The military has had a long history of cancelled aircraft. Some of them were promising. Others were ambitious, though sometimes impractical. But one thing about cancelled aircraft is that they spur discussion on what could have been had they seen service. These military planes could have had huge impacts on wars and civilian life, but for one reason or another never made it to active duty. Here are some planes I consider the best among cancelled planes.
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Douglas F6D Missileer
When the air-to-air missile was being developed, some people were excited about it. They thought it would be the be-all and end-all to aerial combat. Thus they decided that the carrying aircraft need not be maneuverable; the missiles would do the maneuvering. This was to be the F6D Missileer, an expansion of the F3D Skynight that carried only missiles. But the plane never even saw prototype stage. In Vietnam, analysts saw that aircraft needed to carry a gun in certain situations. But the missile carrier concept found its way into the TFX program, and eventually, the F-14 Tomcat.
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Perhaps the most interesting cancelled aircraft of all, the A-12 was to replace the A-6 Intruder. It would have been a flying triangle without any vertical surfaces, earning the nickname "Flying Dorito." The cancellation was due to cost overruns and failure to deliver much of the requirements on time without even showing even just a mockup of the aircraft. see more on McDonnell Douglas A-12 Avenger II
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The U.S. had its own interceptor project what was similar to the Arrow. It was unique for using the engines of the XB-70 Valkyrie, leading many to believe that it was an escort for the bomber. But writer Erik Simonsen says, it cannot match the range of the Valkyrie and its main target was Soviet jet bombers. If built, it would have been the heaviest fighter at the time. see more on North American XF-108 Rapier
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Avro Canada CF-105 Arrow
The Arrow was Canada's attempt at an indigenous interceptor aircraft, designed to take down Soviet jet bombers. Politics however was a significant factor in the cancellation of this aircraft. The cancellation alone led to the layoff of 14,000 Avro employees. The event was called Black Friday in Canadian history.