From the Planes You’ve (Probably) Never Heard Of Department of Wingspan, we bring you the Cornelius XFG-1. There is an old adage that says necessity is the mother of invention, and there have been many cases where sudden need has provided some truly magnificent aircraft. The Cornelius XFG-1 was not one of them.
When the United States went to war against Japan following the attack on Pearl Harbor, they faced another enemy that was almost as difficult to overcome as the Japanese military: the vast distances of the Pacific Ocean. Before the campaign of island hopping moved American air bases closer to the Japanese homeland, bombers simply didn’t have the fuel capacity necessary to reach Tokyo and return to base. The famous Doolittle Raid of 1942 saw North American B-25 Mitchell bombers take off from the deck of the USS Hornet, but then continue on to mainland China, where many of the bombers crashed and their crews were killed or captured. But, if you couldn’t put enough fuel on board the plane, why not bring an extra fuel tank along for the ride? That was exactly the idea behind the Cornelius XFG-1.
Since the 1920s, inventor George Cornelius had been experimenting with gliders of different design, and one of his early designs was the Cornelius Mallard, a radical aircraft that featured a forward swept wing, vertical stabilizer, but no horizontal stabilizer. The functions of the horizontal stabilizer, or elevator, were carried out by elevators placed close to the fuselage, while ailerons farther out on the wing performed their usual function. A forward-swept wing, in itself, is not a terrible idea. Since the air flow over the wing moves towards the fuselage rather than towards the wingtip, the design helps reduce the chances of a wingtip stall inherent in traditionally swept wings. However, as the aircraft yaws from side to side, the retreating wing loses its sweep and creates more drag, leading to greater instability. Cornelius claimed that the Mallard, which formed the basis of the XFG-1, was both stall-and spin-proof, though experience with the larger XFG-1 would prove otherwise.
Not only was the XFG-1 a radical design, the entire concept was somewhat harebrained as well. The idea was that the unpowered XFG-1 would be filled with 764 gallons of aviation fuel and towed behind the bomber. Once all the fuel was transferred to the bomber, the glider would be released and allowed to crash on its own. The bombers would then have sufficient fuel to reach Japan and return to base. However, ditching the flying fuel tank was a rather wasteful proposition, so Cornelius developed a piloted version. Once released from the bomber, the glider would then be flown safely to the ground. However, it was never entirely clear exactly where the pilots were supposed to land their flying drop tank. Behind enemy lines? In the Pacific Ocean? Needless to say, there were probably very few pilots who would volunteer for such a mission.
Cornelius built two prototypes of the XFG-1. The glider took its maiden flight in 1944, and the two prototypes completed 32 test flights. However, despite Cornelius’ claim to the contrary, the XFG-1 was anything but spin-proof and, during one of the test flights, the first prototype entered an unrecoverable spin and crashed, killing the pilot. By the end of the testing program in 1945, the Allies had moved close enough to Japan that the XFG-1 was no longer needed, so the US Army Air Forces dropped the idea. Cornelius was undaunted, though, and continued to develop the concept, though he eventually gave up after the war when the USAAF began to develop dedicated refueling aircraft.
(Photo authors unknown)
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