Six people died when a business jet trying to take off in Maine crashed in a snowstorm

PORTLAND, Maine — Six people died when a business jet crashed during takeoff as a snowstorm moved in and visibility diminished in Maine Sunday night.

The Bombardier Challenger 600 flipped over and burned on takeoff at Bangor International Airport around 7:45 p.m. Sunday night as the nation's massive winter storm was beginning to reach the area.

An audio recording of air traffic controllers posted by www.LiveATC.net includes someone saying ''Aircraft upside down. We have a passenger aircraft upside down,'' about 45 seconds after a plane was cleared for takeoff. First responders arrived less than a minute later, airport director Jose Saavedra said.

Experts say the weather and questions about whether ice accumulating on the wings kept the plane from getting airborne — as has happened at least twice before on that plane model — will likely be an initial focus by the National Transportation Safety Board. However, the agency will consider all possible factors.

''You can count on the fact that NTSB is going to look very closely at this,'' said John Cox, who is CEO of Safety Operating Systems.

The airport said Monday afternoon there were six people aboard, according to the flight manifest, and all died. Earlier in the day, the Federal Aviation Administration had said seven died and one was injured but warned the numbers were subject to change, and the agency defers to local authorities.

Snowfall was heavy elsewhere at the time of the crash, but accumulation had just started in Bangor. Other planes had been taking off safely. But about half an hour before the crash, the pilot of a Florida-bound Allegiant plane radioed the tower to abort his takeoff.

At about the same time, the pilot of the Bombardier had taxied over to the deicing pad and was radioing in a request to get his plane's wings and tail treated, according to audio posted by www.LiveATC.net. The plane remained at the deicing pad for about 20 minutes before taxiing to the runway.

History of icing problems with these planes

The Bombardier Challenger 600 model ''has a history of problems with icing on takeoff'' that caused previous deadly crashes in Birmingham, England; and Montrose, Colorado, more than 20 years ago, aviation safety consultant Jeff Guzzetti said. Even a little bit of ice on the wings can cause serious problems, so careful inspections and de-icing are a crucial step before takeoff, the former federal crash investigator said. And there is a time limit on how long de-icing remains effective. It could last only about 20 minutes.

The National Weather Service in Caribou, Maine, said the airport eventually received nearly 10 inches of snow, but it was just beginning to fall at the time of the crash. Wind speeds were about 10 mph, which is not out of the ordinary. Temperatures dropped below 3 degrees (minus 16 Celsius) while the jet was in Bangor.

Cox said those conditions wouldn't keep planes from flying.

''Given the weather conditions at the time, and the history of wind contamination with this particular aircraft, I'm sure that's something the NTSB is going to look into immediately,'' Guzzetti said. ''If there was any kind of precipitation at all, freezing precipitation, they would have needed to clean off those wings before they took off.''

The Bombardier Challenger 600 is a wide-bodied business jet configured for nine to 11 passengers. It was launched in 1980 as the first private jet with a ''walk-about cabin'' and remains a popular charter option, according to aircharterservice.com.

Crash investigators in England recommended improved procedures for ice detection after a 2002 crash, but significant changes weren't made until after the NTSB finished its investigation in 2006 of the Colorado crash that killed the son of NBC television executive Richard Ebersol.

The FAA published new rules afterward to make clear to pilots and airports that even a small amount of frost on the wings can be a problem. The agency also clarified the standards for de-icing to make certain that all frozen particles are removed from the wings, and it required a combination of tactile and visual inspections.

Bombardier was also required to add a cold weather operations warning to the plane's flight manual after three incidents in Canada where one of these planes rolled unexpectedly in ways the pilot didn't command during take offs in cold weather and icing conditions.

The crash victims have not been officially identified

The identities of those onboard won't be released publicly until they can be confirmed, officials said.

The jet was registered to a corporation that shares the same address in Houston as the personal injury law firm Arnold and Itkin Trial Lawyers, and one of the law firm's founding partners is listed as the registered agent for the company that owns the plane.

The international airport in Bangor, about 200 miles (320 kilometers) north of Boston, is one of the closest in the U.S. to Europe and is often used to refuel private jets flying overseas. The Bombardier was headed for France when it crashed.

The airport shut down after the crash and will remain closed at least until Wednesday so the FAA and National Transportation Safety Board investigators can examine and remove the wreckage.

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