A faulty engine part led to a fatal Big Island tour helicopter crash that killed the pilot, a tourist couple and their teenage daughter in 2003, according to the National Transportation Safety Board.
The engine part, called the compressor coupling adapter, has been blamed for nine cases of engine failure, according to the NTSB.
The Federal Aviation Administration issued three special warnings about the problem in 2004, and then issued directives in 2005 requiring the part be removed from aircraft engines.
The NTSB report, issued Tuesday, blames the engine part failure for the crash that killed pilot Russell L. "Hoss" Holliday, 35; passengers Jody Laughman, 37, and her 13-year-old daughter, Nicole, and Jody Laughman's husband, James A. Thomas.
Holliday lived in Hawaii, while the other three were from Lake Meade in Adams County in south-central Pennsylvania.
The Tropical Tour Helicopters McDonnell Douglas 369D went down in a lava field nearly halfway into a 45-minute tour flight over the Puu Oo vent in Hawaii Volcanoes National Park. There were no survivors.
An autopsy found that the four victims died in the fire that followed the crash landing.
The families of the victims filed lawsuits against engine manufacturer Rolls-Royce and a company called Extex Ltd.
The suit, which was settled for an undisclosed amount late last year before it went to trial, alleged Rolls-Royce had redesigned the compressor coupling adapter in a way that made it prone to failure, and claimed Extex manufactures the flawed part.
The part is similar to a large nut that links together two sections of the drive train, and when that part failed, the drive train tore apart, said Terry O'Reilly, a San Mateo, Calif., attorney who specializes in helicopter crash litigation and represented Holliday's family.