Sorry to hear about the accident. It could have been prevented. In our club, it is MANDATORY that all planes be secured in some manner prior to starting the engine. Some guys drive two posts into the ground and the airplane butts against them. Others drive a stake into the ground, and secure the airplane around the tail section to that stake. We also have a "can't fly alone rule", but that one is hard to enforce.

In lieu of the two above methods, a second person holding the plane while starting is acceptable - but NO ONE starts an engine with the airplane unsecured - and that rule is strictly enforced.

Even at that - there are times when someone will stick his hand into the prop for one reason or another. You can't win them all.