When a man weighing 200 pounds flies due east at 600 mph, he experiences a slight decrease in weight due to centripetal acceleration. Calculations show that if he turns around and flies due west, he would weigh approximately 201.6 pounds, which is about 1.595 pounds heavier than when flying east. This difference arises from variations in centripetal acceleration, calculated using the Earth's radius and the height of the plane. The discussion also humorously touches on the implications of weight changes for travel and sleep synchronization, and raises a question about weight on Jupiter, considering its larger size and shorter day length.