Orion is a series of

American American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, pe ...

solid-fuel rocket A solid-propellant rocket or solid rocket is a rocket with a rocket engine that uses solid propellants ( fuel/oxidizer). The earliest rockets were solid-fuel rockets powered by gunpowder; they were used in warfare by the Arabs, Chinese, Persian ...

stages, developed and manufactured by a joint venture between

Hercules Aerospace Hercules, Inc. was a chemical and munitions manufacturing company based in Wilmington, Delaware, United States, incorporated in 1912 as the Hercules Powder Company following the breakup of the DuPont explosives monopoly by the U.S. Circuit Co ...

and

Alliant Techsystems Alliant Techsystems Inc. (ATK) was an American aerospace, defense, and sporting goods company with its headquarters in Arlington County, Virginia, in the United States. The company operated in 22 states, Puerto Rico, and other countries. ATK's ...

(now

Northrop Grumman Innovation Systems Northrop Grumman Innovation Systems (NGIS) was a sector (business segment) of Northrop Grumman from 2018 through 2019. It was formed from Orbital ATK Inc. a company which resulted from the merger of Orbital Sciences Corporation and parts of Alli ...

). They were originally developed for use as all three stages on the

Pegasus rocket Pegasus is an Air launch to orbit, air-launched launch vehicle developed by Orbital Sciences Corporation (OSC) and now built and launched by Northrop Grumman. Capable of carrying small payloads of up to into low Earth orbit, Pegasus first fl ...

, first flown in 1990. Orion is available in several configurations for a variety of use scenarios. All stages in this family are fueled by a mixture called QDL-1, which includes

HTPB Hydroxyl-terminated polybutadiene (HTPB) is an oligomer of butadiene terminated at each end with a hydroxyl functional group. It reacts with isocyanates to form polyurethane polymers. HTPB is a translucent liquid with a color similar to wax paper a ...

and 19%

aluminium Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...

, with the exception of the yet-unflown Orion 32, which uses QDL-2, containing HTPB and 20% aluminium.

Versions

Orion stages are numbered to indicate their configuration. The first number, either 38 or 50, indicates the diameter of the stage. This is followed by various letters. S indicates a stretched, first stage variant. XL indicates an additional stretch. G indicates a ground-launched stage, with a shorter nozzle. T indicates a strengthened skirt.

References

{{Rocket engines Alliant Techsystems Spaceflight Solid-fuel rockets