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Survival Research

In an offshore helicopter ditching or crash, passengers and crew face two time-critical dilemmas: getting out of the aircraft, then surviving the sea.


March 5, 2015
By Rick Adams

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In an offshore helicopter ditching or crash, passengers and crew face two time-critical dilemmas: getting out of the aircraft, then surviving the sea.

A significant number of accident deaths are not from impact injuries, but rather are by drowning, either because people cannot exit the submerged aircraft or, if they manage to do so, they aren’t able to apply life-sustaining techniques long enough to be rescued. In the UK Civil Aviation Authority’s CAP 1145 report on ditchings and water impacts from 1976-2012, nine accidents were deemed survivable. Of 38 fatalities in those accidents, “31 failed to escape from the helicopter . . . the main cause of death was drowning.” Six of the seven who escaped “then perished in adverse sea conditions before they could be rescued.”

In the Cougar 491 crash in 2009, 55 km off St. John’s, N.L., 17 of the 18 souls onboard died inside the aircraft. Two life rafts were empty. One woman was floating dead on the water. Only one passenger – an experienced sailor – escaped and survived.

Research underway at Falck Safety Services Canada (FSSC) in Mount Pearl, N.L., is taking a scientific look at two heretofore unexplored subjects:

The force required to open a push-out window

The effect of wave patterns on sea survival skills training

The projects are sponsored by the Research & Development Corporation (RDC), a crown corporation whose mandate is arm’s-length investing with potential long-term economic benefit for Newfoundland and Labrador, where the offshore oil and gas industry represents about 30 per cent of GDP.

The projects are co-funded by the industry’s Petroleum Research Newfoundland and Labrador organization, which includes backing from Chevron, Exxon Mobil, Husky Energy, Statoil, and Suncor. The first study focuses on the force required for a passenger to push a pop-out window, which is not considered an “emergency exit” by regulation but which may be a “supplementary” egress option.

Paul Sharp, a 23-year veteran rig scaffolder who survived the August 2013 North Sea Super Puma crash that killed four, described his attempt to escape through such a window after the helicopter crashed, filled with water, and inverted: “As soon as my head was covered with water, I looked down and pulled the tab on the window, and it just came to bits in my hand. So I hit it with my elbow a couple of times. Nothing. And then I punched it – I think I punched it three times – and all of a sudden it went pop and away it went."

Regulations say exits should not require “excessive force” to open, but the amount of force is not defined, according to project director, Michael Taber, Falck senior research scientist and an adjunct professor at Brock University. “What’s excessive might be different for you and me and for someone else.”

Using an S-92 aircraft and a specially designed “force plate” with four force transducers, FSSC’s research team will measure how much force it takes 50 people of various anthropometries (body dimensions) to open a window. Using the data to create a baseline math model, the researchers will repeat the force plate tests in a Survival Systems Ltd. simulator which can be immersed in a pool and rotated to 90-degree, 120-degree, and full 180-degree inverted positions for evaluation of both dry and wet conditions. Passengers face an additional dilemma in helicopters with hydraulic crash-attenuated seats (or “strokers”), which can descend several inches from their original position, potentially reducing the leverage a person has to push on a window. The second project will use a computer-controlled “wave ball” from Belgium’s Wow Company in a 60- by 40-foot pool to generate five simulated wave patterns of different magnitudes, including one-metre waves, slow-roller waves, 80 kph winds, driving rain, sea spray, “confused seas,” and sound effects. The purpose is to analyze how offshore workers best acquire and retain water survival skills such as keeping their airway clear and proper positioning in the water.

“You can train and train and train, but how do you respond in the actual environment?” Glenn Janes, CEO of RDC, asks. “Is that training innate or, if it’s not, how do you make it as close to innate as you possible? It’s one thing doing it in a simulated world and practicing – it’s very different when you’re put under the stresses and strains of the real world.”


Rick Adams is Chief Perspectives Officer of AeroPerspectives, an aviation communications consultancy based in the south of France, and is Editor of ICAO Journal. He has been writing about technology and training for 30 years.


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