NTSB: Medical helicopter crash is 9th this year

(CNN) -- The midair collision of two medical helicopters in Arizona that killed six people Sunday is part of a "disturbing" national tendency, a National Transportation Safety Board official said Monday.

"This has been a serious issue. Just this year there have been eight of these incidents," NTSB Chairman Mark Rosenker said in a news conference in Arizona. "We want to see if there are issues that we need to fix to prevent these midairs [collisions] from happening."

Rosenker had left out the Arizona collision in his figures. Sunday's incident is the ninth collision or crash involving medical helicopters -- killing 16 this year, according to the NTSB. In 2007, there were 14 such crashes.

Not all of the eight crashes that Rosenker cited occurred in flight, but he said the NTSB is concerned about the number of collisions and crashes of medical aircraft and is studying the safety issue.

"We are concerned about that," he said. "That is why we are going to work very, very hard to understand what happened here."

The only survivor, an emergency nurse, was in critical condition, Flagstaff police Sgt. Tom Boughner said.

Rosenker told reporters the collision was recorded by a motion-sensitive camera atop a parking deck at the hospital. It has been sent to a lab in Washington for enhancement, because a time-date stamp is blocking the view of the collision.

He said NTSB investigators, who arrived at the scene Monday, would begin examining the wreckage Tuesday. They will also seek training records, dispatch communications, 72 hours of the pilots' flight history and employee histories.

Toxicology tests were conducted on the two pilots, Rosenker said.

He said both helicopters were trying to land at the Flagstaff Medical Center -- one was approaching southbound, the other northbound.

"They were both in a place they should've been in a normal operation," Rosenker said. "The question is, why didn't they see each other?" Watch as victims are carried from the crash site »

He said the weather was clear and sunny at the time of the collision.

FAA spokesman Ian Gregor said three of those killed were aboard a Bell 407 helicopter operated by Air Methods Corp., an air medical service provider.

Rosenker said the pilot aboard the Air Methods helicopter dropped off an individual earlier to meet weight requirements for landing at the hospital.

Three others were killed aboard the other helicopter, a Bell 407 operated by Classic Helicopter Service of Utah. The surviving nurse was on that helicopter.

Killed in the collision were the two pilots, two medics and two patients, said Flagstaff police Sgt. Tom Boughner.

The helicopters set fire to a 10-acre area after crashing to earth, according to fire officials, and three rescue workers were injured by a secondary explosion after the crash.

Concerns over emergency medical helicopters prompted an investigation into such operations detailed in a January 2006 NTSB report. The report noted that emergency medical operations are unique in their inherent danger because of the high-pressure circumstances to which they respond, unfamiliar landing sites and around-the-clock emergencies, often in inclement weather.

That investigation identified several safety issues involving emergency medical flights, including:

-- Less stringent requirement for emergency medical operations conducted without patients on board;

-- A lack of aviation flight risk-evaluation programs;

-- A lack of consistent, comprehensive flight dispatch procedures;

-- No requirements to use technologies such as terrain awareness and warning systems to enhance flight safety.

The report made recommendations addressing the issues to the FAA.

FAA spokeswoman Alison Duquette told CNN on Monday that while the number of fatalities dropped between 2006 and 2007, the agency now is seeing an increase.

She said the FAA is working on making some of the NTSB's 2006 recommendation into regulations.

"There is a lot of interest in the issue," she said. "We've had quite a few accidents recently. ... It's part of a larger issue. These are a unique type of operations -- they have an emergency nature to their mission."

In recent years, the FAA has issued notices to emergency helicopter pilots regarding risk management training and better training for flying at night and in inclement weather.

But it's unclear weather such measures would have prevented Sunday's deadly collision.

"Most accidents involve making decisions to go in marginal or bad weather, which has nothing to do with the recent accident," she said.

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