Hudson air corridor among most challenging in US

[August 11, 2009]  WASHINGTON (AP) -- Small-plane and helicopter pilots traverse the Grand Canyon, skirt the rims of Hawaiian volcanos, and soar along crowded urban skyways that are sometimes literally under the radar, relying mostly on their eyes to guide them. Nowhere is that more challenging than in the narrow air corridor over the Hudson River.

Nine people -- two men and a boy from a Pennsylvania family in a single-engine Piper, and five Italian tourists and a pilot in a tour helicopter -- died last weekend in a collision in the congested flyway, which is popular with sightseers.

Aviation experts said other places around the country share some of the difficulties inherent in the Hudson corridor, which stretches 12 miles from the George Washington Bridge past the Statue of Liberty and is sandwiched between the river's New Jersey and New York shores. However, they said, nowhere else has as much traffic and as great a variety of aircraft in such a narrow confine.

"There is no getting around it that the New York airspace is one of the busiest airspaces in the world," said Matt Zuccaro, president of the Helicopter Association International in Washington, which represents helicopter operators, manufacturers and pilots.

New York Police Department divers found the wreckage of the small plane and one of two missing victims on Monday, but the man's body couldn't be removed from the wreckage. Police suspended their diving operations Monday evening and were to return to the water Tuesday.

The Federal Aviation Administration has divided the airspace around 30 of the nation's busiest airports into layers, with airspace above 1,100 feet restricted primarily to commercial airliners and other large planes. Below that are defined corridors where small planes, helicopters and other general aviation aircraft are permitted to fly.

Some of the busiest corridors are in Los Angeles, Chicago, Boston and Dallas. A key difference is that those corridors aren't as narrow as the corridor where the accident took place Saturday, nor are they lined with tall buildings on both sides, creating a kind of aviation canyon. The corridor that follows Chicago's Lake Michigan shore, for example, has tall buildings on just one side.

Air traffic controllers aren't responsible for separating aircraft in the corridors to keep them from colliding -- that's up to the pilots to do themselves, using what they call "see and avoid," which comes down to watching out their windshields for other aircraft heading in their direction.

Two other areas of the country that share some similarities with the Hudson corridor are the Grand Canyon and Hawaii's volcanoes, where accidents involving helicopter tours have been the focus of high-profile investigations by the National Transportation Safety Board.

Accidents at the canyon have declined sharply since the FAA limited helicopter tours primarily to flying around the rims and over the top, rather than down inside, but traffic remains heavy and is not supervised by controllers.

"It's still a risky environment," said former NTSB member John Goglia.

There have been calls from New York officials and others to limit air traffic in the Hudson corridor in the wake of the accident.

"It seems to me that the 'see and avoid' rule isn't working in the New York airspace and you are going to have to go to either requirements for additional technology or some additional restrictions to fly in the airspace," said former NTSB Chairman Jim Hall.

That worries some of those who use the corridor.

"I'm concerned about inappropriate knee-jerk reactions without the facts," Zuccaro said. "What I support is a professional review of the accident by those best trained in area -- let the NTSB and the FAA do their job."

[Associated Press; By JOAN LOWY]

Associated Press writers Tom Hays in New York and Victor Epstein in Hoboken, N.J., contributed to this report.

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