As part of our product development and improvement process, this past spring I attended an ice and swiftwater rescue class. This course was taught by Lifesaving Resources, a nationally recognized training company that is based right in Kennebunkport, ME. The class was approximately 1/3 classroom and 2/3 hands on practical in a pond at a local campground.
Normally, they use a chainsaw to cut a hole in the ice to simulate someone falling in through thin ice. However, the ice was so thin due to the warm weather that as soon as the class got onto ice, it collapsed all around us, dumping the entire class and instructors in the drink! Our first drill was self-extrication.
The rest of the day was a variety of drills using different equipment from a ring buoy to a standard stokes basket, to a purpose built rescue board from a company called MarSars.
All the evolutions involved two ropes. One was a safety line attached to the "victim" which was never actually used, similar to a belay line for a vertical rescue. The second was the actual line which would have been used in a rescue. This was a 7/16" Waterline x 300 feet. The extra diameter made it much easier for pulling than the 3/8, especially with gloved hands. We were all wearing exposure suits which have built in gloves which are very bulky and difficult to manipulate. In a real rescue, only the people on the ice would be in suits. Those on shore could wear more dextrous gloves.
The ropes are all pulled by hand, and there are no mechanical advantage systems used, so it's quite a simple setup compared to some rigging systems we deal with. The hand pulling is important because the rescuer and the victim can get snagged under the ice shelf and those pulling need to be able to feel if this happens, and not injure anyone.
The ropes all became coated in ice, making them difficult to pull. The instructors said that this is more of a training issue than during actual rescues because they do not typically do multiple evolutions, soaking the ropes and reusing them, normally they rescue a single victim then everything goes back to the station to dry out.