Team tries to resolve sunken-jet mystery

The 46-year-old underwater mystery beckons to John Gisselbrecht.

Where's the body of reservist U.S. Marine Capt. John Eaheart?

And where's his F-9F Cougar jet fighter?

Both are thought to be at the bottom of southern Flathead Lake.

Gisselbrecht and a pair of Idaho underwater search specialists hope to find both in an up-to-two-week search expected to begin this weekend.

Gene and Sandy Ralston of Boise brought a sophisticated side-scanning sonar to Whitefish Lake two weeks ago to locate the body of a drowned Canadian man. The Ralstons specialize in finding underwater bodies and other objects.

Their presence caught the attention of Gisselbrecht, 45, of Kalispell, a contract air crewman who dives on the side to explore underwater plane and ship wrecks. He saw that the Ralstons' equipment might be able to find the pilot and wreckage of a Cougar fighter that crashed into Flathead Lake in March 1960.

The Ralstons agreed to help hunt for Eaheart's body, Gisselbrecht said.

Eaheart, a former University of Montana basketball player, was a Western Airlines pilot who was engaged to a flight attendant in the same company.

In 1960, he went to Alameda Naval Air Station in California for his two weeks of annual Marine reservist training. As part of the training, he flew his F-9F, an update of a Korean War fighter that saw some action in the early Vietnam War, to Malmstrom Air Force Base in Great Falls.

At the time, his fiancee was at her parents' house in the Yellow Bay area.

One evening, Eaheart left Malmstrom and flew over the Yellow Bay house a couple times at an altitude of 2,000 feet. He then flew over Flathead Lake again, turned south over Wild Horse Island, and then turned again to the east over the Big Arm area.

Witnesses at that time reported a flash or explosion from the plane. The jet dived into the lake with a second explosive sound erupting when it hit the water. But no oil or fire spread across the surface from the second explosion.

Parts of the plane - but not the main 42-foot-long fuselage - were recovered. Eaheart's helmet was found floating a day after the crash, but the pilot's body was never found.

Gisselbrecht said he always has been fascinated by underwater wrecks and explores them as a hobby.

"When you get down there, it triggers a response in you: 'Why is it there?' … It's like looking at a puzzle," Gisselbrecht said.

Checking witness reports and other information, Gisselbrecht theorizes that the downed fighter is roughly 270 feet beneath the lake's surface within a 1/4-mile-by-1/4-mile square along a line between Blue Bay and Matterhorn Point.

Gisselbrecht talked with Eaheart's former fiancee in 1994, but has since forgotten her name. He is also looking for witnesses from 1960 and hopes they will call him at 755-2238.

He is being helped in the effort by the Museum of Mountain Flying in Missoula, where he does some volunteer work. The Marine Corps League and the Veterans of Foreign Wars are interested in placing a memorial plaque on the shore after the plane is discovered, he said.

If the side-scan sonar and other remote-control underwater detection equipment don't work in May, the searchers will likely regroup and try deepwater diving later in the summer. Normal divers have a depth limit of 130 feet; going deeper requires special equipment and training.

If the body or plane are found, they will be examined for clues to the crash. However, there are no plans to recover the body or the plane, Gisselbrecht said. Instead, the shoreline memorial will be set up.

Reporter John Stang may be reached at 758-4429 or by e-mail at jstang@dailyinterlake.com.