Below 1, 100 feet, well-defined corridors exist for small planes and helicopters to fly without needing permission from air-traffic control.

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At another local hospital, Memorial Medical Center, a small fleet of helicopters was brought in to evacuate patients and staff after hospital officials were told "by officials on the ground to take the matter into our own hands, " said Trevor Fetter, president of Tenet HealthCare Corp.

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The number of helicopters in Asia represents only a small percent of the number of helicopters in the United States, while Asia has a significantly larger population and is expected to be a major market for helicopters over the next two decades.

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But the helicopters and small aircraft from neighbouring Tajikistan and Pakistan that at once started to arrive in Faizabad, carrying medical and other relief supplies to be flown to outlying villages, were soon desperately overstretched.

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When the president travels, especially overseas, it's a flying circus with 800-1, 000 people, limousines, helicopters, communications equipment, big guns, small guns, sometimes food, and often 20-30 planes.

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