Saturday afternoon, a small propeller plane piloted by a Pennsylvania businessman and a helicopter hired by a group of Italian tourists crashed into each other in the crowded airspace over the Hudson River.
All nine people aboard the two aircraft are believed to have been killed. Divers have recovered five bodies from the river as of Sunday afternoon.
The area is not unsafe, pilots say. But it can be "a very tricky environment," pilot Dan Rose told the New York Daily News. "Almost every time you go down there, you come closer to other planes than you normally do."
The site of the crash is governed by visual flight rules. This means that pilots are flying below 1,000 feet and do not talk to aircraft control towers or file flight plans.
Instead, they essentially police themselves. They are encouraged to report their whereabouts frequently on a radio channel that other pilots can listen to – and to keep their heads on a swivel.
The air corridor is like New Jersey's congested Garden State Parkway, said Patrick Lott, a pilot with the New Jersey Civil Air Patrol, during an interview on Philadelphia radio station WKYW. If you're not paying attention, things can go very wrong, he said.
This is called "see and avoid." But talking is also crucial. Using the special radio frequency, pilots can use well-known landmarks to let other pilots know where they are.
"You might say ... 'I'm at the Statue of Liberty heading northbound.' By listening in, you get a sense of where everyone else is and you can look out for the traffic," Commercial Airline Pilot Ian Dutton told NY1 news channel.
It is too early to assign blame in Saturday's accident, the National Transportation Safety Board (NTSB) says. Eyewitness accounts and videos of the crash should help investigators piece together what happened, though.
What is known is that Steven Altman's Piper Saratoga left Teterboro Airport in New Jersey with his brother and nephew. The helicopter operated by Liberty Helicopter Sightseeing Tours took off from the 30th Street helipad in Manhattan carrying five Italian tourists and the pilot.
It is not yet known if there was any radio communication by either of the pilots. A pilot on the ground, seeing the two aircraft converging, tried to radio a message to both of the pilots but was unsuccessful, the NTSB said.
The NTSB has sought to tighten the guidelines governing for-hire aircraft operators since 2002, but the Federal Aviation Administration (FAA) – which oversees such ventures – has so far not implemented any reforms. Less than a month ago, the Department of Transportation's inspector general said the FAA set a significantly lower bar for safety for the so-called "on demand" industry than it did for commercial airlines.
As an example, the inspector general's report noted that an operator who drops skiers on a glacier several times a day has 17 planes and was inspected eight times by FAA in 2008. A commercial airline with seven fewer planes was inspected 199 times.
Speaking generally, the flight instructor said problems in these sorts of flying zones are more often caused by "weekend warriors" who are not as familiar with the area and not as professional.
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