In the 1960s, American Airlines was looking for a jet smaller than a 747 that could still fly long distances and carry 400 passengers. They approached Lockheed, who was reeling from the loss of some military contracts. Lockheed decided to give it a go, and wound up with a tri-jet configuration that would go by the name Lockheed L-1011 “Tristar”. Only 250 were produced, meaning Lockheed took a major loss on each one. Problems with engine supplier Rolls Royce hampered production. Meanwhile, the very similar Douglas DC-10 was stealing the show…and customers.
Considering production ended a mere 12 years after the aircraft entered service, the airframes are generally pretty low hour examples. Some small upstart airlines use them until they can finance newer, more efficient aircraft. An upstart rocket builder also uses one to launch it’s rocket into orbit.
Orbital Sciences was formed in 1982 to develop satellites and launch systems. One of their launch systems, making its first flight in 1990, is the Pegasus rocket. The Pegasus, unlike most rocket systems, is air launched. It must be carried to about 40,000 feet and dropped.
The air launch concept does two things: it allows for a smaller rocket since the rocket does not have to pass through the densest part of the atmosphere, and it allows for a flexible launch location. Different locations are preferred for different flight profiles. If the satellite is to have a polar orbit then launching further north, such as from Vandenberg AFB in California, is preferred. An equitorial orbit means a launch near the equator is preferred.
Shortly after the debut of the Pegasus rocket, Orbital Sciences modified a former Air Canada L-1011-100 to serve as its air launch craft. The same aircraft also supported NASA’s X-34 and X-43 programs. On board are now engineer stations with various systems for monitoring the aircraft and spacecraft performance.
In a little bit of nerd humor, the L-1011 that Orbital now uses as its launch platform is nicknamed the Stargazer. If you’re a Star Trek TNG fan, you might get the Stargazer-Pegasus connection. Jean-Luc Picard was the captain of a ship called the Stargazer. First Officer William Riker served aboard a ship called Pegasus.
[Image Credits: Public Domain]