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LONDON - Steve Fossett, the millionaire adventurer who went missing in a light plane over a US desert last year, may still be alive, investigators say.
Fossett disappeared last September during a flight over the Nevada desert and, despite a massive search, his body and plane have never been found.
The failure to find any trace of Fossett has sparked speculation he may have faked his own death.
Lieutenant Colonel Cynthia Ryan, of the US Civil Air Patrol, said Fossett could still be alive.
"I've been doing this search and rescue for 14 years. Fossett should have been found," she is quoted as saying by London's Telegraph newspaper.
"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."
Fossett's disappearance prompted the biggest search in American history, with the Civil Air Patrol using infra-red technology, backed up by private planes and internet experts scanning the Nevada desert for clues.
Investigators have questioned Fossett's financial situation, his choice of a light aircraft for the flight, and the fact he left his global positioning system watch at home.
Risk assessor Robert Davis conducted an investigation for insurers Lloyd's of London, which is said to face a £25 million ($67.61 million) payout on Fossett's death.
"I discovered that there is absolutely no proof that Steve Fossett is actually dead," he said.
"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."
Fossett, an aviator, sailor and record-breaking balloonist, was declared legally dead in February.
- AAP