Thomas R. Holtz, 76, an aerospace engineer who specialized in propulsion systems and worked for the military contractor TRW for 30 years, died Feb. 3 at Capital Caring’s Halquist Memorial Inpatient Center in Arlington County.

He had cardiopulmonary disease, said his son Thomas R. Holtz Jr.

Mr. Holtz retired from TRW in 1992. His projects over the years included assignments for the Energy Research and Development Administration and the Energy Department and NASA initiatives including rocket engines, the Gemini and Apollo programs and the Skylab space station.

Earlier, he worked for the Marquardt Corp., Pratt & Whitney and North American Aviation on jet engines and military planes. From 1997 to 2004, he worked for the Federal Aviation Administration on a rocket project.

Thomas Richard Holtz was born in Wauwatosa, Wis. He received a bachelor’s degree in mechanical engineering and thermodynamics from the University of Wisconsin at Madison in 1958, a master’s degree in astronautics in 1962 from Rensselaer Polytechnic Institute in Troy, N.Y., and a master’s degree in mechanical engineering from the University of Southern California in 1965.

He settled in the Washington area in 1975 and was a Great Falls resident. His memberships included St. Catherine of Siena Catholic Church in Great Falls and the Veterans of Foreign Wars auxiliary.

Survivors include his wife of 54 years, Constance Miller Holtz of Great Falls; four children, Marie Kolls of Fairfax County, Thomas R. Holtz Jr. of Upper Marlboro, Michael Holtz of Arlington County and Father Dominic Holtz, a Catholic priest, of Rome; three sisters; two brothers; and three grandchildren.

— Emily Langer