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Stripped but Unchanged

By James T. McKenna | August 1, 2005

A closer look at how Eurocopter's "Mystery Chopper" conquered Everest.

A TEAM OF EUROCOPTER PILOTS, MECHANICS AND engineers stripped about 120 lb. from the AS350 B3 used to set down on the summit of Mount Everest in mid-May, team members say, but made no modifications to alter the aircraft from its basic production configuration.

The team removed extra seats and any other extraneous items that could be unbolted, unscrewed or unstrapped from the aircraft. But nothing was removed that could not be pulled by any AStar operator under normal circumstances. One exception might be the experimental test pilot who achieved what appears to be a world record of 29,035 ft. (8,850 m.) for landing a helicopter.

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The pilot, Didier Delsalle, said he personally shed about 15 lb. in the weeks before resting the skids of his stripped-down aircraft on the peak of the world's tallest mountain. He is a tall, slender fellow, and it is hard to see where he found the pounds to lose. Many another pilot might find it easier to pull the weight from their aircraft than from themselves. An actual exception to the team's production-aircraft standard was the Turbomeca Arriel 2B1 engine. DelSalle did get clearance to exceed the temperature limits for the engine while operating in the thin, high-altitude air between his base camp and the summit,

In other preparations for the flight, DelSalle said, he read everything about Mount Everest and its peak that he could lay his hands on. He said he wanted to get a mental image of what to expect when he approached the summit from the air. "The last thing I wanted was to be surprised." So it was not much of shock for him to find spent oxygen bottles and other debris near the peak.

Eurocopter's quest for Everest was born several years ago, when representatives visiting Nepal to support customers there got a chance to observe the mountain first hand. "I realized it was possible to do it, to land on the peak," one of the fellows said during a break in DelSalle's briefing at the Paris Air Show. The Eurocopter crew's competitive fires were stoked, they said, when they got wind that Bell Helicopter might attempt to set an altitude record near Everest. The thin air there has always been the domain of Eurocopter, its predecessor companies and their Lama helicopters.

A team was assembled that included DelSalle, experimental test engineer Stephane Joulain, experimental test vice president Bernard Fouques, former flight instructor Jean Thomas, and mechanics Joseph Pagano and Jean-Luc Casabianca. They began planning the best way to prep the AS350 B3 and DelSalle for an assault on the summit. (With success in hand, Eurocopter dubbed the aircraft "Mystery Chopper" and painted that name across its top after learning the climbers' groups were chattering about a mystery chopper flying about Everest.

DelSalle began his direct reconnaissance of the mountain on May 5. Working from the base camp at Lukla at an elevation of 9,403 ft. (2,866 m.) on Everest, he got himself familiar with the terrain and the vagaries of the winds and weather around Everest. That environment could be brutal. DelSalle reported that, at one point, he encountered updrafts so severe that his aircraft was climbing at 5,000 fpm. in autorotation. When asked what emergency procedures he had in mind for his approach, DelSalle replied that the only one was to simply to clear the area to the left of the aircraft clear. "If I did that, I knew I could do a 9,800-ft. autorotation" to a safe landing area.

The Nepalese peak of Everest that was DelSalle's objective is just that--a peaked ridge. It is too narrow to permit landing the aircraft entirely. DelSalle could only set his skids on the mountain for the period prescribed by the F餩ration A鲯nautique Internationale, the world's arbiter of aviation records, to qualify as a landing. That requirement is more than 2 min.

On May 12, Delsalle flew from Lukla to the South Pass at roughly 26,000 ft. (7,925 m.) and landed. By the 14th, he was ready for his ascent. He reached the peak and at 0708 local time planted his skids, attempting to keep them in contact with the peak despite winds that approached 50 kt. Video of the flight later showed his skids were on Everest for nearly 4 min. before taking off.

Once he lifted off, DelSalle circled to the left for a 360-deg. view of the summit. He'd realized, he said, that in all his flights there he'd been so focused on the tasks at hand that he hadn't taken in the view. "I needed to see what I'd done."

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