Why was such an awesome rocket cancelled? How is NASA trying to reduce costs when they invested billions in SpaceX and Boeing and United Launch Alliance (ULA) but did not continue investing millions in the Delta Clipper?
The cancellation of the Delta Clipper project ultimately was about about NASA politics rather than technological value, but even so, it probably wouldn't have been a great launcher.
According to Wikipedia:
NASA had taken on the project grudgingly after having been "shamed" by its very public success under the direction of the SDIO. Its continued success was cause for considerable political in-fighting within NASA due to it competing with their "home grown" Lockheed Martin X-33/VentureStar project.
First, note that the 60 million dollar development was not for Delta Clipper itself, but for DC-X, which was a scaled down technology demonstrator.
DC-X was tiny and carried no payload, and could not get anywhere near orbit; its liftoff mass was about 19 tons.
The proposed DC-1 orbital Delta Clipper would have a liftoff mass of around 470 tons, and take 4.5 tons to LEO. That's a 1% payload fraction; 2%-3% is more typical for two-stage launchers.
Astronautix has the DC-1 launch price estimate at \$350 million 1991 dollars (\$660M 2020 dollars), which seems very steep; I don't know if they're accounting for reusability there.
Even if Delta Clipper's reusability had cut launch costs dramatically, it still wouldn't be competitive with two-stage-to-orbit expendables and partially-expendables -- single-stage-to-orbit rockets just can't carry much payload.
The DC-X was not built by NASA but by the DOD. After the DOD was done with it, it was transferred to NASA.
"Built as a one-third-size scale prototype, the DC-X was never designed to achieve orbital altitudes or velocity, but instead to demonstrate the concept of vertical take off and landing."
The DC-X achieved its goals. When it was destroyed in an accident, there was no compelling reason to rebuild it.
The DC-X was small, at 4 meters diameter, with a payload capacity of only 3000 lbs. \$60 million only bought the concept prototype. To build the necessary preproduction and production models could have brought the total costs into the billions. Still not out of the question if the rocket was capable, and that was a large problem, it was not. As a single stage sub orbital rocket with small payload it was never envisioned to be comparable to the shuttle or falcon 9. Small payload, low ceiling equals limited utility.
To date no single stage rocket has ever reached orbit. Huge research dollars to achieve a single stage orbital rocket were cost prohibitive in the Bush Sr. era when the US defense department budget would be cut 10% in 4 consecutive years. Then cut again under early Clinton. (The Cold War was over).
NASA was holding out for a more traditional more capable rocket like the Aries V or SLV.
How is NASA trying to reduce costs when they invested billions in SpaceX and Boeing and ULA but did not continue investing millions in Clipper?
As for NASA “wasting” money on SpaceX, I would say when the Space Launch Vehicle finally launches it will cost over \$2 billion per launch with no re-use, added to the \$19 billion development cost. Added to the \$230 billion cost of its failed predecessor the Constellation program which failed to deliver its Ares V rocket (predecessors of the SLV) before being canceled in 2010. The \$60 million per launch of the falcon 9, developed with private money, is a bargain. When the new larger Starship comes online, also developed with mostly private money, its launch cost is projected to be only \$2 million (SpaceX costs) for more than 4 times the payload of the Falcon 9. Any money NASA spends with SpaceX in my book is a bargain.