The program metaphorically took off in 1958. The Air Force invited the National Advisory Committee for Aeronautics (the NACA, NASA's predecessor) to participate in what it was calling the ‘multipurpose manned bomber' program. Months of negotiations ended with each agency doing what it did best. The NACA would use its decades of aeronautical research to build the glider and the Air Force would add the firepower; proving the vehicle's flight worthiness would come before any dropped bombs. But this division left Dyna-Soar the center of an inter-agency conflict: should the first vehicle be a military prototype or a research aircraft?
To streamline the program, Dyna-Soar was subjected to a series of revisions early in 1959. The weapons system was deemed more important than any non-military applications, so it was labeled a military prototype.
But this decision was reversed two months later and suborbital hypersonic flights took precedence over military systems. This new arrangement lasted only a month before military application again became Dyna-Soar's top priority. By the end of 1959, Boeing had the contract to build the actual glider and the Martin Company had the contract to build the booster.
But this didn't solve the problem of Dyna-Soar's uncertain purpose. In fact, contracts yielded more program revisions that gave Dyna-Soar another possible outlet: it was a good candidate for America's first spacecraft.
In 1960, the Department of Defense jumped onto the Dyna-Soar train, endorsing the vehicle for both suborbital and orbital flights. When Yuri Gagarin orbited the Earth a year later in April 1961, the DOD redoubled its support, committing an additional $100 million to Dyna-Soar in the FY 1962. Boeing responded with a new schedule, aided with secure funding, that promised to fast track Dyna-Soar to orbital flights without a suborbital stopover.
But not everyone was on board with this plan. U.S. Air Force General Bernard A. Schriever wanted to see more military uses for Dyna-Soar, so he subjected the program to another study. Once again, Dyna-Soar's path was redirected, putting the emphasis on its military uses. The change stuck for a while. In January 1962, all multi-orbital Dyna-Soar missions were cancelled. But the next month all military applications Dyna-Soar were removed from the program. DOD Secretary Robert McNamara determined it would make a better research aircraft and announced Dyna-Soar's re-branding it as an orbital research program.
The amendment was formalized in June. Dyna-Soar took on the moniker of X-20 to solidify its research status. A blow to those who hoped to see a weaponized Dyna-Soar fly, McNamara's support did ensure funding through 1964.
In September 1962, a full scale Dyna-Soar mockup and seven pilots - soon to be astronauts - were unveiled to the public in Las Vegas. But the dream didn't last. By early 1963, it was clear that NASA's success was eclipsing Dyna-Soar. The glider just didn't fit anywhere in the nation's Moon shot, and NASA's dominance in space left little room for an Air Force version. A study weighing the merits of Dyna-Soar with NASA's upcoming Gemini program ended with the latter firmly on top. On Dec. 10, 1963, Robert McNamara formally cancelled Dyna-Soar.
Though the full-scale mockup is as close to a flying Dyna-Soar Boeing ever built, the program did have lasting benefits. While the bureaucratic mess dealt the program blow after blow, the pilots did learn how to fly the small delta wing glider to an unpowered landing as though from orbit. They practiced in simulators and unpowered aircraft with equivalent aerodynamic properties. So when it came time for NASA to develop the space shuttle, results from all the Dyna-Soar studies were readily available. The unflown vehicle convinced the agency that unpowered landings from orbit were the best way forward.
Image credit: NASA