A cargo plane loaded with canaries is set to take off but the co-pilot has calculated the weight of the plane and its contents is just a few pounds over its maximum allowable takeoff weight. “No problem,” he tells the captain, “I’m going back to the cargo area. When you hear me yelling, go ahead and take off.” What was he planning to do?
Answer
The co-pilot was planning to make a lot of noise yelling, scaring the canaries into flying which would lighten the load enough for the plane to take off. The fuel burned during take-off would lighten the load enough for the birds to alight again after the plane was airborne. (The captain, however, knew this little trick wouldn’t work and taxied back to the loading area to have some canaries removed. He knew that the canaries were heavier than the air; they displaced from the closed interior of the aircraft and that their combined weight while flying would still be distributed to the aeroplane by air molecules)
