Gordon H. McCormick Sr., a retired Navy captain and aeronautical engineer who later became a real estate appraiser for Howard Brock Realty Co. in Northern Virginia, died July 15 at his home in Fairfax County. He was 89.

The cause was pneumonia and congestive heart failure, said his daughter Maureen McCormick.

Capt. McCormick enlisted in the Navy in 1943. He commanded an amphibious boat group during World War II and later worked as a Navy representative to aircraft-engine manufacturer Pratt and Whitney. From 1969 until his military retirement in 1974, he developed, designed and tested aircraft at the Naval Air Systems Command. He then worked as a real estate appraiser for Howard Brock for about a decade.

Gordon Hugh McCormick was born in Wilmington, Del., and was a 1940 graduate of Western High School in Washington. He received a bachelor’s degree in aeronautical engineering from Catholic University in 1943 and received a master’s degree in industrial engineering from Purdue University in West Lafayette, Ind., in 1954. He did postgraduate work in engineering at the Naval Postgraduate School in Monterey, Calif., and received a master’s degree in business administration from George Washington University in 1976.

He was a member of St. Leo the Great Catholic Church in Fairfax City and the Knights of Columbus. He volunteered with Mended Hearts, a volunteer organization that offers counseling to heart patients.

His wife of 53 years, Ruth Schoenfeldt McCormick, died in 2005.

Survivors include four children, Paul McCormick of Newton, Ga., Ann Newman and Maureen McCormick, both of Fairfax, and Gordon McCormick Jr. of Carmel, Calif.; and a sister.

— Megan McDonough