McDonnell Douglas seems to have gotten it done, from a quick skim of [1]. It appears they ran out of funding and the program was cancelled. According to the sam

McDonnell Douglas seems to have gotten it done, from a quick skim of [1]. It appears they ran out of funding and the program was cancelled. According to the same article, > Elon Musk stated that the SpaceX Falcon 9 development was "... continuing the great work of the DC-X project." So... [1] https://en.wikipedia.org/wiki/McDonnell_Douglas_DC-X https://en.wikipedia.org/wiki/McDonnell_Douglas_DC-X