As the stricken plane went down, four parachutes were spotted and military rescue teams retrieved the crew members, said Lt. Chris Sims, a Navy spokesman in Washington, D.C.
The crew members, whose conditions are unknown, were being taken to Balboa Naval Hospital, according to Sims.
The plane plummeted to the ocean about 30 miles west of the location where a Coast Guard boat was releasing the grey whale JJ into the ocean after a year in captivity. The aircraft was unrelated to the whale release, which took place as planned.
The plane was an S-3B Viking, a $27 million, twin-engine jet built by Lockheed Martin. It performs anti-surface missions and carrier-based refueling.
The plane, attached to Squadron 41, was on a training mission. The squadron, based at North Island Naval Air Station, trains crews for the S-3.
The Coast Guard initially sent a cutter and helicopter, but the Navy had "plenty of assets in the area, so we held back," Coast Guard Petty Officer Kevin St. Pierre said.
The location of the downed aircraft was 35 miles west of Point Loma, about half-way between Point Loma and San Clemente Island, St. Pierre said.
The San Diego coast is a major training ground for the Navy. Among Navy ships in the area is the aircraft carrier USS Abraham Lincoln, preparing for deployment to the Western Pacific, Indian Ocean, and Arabian Gulf.
©1998, CBS Worldwide Inc., All Rights Reserved. The Associated Press contributed to this report