Survival rates for people in Canadian helicopters that have crashed into water over the past three decades are the same as those around the world, a report published last year determined.
There were 46 civilian helicopters registered in this country that ditched in water from 1979 to 2006, resulting in 27 deaths among the 124 passengers and crew, according to an article published in the October issue of Aviation, Space, and Environmental Medicine.
That 78 per cent survival rate is the same as previously reported worldwide data.
The study indicates that ditching a helicopter into water is riskier than crashing on land due to factors such as inrushing water, the capsizing of the vessel and the ability of people to react under such stressful conditions.
The study into helicopter crashes — whose four authors include Chris Brooks of Survival Systems Ltd. in Dartmouth and Conor MacDonald and Michael Taber, formerly of Dalhousie University’s school of health and human performance — found that the situation can be especially perilous for workers headed to an offshore oil rig when a pilot ditches.
“Typically, many passengers have travelled overnight and are about to go on a two-week shift on the rigs,” the report says. “They are not quite as alert as they should be when the call comes. So it may take a few critical seconds for the gravity of the situation to dawn on them and this may be too late to do much.
“Warning time is critical for the crew and passengers to be able to take a breath of air before their heads go underwater since water comes in very quickly.”
Larry McWha, a retired colonel in the Canadian Armed Forces who flew Sea King helicopters for much of his career, said ditching in water is daunting for even well-trained military personnel.
“It’s probably the most difficult escape situation you can imagine,” Mr. McWha said.
“Unless you have gone through that training, it’s going to be very confusing and bewildering.”
Any passengers would have to wait until the rotors stopped turning before they could even start their escape from the helicopter, he said. Then they’d have to unstrap themselves and make their way to the same exits. There might be little light and a blast of inrushing, icy water as the helicopter possibly pitched to one side in the waves, he said.
“Anecdotal evidence from one U.S. navy pilot described it as like being hit suddenly in the chest with a fire hose,” the report says.