The heart of every plane is its engine. Pratt & Whitney has made some of the best engines ever built. Many of them are nicely displayed in this large hangar. Our thanks to Mr. John Zepp for his assistance and for showing us one of the newest engines. Mr. Zepp told us that the cost of an airplane engine is about a quarter of the cost of a plane. Charles Lindberg's engine cost $10,500, so his plane, the Spirit of St. Louis, was four times that or $42,000.