The Aviators: Eddie Rickenbacker, Jimmy Doolittle, Charles Lindbergh, and the Epic Age of Flight

by Winston Groom

What allows an aircraft to take off from the ground (or, in this case, the deck) is a factor called lift, which is a direct function of the speed of the airflow over the wings. Every plane has a takeoff speed—the speed at which it can become airborne—depending on atmospheric conditions. On a carrier, there is the added factor of the speed of the vessel, plus the speed of the wind, as the carrier will always turn into the wind to launch. In the experiment Duncan conducted with the B-25s, the speed of the ship was 20 miles per hour, and the speed of the wind was 25 miles per hour—a total of 45 miles per hour of airflow over the wings. Since the minimum takeoff speed of the B-25 was a low 68 miles an hour, the pilot had only to accelerate to about 23 miles per hour to get airborne. In fact, a takeoff by a 25,000-pound plane in less than 500 feet would have been impossible except from an aircraft carrier. Wind at sea, then, would be an important factor in the raid.