as a case of the pilot going to “previously learned behaviour when stressed, instead of attempting to modify his or her reaction based on the circumstances.”

The flight directorate said while jet aircraft throttles can be rapidly reversed, the Auroras require a slower process to put the propellers into reverse when they’re going at high speeds.

The proper procedure is to wait for several lights to come on indicating the props are ready to be put into reverse.

Leblanc said two of the engines were locked, while the engines on the other side went into reverse, causing the aircraft to veer off the runway.

The report also says that special handles, referred to as “E- handles,” might have been pulled to shut down the engines, but this procedure wasn’t followed properly.

The i nvestigators also concluded that hydroplaning of the aircraft’s wheels played a role, and recommended that improvements be made to allow more runoff of water from the military runway.