I'm very sorry for the accident that started this post. Unfortunately, that's what happens when a propeller contacts a person no matter what the power source. I've watched experienced boaters put their fingers into running propellers several times with similar serious results. These boats had obviously running gas or nitro engines. Some of these boats were on stands with propeller guards. It only takes a moment of carelessness. Quickdraw has
a picture of what happens when a gas engine driven propeller contacts a foot. The page also has some good advice. This boater was wearing boots. The newest chrome cobalt alloy propellers can be sharpened to the point that cuts can happen from just touching the leading edge.
At one time I was an advocate of safety loops. See below for my first P spec tunnel. However, the higher currents many electrics are now running make finding an acceptable connector difficult. The ones I've tried either have too much resistance as evidenced by melting the solder, or are too hard to disconnect. Other high current connectors are very expensive. Current speed controls seem to have made glitches rarer.
No matter what we do to engineer safety, there's no substitute for continuous vigilance. The T-shirt reproduced below says a lot, both about this and motivations for participating in model and full size boat racing.
Lohring Miller
Electric Tunnels 5.jpg
Safety Message.JPG