Round the world flying adventurer Steve Fossett may have faked his own death due to personal problems or fears about his business dealings, according to investigators.
Fossett, the first man to fly non-stop round the earth in a hot air balloon, went missing last September when his final flight in a light plane over the Nevada desert went missing.
His disappearance sparked the biggest search in American history, with the Civil Air Patrol's Black Hawks, fitted with infra-red technology, joined by over 30 private planes and internet experts scanning the Nevada desert looking for clues.
However, Lieutenant Colonel Cynthia Ryan of the US Civil Air Patrol has said Fossett, whose body or plane was never found, could still be alive.
"I've been doing this search and rescue for 14 years. Fossett should have been found," the Telegraph quoted her, as saying.
"It's not like we didn't have our eyes open. We found six other planes while we were looking for him. We're pretty good at what we do," she added.
Lt Col Ryan believes that the friend of Virgin tycoon Richard Branson may have faked his own death following revelations of his personal life.
There are also a number of anomalies that question whether Fossett's plane ever crashed.
A pilot at hotel magnate Barron Hilton's flying ranch near Reno, claims to have seen him take off that day.
According to the pilot, Fossett asked him to prepare the plane for take off, even though he had never allowed anyone else to do this before.
Fossett also apparently claimed he was going to scout for locations for a land speed record attempt, but he supposedly took off with no emergency equipment.
The choice of plane was also a baffling one - a Bellanca Citabria Super Decathlon, which, according to risk assessor Robert Davis said was constructed from a steel and wood frame, but actually covered in fabric, making it easy to dismantle.
Davis conducted an eight-month investigation for insurers Lloyd's of London, said to face a 25 million pounds payout on Fossett's death.
"What I've strived to find out is what happened to this man in the run-up to his disappearance, why did he disappear? he said.
"I spoke to reporters who were on the scene, people who were helping out with the search efforts, anyone whom I thought could shed some light on this.
"I discovered that there is absolutely no proof that Steve Fossett is actually dead. I'm not a conspiracy theorist, I'm a man who deals in facts, and I don't really care if he is alive or dead, it make no difference to me.
"What I am interested in is the truth - and a proper criminal investigation of this man's disappearance was never undertaken by law enforcement or officials in the state of Nevada," he added.