Helicopter

A helicopter carrying passengers suddenly looses engine power and the aircraft begins to decent. The pilot safely performs an emergency landing in water, and tells the passengers to remain seated and to keep the doors closed, stating that in emergency situations, the aircraft is designed to stay afloat for 30 minutes, giving rescuers time to get to them. Just then a man gets out if his seat and runs over to open the door. The pilots screams at him, "Didn't you hear what I said, the aircraft is designed to stay afloat as long as the doors remain closed?!".
"Of course I heard you", the man replied, "but it's also designed to fly, and look how bad that one worked out!!"