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Robert Truax (1917-2010) was one of the great originals of American rocketry and a major proponent and inventor of ultra-low-cost rocket engine and vehicle concepts. A longtime member of the American Rocket Society (serving as its president in 1957,) He received the Robert H. Goddard award for outstanding work in liquid propellant rockets as well as the Legion of Merit citation for his conceptual work on making the "Polaris" guided-missile submarine a primary naval weapon. Truax was also inducted into the Air Force Space and Missile Pioneers Hall of Fame in 2003. Inspired by Robert Goddard, Truax began building rockets when he was a teenager in California. From 1936 to 1939, while enrolled at the United States Naval Academy, he tested liquid-fueled rocket motors. During the late 1940s, he organized the US Naval Missile Test Center's propulsion laboratory at Point Mugu, California, and headed rocket development within the Navy's Bureau of Aeronotics where he advanced the concept of a staged combustion system upon which the Space Shuttle's main engines would eventually rely. In 1946, Truax led a team that interrogated the rocket engineer for Nazi Germany, Wernher von Braun. By 1955, however, his proposal for a submarine-launched ballistic missile had failed to win Navy approval and he joined the Air Force's newly established Western Development Division (WDD) From 1955 to 1958, Captain Truax headed the Thor intermediate-range ballistic missile (IRBM) development program. Truax studied the sea launching of rockets, such as the Sea Bee and Sea Horse projects. In 1959 he retired as a Captain, and headed the Aerojet-General Advanced Development Division and Aerojet's Sea Dragon project in the Advanced Development Division until leaving in 1967. In 1966 Robert Truax founded Truax Engineering Inc. (TEI,) which studied sea launch concepts similar to the earlier Sea Dragon—the Excalibur, the SEALAR (Sea Launched Rocket,) and the Excalibur S. Here his low-cost booster program plan was elaborated and further studied, but he was again unable to interest NASA or the USAF in the concept of cheap access to space. In the 70's and early 80's, Truax, heretofore prominent in scientific communities, emerged in popular culture. Literally building rockets from his own backyard in Saratoga, Truax built both of Evel Knievel's "Skycycles" for his 1974 for attempt to jump the Snake River Canyon. He later competed in the original X-prize competition to send a private astronaut into suborbital flight. Robert Truax, died on September 17 aged 93, as a key figure in the rocket research that took America into the space age, while also being an inspiration to the do-it-yourself, back-yard amateur.



Processing Information

The processing archivist kept original file unit titles when possible. Titles written by the archivist appear in brackets.


Truax, Robert Collins, 1917-2010



bulk 1980-2000


Truax Estate, gift, 2016


12.95 Linear feet (21 Legal Size Boxes, 1 Slim Legal Size, 3 Shoe Boxes, 1 Flat Box)


Robert Truax was one of the great originals of American rocketry and a major proponent and inventor of ultra-low-cost rocket engine and vehicle concepts.


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Collection descriptions

Archival materials

Arrangement note

This collection was arranged into series by the processing archivist. There was no original order when the collection was received. Series 1: Personal & Business Papers Series 2: Papers Authored by R.C. Truax Series 3: Drawings Series 4: Images 4:1 - Slides 4:2 - Photos, Negatives & Floppy Discs

Scope and Contents

This collection consists of material relating to the career of Robert Collins Truax including correspondence, photographic material, technical drawings, technical manuals and reports, presentation and conference materials, papers by Truax, news clippings, published materials and business records for Truax Engineering, Inc. Projects and programs referenced in this collection include the Knievel Rocket Car (Truax X-2 Sky-Cycle); X-3 Volksrocket; amphibious launchers, including the "Sea Dragon," "Sea Horse," and SEALAR (Sea Launched Rocket); the Space Shuttle program; the Gemini and Apollo programs; Rocketdyne LR89 Liquid-Fuel Motors; Rand Project; the Corona Reconnaissance Satellite; and Project Private Enterprise. The researcher should note that the collection also contains audio-visual material. These items are not included in the finding aid but the NASM audio-visual archivist can assist you regarding access.


Permissions Requests

Topics Truax X-3 Volksrocket
SEALAR (Sea Launched Rocket)
Manned space flight
Space Shuttle Program (U.S.)
Kneival Rocket Car (Truax X-2 Sky-Cycle)
North American Aviation, Inc. Rocketdyne Division


Robert C. Truax Collection, Acc. 2016-0008, National Air and Space Museum, Smithsonian Institution.

Archival Repository

National Air and Space Museum Archives

Finding Aid Online Finding Aid