All previous crewed spacecraft had been capsules that parachuted back to earth. However, after dropping out of orbit, the shuttle was to fly as a 100-tonne glider towards a landing on a conventional runway. The descent would be steep, and pilots would have only one chance to put the craft down safely. Although NASA considered fitting the shuttle with retractable jet engines, the agency’s experience with lifting bodies—wingless aircraft with a similarly steep rate of descent when flown as gliders—suggested that the weight of engines could be saved and that a steep glide was a perfectly feasible way to get the orbiter back on the ground. In 1977, NASA set out to prove this with the prototype shuttle, Enterprise in a series of approach and landing tests (ALT) at the Dryden Flight Research Center at Edwards Air Force Base in the Californian desert.1
The first of five flights took place on 12 August 1977. A few items from the press kit issued by NASA for the day set the scene.
This first item is a portrait of the crew assigned to the mission: Fred Haise (commander) and Gordon Fullerton (pilot). This is a standard 8″ × 10″ colour lithograph printed on card with a description on the back:
The second item is a pamphlet that describes the ALT program in general, together with an overview of the Space Shuttle system and the orbiter Enterprise in particular.
As described, the plan for the ALT program was as follows:
- Load the Enterprise on the back of a specially modified Boeing 747.2
- Carry it to an altitude of around 25,000 ft (7,600 metres).
- Release it from the 747.
- Pilot it back to earth. The shuttle would drop those 25,000 feet in a little over five minutes—around twice the rate of descent of a typical commercial jet flight.
And finally, the schedule for the day for NASA guests staying at the Holiday Inn at Palmdale: on the bus at 5:30 AM to head out to Edwards Air Force Base; show over and heading back to Palmdale by 9:00 AM.
If you want to see the flight yourself, a video is available on YouTube. Enterprise separates from the carrier aircraft at around the 4′ 30″ mark, and touches down at around the 9′ 30″ mark.
Footnotes:
1 Prior to these tests, NASA conducted a series of flights with the shuttle mounted to its Boeing 747 carrier aircraft, initially without crew and without the shuttle’s systems powered up. Later flights had a crew aboard the shuttle and its systems active. NASA also made a series of flights with an F-104 Starfighter in close proximity to the 747 to explore the ability of the shuttle to separate cleanly from the carrier aircraft.
2 NASA had purchased its Boeing 747 from American Airlines in 1974 to use for aerodynamic research. In 1976, it returned this aircraft (registration N905NA) to Boeing for refurbishment as a carrier aircraft for the space shuttle.
Copyright information: all materials in this press kit were produced by NASA. As works of the US federal government, all are in the public domain.
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