A New Hampshire couple that was seriously injured in a fatal helicopter crash on Kaua'i this year is suing the aircraft's owner and parts manufacturers, citing faulty design and substandard materials, according to a lawsuit filed in O'ahu circuit court yesterday.

Judy L. Barton, 51, of Newport, N.H., suffered a spinal injury in the March 11 crash and is paralyzed from the waist down. Her husband, Douglas W. Barton, 60, suffered a broken arm in the crash.

Passenger Michael Gershon, 60, of Walnut Creek, Calif., was killed in the crash of Inter-Island Helicopters' Hughes 500. Another passenger, Dania Hansen, 60, of Los Altos, Calif., suffered serious injuries.

The helicopter was built by McDonnell Douglas Helicopter Systems in 1987 and was owned by Smoky Mountain Helicopters Inc., doing business as Inter-Island Helicopters, according to FAA records.

It previously had been used by the Ventura County Sheriff's Department in California, according to FAA records.

The suit, filed by L. Richard Fried Jr., names the Boeing Co., Aluminum Precision Products Inc. and Smoky Mountain Helicopters. Boeing merged with McDonnell Douglas in 1997.

The suit seeks unspecified damages.

Fried could not be reached yesterday for comment.

Messages left with Boeing, Smoky Mountain Helicopters and Aluminum Precision Products were not immediately returned yesterday.

On March 11, the helicopter's tail section blew apart in flight, and witnesses saw at least two pieces fall to the ocean.

The Inter-Island Helicopters aircraft, also designated as a McDonnell Douglas 369, with a pilot and four passengers, crashed into the grass at the YMCA's Camp Naue, killing Gershon.

Passengers and witnesses reported hearing one or two loud bangs before the crash. At the crash scene, the entire tail rotor section was missing.

Pilot Donald Torres told the National Transportation Safety Board that he had inspected the tail rotor section more than once that day without noting anything out of order. Among the inspection results were "no signs of cracks, dings, or delaminating of the surface and leading edges of the tail rotor blades," all nuts were properly seated and no visible cracks in any of the parts of the tail rotor assembly were found.

The helicopter was being flown with the doors off, as is customary.

Torres said that after he heard a noise, the helicopter turned to the right and failed to respond to the control pedals. He said he realized that his tail rotor, which helps control the direction of the helicopter's body under the turning main rotor, had somehow failed.

Torres saw the lawn of the YMCA camp and directed the spinning helicopter toward it. He managed to reach the edge of it, but struck a large false kamani tree and landed on a fence, which shattered from the impact.

The helicopter ended up on its side.

The initial inspection of the remaining portion of the tail rotor gearbox at the NTSB's Materials Laboratory found overstress fractures in remaining metal parts. But no cause for the stress that destroyed the rotor section has been identified.

Reach Peter Boylan at pboylan@honoluluadvertiser.com.

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