John Goodwin Tower was born in Houston on Sept. 29, 1925, the son of a Methodist minister. He joined the Navy in World War II at the age of 17 and served for three years in the Pacific on a landing craft. After the war he graduated from Southwestern University in Georgetown, Tex., and earned a master's degree in political science from Southern Methodist University in Dallas before studying for a year at the London School of Economics.
Mr. Tower taught political science at Midwestern University in Wichita Falls, Tex., served as a Sunday school teacher and worked as an insurance salesman and a radio announcer.
In his 24 years in the United States Senate, John G. Tower, the first Republican Senator from Texas since Reconstruction, became one of the most influential and knowledgeable lawmakers on military and national security issues. But when he left Washington in 1989, he departed in virtual humiliation.
Serving four terms in the Senate, Mr. Tower was chairman of the Armed Services Committee when he retired in 1984. In the 1970's and early 80's he was a leading advocate of modernizing and expanding the military, and served as a central player in Congress in President Ronald Reagan's efforts to build up the nation's military arsenal.
He was survived by two daughters, Penny Tower Cook and Jeane Tower Cox, both of Dallas. A third daughter, Marian, was killed with him in the plane crash which took his life.