Xsm-73 Bull Goose
Photo Source: USAF

Canceled military aircraft projects was such a fascinating subject that I decided to write another article about some more of these canceled U.S. projects. There are a lot of these that most people never heard of and it is amazing how some of these things were the forerunners of even more advanced craft. There are a lot of different ways to approach stealth besides trying to make a plane undetectable by radar and the Xsm-73, also know as the Bull Goose, was a device that used an alternate method. That method was to fly a remote controlled drone into enemy territory that would look like a bomber on radar. It was the opposite of what we do today. The project was started in 1952 by Fairchild. What it actually was, was a decoy missile that looked like a plane. The US Air Force had planned to purchase over 2,300 of these missiles after first purchasing 53 for testing. In 1958 the program was canceled due to the fact that the missile could not make itself look like a B-52 on radar. Some missiles had been produced starting in 1957. The total number of flights that were made were 15, not counting dummy booster launches. These were conducted between March 1957 and December 1958. When the missile was produced it was known as the SM-73.

XFV-12
Photo Source: USN

In 1977 Rockwell built the XFV-12. This was another plane that was trying to sell the idea of vertical takeoff and landing to the navy. I guess if someone could develop a plane that had all the attributes of a great interceptor and still be able to land without needing a runway, it would be perfect for an aircraft carrier and even other smaller ships. The Hawker Siddeley Harrrier had already conquered VTOL, but it was a subsonic plane and the Rockwell plane looked far superior when one looked at its specs. Try as much as Rockwell did, they couldn't seem to get the plane to produce enough thrust for vertical flight. It was strange because they even installed an engine that had far more thrust than the empty weight of the plane, yet they still could not obtain that vertical flight. The competition was finished and the Marines went with the Harrier, which by the way turned out to be the only successful V/STOL plane in those days, which meant it could obtain vertical takeoff and landings and also fly horizontally like a conventional plane. The XFV-12 was canceled in 1981 and only 2 were built.

Thunderwarrior Project
Graphic Source: USAF

The Republic XF-103 Thunderwarrior was a project to develop a fast interceptor that could destroy incoming Soviet bombers. The project started in 1949 when the United States Air Force stated they wanted an advanced supersonic interceptor for the Air Defense Command. In 1951 three designs were selected for study. Republic had submitted the AP-57. Remember we are talking about 1951. The Republic design called for a plane built out of titanium that could reach speeds of over Mach 3. That is 3 times the speed of sound. The specifications called for the plane to be able to reach at least an altitude of 60,000 feet. By 1953 the mockup was built. In June 1954 there was a contract for 3 prototypes. There were problems not only with working with titanium, but also problems with the Wright J67 engines. It was almost impossible to pass Mach 2.5 at the time, because the blades in the engine turbines would get too hot. There were some aircraft that actually reached Mach 4 at this time, but these planes used ram jet engines and they had their own set of problems, including consuming huge amounts of fuel. This problem was overcome when an engineer mounted a turbojet engine with a ramjet engine behind it. The turbojet would run at lower speeds and be turned off when the ramjet was turned on for higher speeds. This system was used on the Republic RF-84F. The AP-57 was canceled at the mockup stage.

Airgeep
Photo Source: Public Domain

The army is always looking for ways to move soldiers around in a speedy manner. Piasecki Aircraft made an attempt to design a sort of flying jeep. It was classified as an experimental rotocraft and really looked strange. The contraption made its first flight in 1962. It had 2 tandem three blade ducted rotors that two people sat between. Not exactly a mass people mover. The engine had been upgraded from the original 2 piston one before making its first flight. The final prototype had a pilot, gunner and seats for 3 passengers It was initially called the Model 59K Skycar, renamed to Airgeep and designated by the army as VZ-8P. It was considered to be a vehicle that operated close to the ground, but could achieve altitudes of several thousand feet. After testing it for awhile, the army felt that it was not suitable for the battlefield and decided that helicopters were the way to go.

F-107
Photo Source: USAF

The military conducted a design competition for military aircraft in the 1950s. North American Aviation entered their F-107 fighter bomber. The plane made its first flight in 1956 and was retired in 1957. Only 3 of the planes were ever built. The plane was an evolutionary design of the F-100 Super Sabre Jet. It had a recessed weapons bay and 6 hard points underneath the wings to mount various weapons on. The big scoop on top of the aircraft controlled the amount of air that was directed to the engines. This system of air induction was extremely successful even though the plane itself was not adopted. The system was redesigned in the future and placed in a better position on a plane and was used on the F-16, A-6, XF-108 Rapier and XB-70. A shock wave was created when launching certain weapons that prevented proper launches and interfered with the pilot's ejection system. The plane hit Mach 1 on its first flight in September 1956. It hit Mach 2 in November 1956. It had successful test flights and the plane performed close to the Republic F-105 that was finally selected over it. Its speed was officially listed at Mach 2+. It was capable of carrying about 10,000 pounds of bombs. Two aircraft survive of the three prototypes.

DH-4 Heli-Vector
Photo Source: US Army

As I said previously, the US Army is always looking for ways to move soldiers around quickly. The HZ-1 Aerocycle, which was also known as the YHO-2 by the army and by the manufacturer as the DH-4 Heli-Vector was a sort of one man inverted helicopter. I say inverted because you flew it by standing on a platform above the blades. If you ever fell off, you would be sushi after the blades got done with you. It made its first flight in late 1954 and was intended to be a very easy to fly device for people with little or no experience. It was found that the machine was almost impossible to operate by untrained soldiers. After it crashed several times the project was abandoned after only 12 of these devices were built. You were supposed to be able to steer this device by simply shifting your weight. The developers felt that it was similar to the principle of riding a bicycle. The strange part of all this is that before the device was given to soldiers to test it, the testing program had been considered a success.