Finally, about 1960, he decided to stop researching and start producing an aircraft that could be certified by the Federal Aviation Agency. The result was the CCW-5 (Custer Channel Wing, 5-passenger). He has two of them, a prototype, which is a rebuilt version of the old Baumann Brigadier, and a production model, which is practically a hand-built version of the prototype with several improvements. I flew both of them, and I flew the new production model on its fifth flight when it had less than two hours time on it.

Before describing these flights, let's go over Custer's ideas again, from a more scientific viewpoint. After visiting Hagerstown, I stopped off at the Devore Engineering Service on Long Island. They are FAA designated engineering consultants who studied the CCW to make the necessary tests and reports for government approval. They translated Custer's rough explanations into engineering terms for me and they are retranslated here in layman's language.

A conventional airplane gets 80 percent of its lift from the upper surface of its wing. The air is static but, as the wing moves through it, it is displaced above and below the wing. As it is displaced, it speeds up to get back where it was. Following the law of physics, as it speeds up it lowers the pressure. The wing is built so that the air moves faster above the wing than below it, causing a greater pressure loss on the upper surface. The difference in pressure gives it its lift.

Now, if you placed a propeller behind the wing, it would speed up the air across it even more. But, if the propeller hub were centered on the trailing edge, the prop would be pulling the air off equally above and below the wing, cancelling any advantage.

What Custer has done, in effect, is to move the propeller above the wing so it pulls the air only from the upper surface. The he wrapped the wing half-way around the propeller to maximize the advantage.

Custer speaks of creating a vacuum in this channel, but it is never really true. However, in engineering terms, he has made a breakthrough in raising the lift coefficient of about 1.5. With huge flaps, slots and other auxiliary equipment, some can raise it to 3. The Custer Channel Wing has broken through to an unheard of lift coefficient of 5.

The CCW-5 is too heavy (4200 pounds) for its power (two 260-horsepower engines) to rise vertically "like a cork in water," although some of the earlier, lighter versions have done it. However, it is definitely a STOL, even though its power-to-weight ratio is about the same as conventional twin-engine aircraft that require about 3000 feet of runway. continue...