Click on the multimedia link below for pictures of Steve Fossett

WHEN Stuart Radnofsky first encountered Steve Fossett at the Le Mans 24-hour endurance race in 1993, the record-setting American sportsman was standing at the back of a garage in his racing suit, reading a biography of Albert Einstein.

“You don’t meet many drivers like that,” said Radnofsky, a former Formula One marketing consultant who went on to become a close friend and business partner in Fossett’s latest quest for competitive glory – an attack on the world land speed record of 763mph, set in 1997 by Andy Green, the British driver.

Like many of Fossett’s friends and colleagues, Radnofsky was both stunned and mystified by his disappearance last week over western Nevada. He had taken off in near-perfect weather for a sightseeing flight in a light aircraft he had flown before.

On Friday, Radnofsky put a brave face on the increasingly gloomy prospects for his friend’s survival. But his voice repeatedly cracked with emotion as he described Fossett as “an extraordinary individual with a great capacity for endurance and a great mental rigour for dealing with bad situations”.

As the hunt for the aviator entered its sixth day yesterday, his situation could not have been much worse. After a difficult start to the search effort amid high winds and severe turbulence above the Nevada desert, conditions improved on Wednesday. Rescuers were then able to check more than half of a search area that expanded to 17,500 square miles of mountain terrain that resembles the more remote battlefields of Afghanistan.

Yet despite at least four credible sightings of Fossett’s plane soon after he took off at around 9am last Monday, officials admitted they were no closer to establishing what route the adventurer had flown or where his aircraft may have gone down. There are now doubts that he was wearing a Breitling watch equipped with a personal emergency transmitter.

A Nevada air force reserve C-130 transport plane with sophisticated electronic listening equipment scoured the area for traces of the watch and a locator beacon attached to Fossett’s plane. But “it did not pick up any signal whatsoever”, said Major Cynthia Ryan of the Nevada Civil Air Patrol (CAP).

Bumping along in a Cessna light aircraft at 3,000ft above the jagged ridges that sprawl across the desert 300 miles east of San Francisco, it was easy to see why the searchers were having such difficulty. Forbidding peaks and empty valleys stretched to the southern horizon. This is one of the most barren corners of America, a rugged wilderness that has swallowed at least 150 light aircraft crashes in the past five decades.

Scarred by deep ravines that never see sunlight, it is also home to some of America’s fiercest thermal currents. The town of Minden, 60 miles from the ranch where Fossett was staying, bills itself as “the world’s greatest soaring site” for gliders.

Yet according to local pilots, the winds that are so friendly to gliders can be deadly for heavier aircraft. As our Cessna crossed a low ridge, it bucked and jolted uncomfortably as it hit a new current of air. If a light aircraft is travelling too close to the ground, a sudden down-draught can slam it against a mountain.

“Down-draughts are not good for us,” explained Lee Elson, a retired Nasa scientist who now gives flying lessons out of Minden’s tiny airport.

Elson happened to be flying on Monday at the same time as Fossett, 63, a multi-millionaire former commodities trader who teamed up with Sir Richard Branson for a series of hot air balloon and aircraft adventures.

“The conditions were pretty benign,” Elson said as he steered our Cessna towards calmer air over a valley. “But there was some wind and where there’s wind there’s turbulence, and where there’s turbulence there’s a chance of getting into trouble if you fly too close to the ground.”

Elson said he saw an aircraft like Fossett’s single-engine Citabria Super Decathlon flying close to the summit of Mount Patterson, an 11,500ft peak close to the Nevada-California border. “As we went around the mountain we could see him for a little while, then we didn’t see him any more. I didn’t think about it until I heard the news reports about Fossett on Tuesday.”

He reported the sighting to the CAP, which has focused its search on a broad swathe of desert and mountain to the south and east of the 1m-acre Flying M ranch, where Fossett spent last weekend as a guest of Barron Hilton, the 79-year-old hotel magnate and aviation buff.

Early reports said Fossett had gone flying in search of dry lake beds as possible sites for the high-speed testing of his jet-propelled land speed challenger, Spirit of America. But Radnofsky and other associates said the “Target 800 (mph)” team had already checked possible sites and settled on options elsewhere.

Radnofsky, who lives in Britain, spoke to Fossett shortly before he left his Colorado home for the Hilton ranch last weekend, and the two men discussed the test runs they had scheduled for later this month on the Bonneville salt flats in Utah. “We think Steve, a bit atypically, decided on a sightseeing flight before leaving the ranch,” said Radnofsky.

With its long private airstrip and its remote yet blissful riverside location in an oasis of greenery surrounded by mountains, the Flying M has long been known as a paradise for aviators. Hilton has turned one wing of the ranch house into his personal retreat; the public areas and cabins scattered around the property have become a kind of invitation-only resort for young pilots who catch Hilton’s eye.

Across the dirt track that provides the only overland access to the ranch is the hangar known to visitors as “Mr Hilton’s toy store”. A passionate aircraft collector, Paris Hilton’s grandfather has acquired a 1941 Stearman biplane, a 1943 Beech Stagger-wing, a McDonnell Douglas helicopter, at least three hot air balloons and his own Cessna Citation executive jet – all at the disposal of his guests.

It was the aerobatic Citabria that Fossett chose for what may prove to have been his last flight. His friends insist he would have had no interest in throwing the plane around the sky – he had always been more focused on feats of endurance, as many of his most remarkable sailing, gliding and flying records attest.

“He was not a fast runner at school, but he just had the greatest stamina,” said Radnofsky. “That’s how he ran across Death Valley, swam the English Channel and skied across the Rockies from Aspen to Vail.”

If Fossett survived the crash, he would need every ounce of that fabled endurance. Although searchers remained resolutely optimistic yesterday, several admitted privately that the chances that he had been able to manage a controlled landing are remote. The most likely scenarios are that he had a heart attack or lost control of his plane when flying too low to recover.

Searchers were buoyed on Friday by news from Oregon that a 76-year-old woman had been found alive after more than a week lost in a mountain wilderness. But local pilots recalled a search for a missing light aircraft in Nevada in 2004. The search was called off after a month and the passengers and wreckage have never been found.080907

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