Air Cadets on AEF in the back of Hercules will be upchucking BEFORE takeoff.
Many years ago I knew the Air Cadet Gliding Instructor who had his passenger turn towards him and say "I don't feel well Suurrrrr." Promptly depositing his half digested packed lunch and litre of Coke into the Instructors lap!
Personally I've only been airsick once - whilst travelling cattle class to Hong Kong in the rear of a Jumbo