Hong Kong Airlines has made it compulsory for their cabin crew to learn Wing Chun, a famous Chinese martial art which focuses on close-ranged battle.
It’s said that it will help the flight attendants to be better prepared against drunkards and troublemakers, which the airline encountered every 2-3 days.
I don’t think the lesson is of much use though; you can’t punch a passenger regardless, not in front of dozens of other on-flight customers. Besides, martial art is not something that can be learnt in a few hours, or even days. The situation might end up worse if the flight attendants attempt the techniques.