Navy Lt. Cmdr. Gerald (Gary) Neal Seaeff, 43, of Reston, died Aug. 31 on the island of Diego Gargia in the Indian Ocean, where he had been on assignment since Aug. 6. He had suffered a heart attack while playing racquetball.

Cmdr. Seneff served two tours of duty during the Vietnam war as a fighter pilot aboard the aircraft carriers USS Enterprise and USS Coral Sea. He had also served at a number of bases in this country. He had been assigned to the Department of Security Assistance at the Pentagon before leaving for Diego Garcia.

A native of Odon, Ind., he attended Indiana University and Kansas State University. He graduated from the Naval Academy at Annapolis in 1961.

He earned a master's degree in business administration from the Navy's postgraduate school at Monterey, Calif., and a master's degree in international relations from the War College at Newport, R.I.

Survivors include his wife, Anita Smith Seneff, a son, Steven, and three daughters, Sabra, Tamra, and Tanya, all of the home in Reston; a brother Smiley Howard Seneff, of Indianapolis; and three sisters, Marcile Bray, of Los Altos Hills, Calif., Maureen Greene, of Sarasota, Fla., and Leoma Flynn, of Odon.