ST. AUGUSTINE, Fla. -- Below the waves, down on the ocean's bottom, the underwater world is full of mystery.
It's enough mystery to turn Joe Kistel and his team of divers into detectives.
They're with the TISIRI organization which stands for Think It, Sink It, Reef It.
TISIRI specializes in artificial reefs.
"We've got a lot of reefs offshore in Northeast Florida," Kistel noted.
This summer, Kistel and his fellow divers went to a reef that wasn't on their maps.
There, they found two big tires a wing structure.
They, indeed, found a plane.
"This wasn't placed by any means," Kistel explained.
The plane had crashed there.
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"From our standpoint, this isn't something we're familiar with either," Kistel said. He's used to diving artificial reefs which are purposefully created.
And here's the mystery: they had no idea what plane it was.
"The mystery behind it is very attractive," Kistel said.
Intrigued, they dove the siteoff of St. Augustine again.
"I was rummaging around," the site, Kistel said. Amidst the wreckage, something little caught his eye.
"I broke this little piece off, and I almost discarded it," Kistel recalled. "But I looked at it closely, and it had this piece of sheet metal riveted on it."
For kicks, Kistel brought that chunk of metal to the boat and cleaned it up.
"And we were able to see 'Property of the U.S.,' which is exciting because that narrowed it down to a military aircraft," Kistel said.
It was a lucky clue.
That piece just so happened to have the plane's data plate on it and a number on it.
"That specified this plane as an A-7," Kistel explained.
Not many A-7s have had mishaps, according to the U.S. Navy, but Kistel found out there was a "mishap" 20 miles off the coast of St. Augustine.
"We thought this might be some family member who was lost or didn't come back," Kistel said. "And at best, maybe we can provide some closure for a family."
Kistel researched more with the U.S. Navy.
"I actually found Robert Besal as the pilot's name, and his age at the time of the accident was 24," he said.
A Google search lead Kistel not to a dead pilot's family, but to the the pilot himself!
Bob Besal teaches aviation maintenance and lives with his wife, Jenny, in Charleston, South Carolina.
Besal remembered the first phone call from Kistel this fall.
"I received that phone call in the evening as I was driving home from teaching school," Besal said.
Kistel recalled: "I said, "Bob I think I found your plane."
Besal described that call as "a bolt from the blue."
Joe said Besal got really quiet.
Besal remembered thinking, 'I thought I buried that about 37 years ago.' He now said "I don't exactly cover myself with glory."
Besal is a retired U.S. Navy Admiral now, but in the 1970s he was stationed at Naval Air Station Cecil Field as a new pilot with the A-7 Corsair II.
There's a date and time he'll never forget: December 2nd, 1974, about 10:30 in the morning.
He was above the clouds, above the Atlantic, training.
"I was part of a four plane formation," Besal recalled, "I sort of became disoriented."
Besal's plane aimed right at another aircraft.
He remembers thinking, "Oh my God. This is going to be very close!"
Besal was so close that he could see inside his commander's cockpit. Besal's tailfin collided with the fuselage of his commander's plane.
"And I heard a very loud bang, and the plane shuttered, and then it went out of control."
Besal ejected. He had a parachute.
"I remember seeing an airplane," Besal noted. "I didn't know if it was mine. It was descending to the clouds that were below us."
A short while later, a helicopter eventually plucked Besal from the ocean. His commander's plane made it back to Cecil.
However, Besal never went back to that watery site off St. Augustine.
"There are some things you hope are put to rest," he said.
Besal didn't even tell many people about the crash, until that diver named Joe found that crusty chunk of airplane.
"If you think of all the things that wind up in the ocean," Besal commented, "that they'd come across this and do all that detective work! Well, that's pretty impressive."
Kistel invited Besal to go out with the TISIRI team to the site.
Besal agreed, and nearly 40 years later, he returned to St. Augustine with his wife, bound for a plane he left 20 miles off the coast.
Twenty miles out means you no longer can see the land. Every once in a while you may see another boat, but so much closer is that plane wreckage just 80 feet below.
Besal laughed, "Eighty feet! It's a forever away! 80 feet!"
Once the TISIRI boats hovered over the exact site, the dive gear went on, the dive flag went up, and the divers went down.
Besal doesn't dive, but he sat in awe looking out at this place, sometimes quietly saying "wow!"
"Sometimes I'm at a loss for words," Besal said as he surveyed the ocean's waves.
Down below, the rusty plane sits in piles.
"The structure down there is not really recognizable as a plane," Kistel described the site. "Basically, you've got this material of the jet that has this depth of growth: coral sponges and vertebrates and marine life are all over it. It's a very natural looking reef now. "
Kistel's team brought up a few artifacts for Besal to look at. They were fresh off the plane.
Besal got excited as he began to identify the pieces. Some made him shake his head and laugh.
At one point he held a dripping wet piece and said, "Yeah, yeah, yeah! See that gray piece of vinyl was cockpit stuff!"
It was stuff from his cockpit. It's a reminder that he survived.
And his plane has become a living place too in a way.
It's an artificial reef -- full of life -- by accident.
"It's certainly being used for something other than it was intended," Bob smiled.
It's a sunken place where two men's paths collided this fall.
And from that place, they took away some fish for dinner, some mementos, and an unexpected mystery ... solved.