By Thomas Watkins
The Associated Press
SAN CLEMENTE, Calif. — Investigators were trying Friday to determine why a Coast Guard airplane on a nighttime search for a missing boater collided with one of four Marine Corps helicopters flying in formation to deliver troops to a training exercise on a military island off Southern California.
The collision occurred minutes after civilian air traffic controllers told the Coast Guard C-130 pilot to begin communicating with military controllers, said Federal Aviation Administration spokesman Ian Gregor.
All seven people aboard the C-130 and the two-person crew of the Marine Corps AH-1W Super Cobra helicopter remained missing as a search of a 644-square-mile area focused on a debris field about 50 miles off the San Diego coast.
"A tragic event," Pentagon spokesman Bryan Whitman said. "The search is still on, but it's likely taken the lives of nine individuals."
The C-130 crew had survival gear aboard the aircraft, including exposure suits that could have allowed them to survive in the water for hours, Petty Officer Henry Dunphy said.
It was not known whether the pilots of the C-130 and the helicopters were aware of each other before the 7:10 p.m. Thursday collision about 15 miles east of the Navy's San Clemente Island, a heavily used site with training ranges for amphibious, air, surface and undersea warfare.
The Sacramento-based C-130 crew was looking for a man on 12-foot skiff who was reported missing while trying to row from Los Angeles to Santa Catalina Island, said Coast Guard Petty Officer 3rd Class Levi Read.
Drift patterns showed the skiff could be near San Clemente Island, about 25 miles southwest of Catalina.
The AH-1W Super Cobra was flying from Camp Pendleton in northern San Diego County to the island, said Maj. Jay Delarosa, a spokesman for Marine Corps Air Station Miramar in San Diego.
Two Super Cobras, a type of attack helicopter, were escorting two big CH-53E Super Stallion transport helicopters carrying Marines to the island, Delarosa said. He did not know how many Marines were aboard the transports.
After the collision, the other three helicopters returned to base, he said.
The accident occurred airspace uncontrolled by the FAA inside a so-called military warning area, which is at times open to civilian aircraft and at times closed for military use, Gregor said, adding that he did not know the status of the airspace at the time.
Minutes before the collision, the FAA told the C-130 pilot to begin communicating with military controllers at Naval Air Station North Island in San Diego Bay, but it was not known if the pilot did so, Gregor said.
FAA controllers never communicated with the Cobra pilots, Gregor said.
Capt. Tom Farris, commander of the Coast Guard's San Diego sector, said that area where the accident occurred is under Navy control.
Farris said that in that area pilots are responsible for seeing other's aircraft around them.
Pilots "operate in that area on a see-and-avoid principal," he said.
The investigation will involve recordings of transmissions by the aircraft, the FAA and Navy controllers, he said.
The four-engine C-130 was conducting its search from an altitude of 900 to 1,000 feet and visibility was 15 miles, according to the Coast Guard.
Citing the continuing investigation, Delarosa said he couldn't comment on whether the helicopter pilots were aware of the Coast Guard search operation. He said that since it was after dark the helicopter pilots would have been wearing night-vision goggles.
Navy spokeswoman Angelic Dolan declined to answer questions about the collision.
The search for the man on the skiff continued.
The C-130 was based at the Coast Guard's air station in Sacramento.
Coast Guard flotilla Cmdr. Ron Clark said the primary mission of the base's C-130s is search and rescue in an area stretching from the Canadian border to Ecuador and halfway to Hawaii. The station is also responsible for marine enforcement ranging from drug interdiction to fisheries.
Clark declined to discuss the collision, referring calls on that to the San Diego operations.
The offshore military airspace occupies a wide swath of area from the U.S.-Mexico border to California's central coast.
San Clemente Island is the southernmost of the Channel Islands off the Southern California coast.
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Military flights are common along the San Diego County coast. Marine helicopters are often seen flying from coastal Camp Pendleton to ships and the island.