Royal Canadian Air Force officials have lifted a suspension on a fleet of Sikorsky-made Cyclone helicopters after one of the aircraft, known as the Stalker 22, crashed into the Ionian Sea off the coast of Greece, killing six crew members. An investigation of the April 29 crash remains ongoing, but Canadian officials have determined that the helicopter’s autopilot system competed with the pilot as he tried to land aboard the frigate HMCS Fredericton.
The “unavoidable” crash occurred after a software “bias” informed the helicopter it wasn’t moving fast enough. The autopilot then pitched the helicopter’s nose downward and increased its speed, slamming it into the sea at a high speed.
Investigators believe the pilot attempted to manually override the computer and pull up from the swift dive. But given the aircraft’s low altitude, he had no time to assess the problem and regain control.
According to The Canadian Press, Lt.-Gen. Alain Pelletier, commander of 1 Canadian Air Division, suggested the problem was caused by a “series of events” and occurred within a “very narrow band” of flight operations that had not been previously tested or identified.
As a result, the Cyclone’s computer ended up “in competition with the inputs that the pilot was trying to actually induce in order to set the recovery,” Lt. Gen. Pelletier said in a briefing, according to The Canadian Press. “That element of conflict resulted because of the flight-control inputs.”
The Canadian Press also notes that the helicopter crash was the third known incident involving a Cyclone helicopter not responding as expected since 2015, when the first helicopters were delivered to the Canadian military.
In March 2017, a software problem in the flight control system of a Cyclone caused the aircraft to drop unexpectedly during a test flight. In February 2019, a Cyclone experienced a “hard landing” onboard the Navy’s interim support ship near Hawaii.
The April 29 Cyclone crash was the worst single-day loss of life for the Canadian Armed Forces in more than a decade.
Still, Canadian officials expressed confidence in the Cyclone helicopters, saying that the Cyclone “underwent a thorough certification process before confirming it met the requirements of the technical airworthiness program and being approved.”
Canadian military officials also refrained from placing blame on anyone for the deadly crash, saying that an assessment of the Cyclone’s autopilot could determine why it fails to behave as expected in some circumstances.
The Royal Canadian Air Force has cleared its fleet of Cyclones to return to the air almost immediately, according to CBC News. Their return to air will be supplemented with new training and flight manual updates to familiarize pilots with the potential problem and how to handle a malfunction if it happens. Military officials also imposed restrictions on certain flight activities that could cause the autopilot to disrupt the pilot’s intended flight.
Beasley Allen lawyer Mike Andrews focuses much of his practice on aviation litigation and currently represents families of Ethiopian Airlines flight 302 victims involving the Boeing 737 MAX aircraft. In addition to his Ethiopian Airlines crash clients, Mike has represented people seriously injured in a variety of aviation crashes, and the families of those killed in both civilian and military airplane crashes and helicopter crashes.