Lockheed Martin X-33
The Lockheed Martin X-33 was a proposed uncrewed, sub-scale technology demonstrator suborbital spaceplane that was developed for a period in the 1990s. The X-33 was a technology demonstrator for the VentureStar orbital spaceplane, which was planned to be a next-generation, commercially operated reusable launch vehicle. The X-33 would flight-test a range of technologies that NASA believed it needed for single-stage-to-orbit reusable launch vehicles (SSTO RLVs), such as metallic thermal protection systems, composite cryogenic fuel tanks for liquid hydrogen, the aerospike engine, autonomous (uncrewed) flight control, rapid flight turn-around times through streamlined operations, and its lifting body aerodynamics.
Artist's rendition of the X-33 in orbit. | |
| Function | Uncrewed re-usable spaceplane technology demonstrator |
|---|---|
| Manufacturer | Lockheed Martin |
| Country of origin | United States |
| Project cost | $922 million NASA + $357 million Lockheed Martin |
| Size | |
| Height | 20 m (66 ft) |
| Mass | 129,000 kg (285,000 lb) |
| Stages | 1 |
| Launch history | |
| Status | Canceled |
| Engine details | |
| Powered by | 2 XRS-2200 linear aerospikes |
| Maximum thrust | 1,800 kN (410,000 lbf) |
| Propellant | LOX/LH2 |
Failures of its 21-meter wingspan and multi-lobed, composite-material fuel tank during pressure testing ultimately led to the withdrawal of federal support for the program in early 2001. Lockheed Martin has conducted unrelated testing, and has had a single success after a string of failures as recently as 2009 using a 2-meter scale model.