I'm told this month's Mensa publication contains these hoax-related questions allegedly asked by Mensans.
From one person:
1. The tremendous height of the Saturn V launch vehicle was attributed to the amount of fuel needed to escape Earth's gravity. Given the fact that the moon's gravity is 1/6th that of the Earth, you'd need something 1/6th the height of the Saturn V to blast off from the moon. So how did the Eagle lift off?
2. Once achieving escape velocity when leaving the Earth, the Apollo would need to lose 5/6th of its velocity in order to be captured by the moon's gravity and swing into orbit. The spacecraft is moving at a velocity that prevents the Earth's gravity from pulling it back down - so unless they "put on the brakes" they certainly aren't going to be captured by the moon's gravity. However, all three stages of the Saturn V had been dropped - only the LEM remained.
3. How do humans survive at the top of a rocket? The space shuttle is fairly well isolated from the heat of its boosters, but no so with Saturn and its command module. At launch they had to spray lots of water on the launch pad to keep the concrete from cracking. Metal is a great conductor of heat. What kept the astronauts cool? Did they have a zillion air conditioners in the command module?
And from a different person:
4. Since studies estimate that the walls of the Apollo craft would have to be between six to eight inches thick with lead, how did we manage to send our astronauts through the Van Allen radiation belts without them receiving lethal doses of radiation? The Apollo craft walls were merely millimeters thick.