Recoverable Rocket Boosters by Tony R. Landis, AFMC History Office
Irwin Stambler gives some information on this Lockheed ten-passenger cargo carrier in Orbiting Stations. As described, the vehicle would launch initially from a hot-water-propulsion rocket sled. Two nested fly-back boosters take the payload stage to orbit. I put the image scanned from the book on Flickr, it’s a hair wider than AFMC’s version and shows the artist’s signature. So, not so much a mystery as it is a spacecraft without a name. More here on Aerospace Projects Review, and more again here on Secret Projects.
Image credit: Lockheed
Image source: AFMC