While at Boeing, he wrote the test documentation for the Minuteman intercontinental ballistic thermonuclear missile. He was also responsible for Boeing's initial testing, which utilized three separate and dynamic environments at the same time. He remained with Boeing through 1959. After working with Boeing, Grose joined the staff of Litton Industries in Woodland Hills, California, where he served as the Director of Reliability and Program Manager of Project SPARR, an Air Force program designed to address general and applied research problems related to space systems. He was responsible for overseeing an applied research space systems risk management program on behalf of the United States Air Force. Grose joined the staff of Northrop Ventura in Rancho El Conejo, California, in 1962, serving as the Director of Applied Technology. In this role, he was responsible for test activities for the engineering department. He participated in the Mercury, Gemini, and Apollo projects of the National Aeronautics Space Administration (NASA), overseeing the chemistry, metallurgy, reliability, configuration management, and value engineering of the program. In 1964, he transferred to Rocketdyne, which was a division of Rockwell International. At Rocketdyne, located in Van Nuys, Grose was named the Chief of Reliability, where he continued to focus on North American aviation, specifically participating in the development of the Gemini and Apollo space programs. Grose has provided keynote addresses and lectured in academic, government, and religious settings for over 50 years. In 1967, he was named the Vice President of Tustin Institute of Technology (now known as Technical Training, Inc.), located in Santa Barbara, California. He was responsible for the development of management curricula and system technology studies. While serving as Vice President of the school through 1981, Grose provided training for management of eight NASA field centers, including Kennedy Space Center, Marshall Space Flight Center, Ames Research Center, Dryden Flight Research Center at Edwards Air Force Base, Lewis Research Center, Langley Research Center, Goddard Space Flight Center, and the Lyndon B. Johnson Space Center in Houston, Texas. He has served as a member of the faculty, adjunct professor, and guest lecturer at universities throughout the world, including Germany, China, Spain, and the US. He served as an adjunct professor with USC in Los Angeles from 1967–1969. He taught Physics and Chemistry of Aircraft & Missile Propulsion at the University of Southern California (USC) Graduate School at Ramstein Air Base in Germany, in 1967. He then taught Space Technology and Management of Research, Development, Test & Evaluation from 1968 to 1969, at Torrejón Air Base in Madrid and Morón Air Base in Seville, Spain, again on behalf of USC's Graduate School.