This document has been declared "Stabilized" and will no longer be subjected to periodic reviews for currency. Users are responsible for verifying references and continued suitability or technical requirements. New technology may exist.It is intended that this SAE Aerospace Recommended Practice (ARP) will set down guidelines for the development and test of gas motors to provide a practical and reliable hot gas rotary actuation mechanism. Specific operational and test requirements shall be specified in a detail specification. The areas to be discussed are: Requirements (performance, environment, life, and reliability), design and fabrication, and test considerations.