Seattle helicopter crash: Was broken tail rotor the cause?

Video shows that a news helicopter that went down in Seattle and killed two people this week began rotating at takeoff before it pitched forward in a fiery crash, the National Transportation Safety Board says.

The surveillance footage taken from three security camera recordings near the crash site shows the aircraft began rotating counterclockwise during takeoff Tuesday morning and rose slightly, nearly level, from a rooftop helipad, the agency said late Friday night in a preliminary report.

The helicopter continued rotating counterclockwise for about 360 degrees before it pitched forward, nose low. It "continued the counterclockwise rotation in a nose low attitude until it disappeared from the camera's field of view," the agency said in its one-page statement.

What does that mean? The likely cause of this kind of counterclockwise rotation is the failure of a tail rotor, according to helicopter pilots discussing the NTSB report in online forums.

As The Christian Science Monitor reports, the NTSB is concerned about a rise in helicopter accidents in the US.

The NTSB outlined helicopter safety as a major advocacy priority, citing “an unacceptably high number of helicopter accidents,” in an NTSB Most Wanted List report. Since 2004, more than 1,600 accidents have claimed more than 500 lives.

“The NTSB is concerned that these types of accidents will continue to occur if a concerted effort is not made to improve the safety of helicopter operations,” the NTSB report states.

This year alone, there have been 10 other helicopter crashes in the United States, two of them fatal, according to NTSB data.

The agency called on helicopter operators, manufacturers, and regulatory agencies to revise safety management practices, including inspection and maintenance procedures. Specific recommendations called on operators to ensure that pilots receive adequate training in maneuvering during compromising conditions and to restrict the schedules of maintenance personnel to ensure alertness.

Available video apparently did not show the actual crash on a street next to the Space Needle, where the KOMO-TV chopper burst into flames, setting several vehicles ablaze and spewing burning fuel down the street.

Multiple witnesses reported seeing the helicopter lift off and begin a counterclockwise rotation, then pitch downward, still rotating, and crash. They indicated the fire began after the crash, the NTSB said.

Witnesses earlier told reporters they heard unusual noises coming from the aircraft as it lifted off from the helipad atop KOMO's six-story headquarters after refueling. The initial NTSB report did not discuss any noises.

The helicopter came to rest on its right side and "all major structural components" were located in the immediate area of the main wreckage, the NTSB said. Wreckage debris was found in a 340-foot radius of the main wreckage.

The initial report did not attempt to pinpoint a cause for the crash. A final report could take as long as a year, agency officials have said.

Agency investigators moved the wreckage to a secure hangar in Auburn, south of Seattle, where they are reconstructing the helicopter.

The wreck killed both men on board — pilot Gary Pfitzner, 59, and former KOMO photographer Bill Strothman, 62. The two worked for Helicopters Inc., of Cahokia, Ill., which owned the Eurocopter AS350 aircraft.

The agency continues combing through pilot and maintenance and company records associated with the flight, the NTSB's Dennis Hogenson said earlier. Investigators are focusing on the helicopter's engine, the airframe, the pilot and the environment.

A Seattle man in a car, Richard Newman, 38, was seriously burned when the helicopter crashed and caught fire. Newman underwent surgery Friday and afterward was reported back in intensive care in serious condition, a Harborview Medical Center spokeswoman said. He suffered burns covering nearly 20 percent of his body, on his back and arms.

The agency cautioned that the initial report was preliminary information and subject to change.

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