Space History Photo: HL-20 at Langley
The HL-20 was one of two concepts considered for the Personnel Launch System.
Credit: NASA | Carole Petrachenko Chapman

In this historical photo from the U.S. space agency, the NASA Langley Research Center lifting body, called the HL-20, is shown in front of the hangar.

The HL-20 was one of two concepts considered by NASA as a type of Personnel Launch System (PLS). In essence, it would serve as a space taxi to and from the space station. The full scale engineering model is 29.5 feet long, and 23.5 feet across the wingspan.

Each weekday, SPACE.com looks back at the history of spaceflight through photos (archive).