SAN DIEGO -- A lost military plane with major historical significance has been found in the waters off San Diego, and an effort is under way to raise it from the ocean floor.

Experts consider the World War II TBD Devastator to be the "Holy Grail" when it comes to restoring naval aircraft.

In the all-important Battle of Midway, the crews of the Navy's torpedo bomber were recognized for their heroism.

It first started flying, but had some vulnerability, experts said.

"It had to fly at a low, slow and straight," said Ed Ellis of the National Naval Aviation Museum in Pensacola, Fla.

While nearly all of the 40-plus planes were shot down in the battle, those air battles allowed other planes to move in and take out Japanese carriers.

Soon after, the Devastator was retired from active service.

Seven decades later, the telling of the plane's history is missing a key element -- the plane itself.

"It's extremely rare; there are none on display in the world," said Ellis.

Ellis said that could soon change because resting in the waters along the San Diego coast is a sunken Devastator.

In 1941, a training flight from North Island ended with a crash landing and a sunken plane.

According to an accident report, the pilot survived, recounting, "A wave hit my left wing. The plane sank right wing first."

A salvage company used sonar to locate the craft and a dive confirmed it was a Devastator.

The company isn't disclosing the location, but according to museum officials, the aircraft is between 3 and 12 miles from shore and under 600 feet of water.

"It's the 'Holy Grail' in terms of naval aviation, and what we'd like to have in this museum," said Ellis.

In August, the museum spearheaded the raising of the World War II Helldiver from Lower Otay Lake.

However, the undertaking for the Devastator will be tougher and more expensive. The museum is searching for sponsors to help with the $300,000 needed to raise the plane.

The museum has kept the Devastator sighting a secret for more than a decade, focusing on a Devastator that sank near Miami. That project is tied up in litigation.

Another Devastator, sunk near the Marshall Islands, would cost more than $2 million to raise, so the San Diego plane has now become the top priority.