HL-42 (spacecraft)

HL-42

NASA schematic from Access to Space Study
Operator	NASA
Applications	Crewed spaceplane
Specifications
Launch mass	29 tonnes, including adapters
Regime	Low Earth orbit
Production
Status	Cancelled
Launched	0
Related spacecraft
Derived from	HL-20 Personnel Launch System

The HL-42 was a proposed scaled-up version of the HL-20 re-usable crewed spaceplane design, which had been developed from 1983 to 1991 at NASA's Langley Research Center but never flown. Like the HL-20 ("Horizontal Lander 20"), the HL-42 would have been launched into low Earth orbit mounted on top of a two-stage expendable rocket. At the end of the mission, it would have re-entered and glided to a runway landing.

The HL-42 was suggested as one possible successor to the Space Shuttle in the 1994 NASA Access to Space Study. However, another alternative, a Single-stage-to-orbit design, was chosen for further development, and work on the HL-42 was abandoned.