The search by federal investigators to learn what caused Tuesday's deadly float plane crash near Valdez has taken an unexpected turn. The plane is missing.

"Our understanding is this airplane is obviously still in the water. Unfortunately, it's become unmoored from where it originally started from," said the National Transportation Safety Board's Clint Johnson.

He believes the wreckage is still floating somewhere in Cascade Bay.

"All we know is a couple of passer-bys reported the airplane is no longer tied up on shoreline before, and it had drifted into the bay, and it was kind of at the mercy of the tides and the winds at the time," Johnson said.

It's the latest setback for investigators as they try to solve the crash.

Alaska State Troopers said 56-year-old Scott Johannes of Wasilla, tried to land in the bay when it crashed and flipped. Johannes and an unidentified passenger survived, and escaped the wreckage. Troopers said 75-year-old William Resinger of Palmer remained trapped and died.

The Coast Guard said crews from the boats Vixen and Thin Blue Line, pulled everyone from the water before they transferred them to a Coast Guard ship.

Locals said they are not surprised by the actions taken by the good samaritans

"We all generally do that down here, look out for others when they're in trouble," said Jeffrey Gibson, a boat owner in Valdez.

Tuesday's crash is the third deadly one in Alaska in about a week. The others were near Ketchikan and Metlakatla. With the number of ongoing investigations, local NTSB officials brought up an investigator from Los Angeles to handle the Valdez case.

"He did have a chance to talk to the pilot, the pilot has been very, very forthcoming, very willing to help in any way," said Johnson. "But, we are not drawing any conclusions at this point, we want to look at the wreckage, and confirm a couple of things before we say anything else."

First, though, the NTSB has to once again find the wreckage of the float plane.

NTSB has recorded plane crashes in Alaska in 1962, the agency's accident database shows there have been three fatal crashes in Valdez.

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