Survivors of a fatal Jandakot plane crash have joined forces with the victims' widows to sue engineers, owners and maintenance companies involved in making and maintaining the plane.
The multi-million-dollar lawsuit, due to go to trial in the Supreme Court in August, will come six years after the August 11, 2003, tragedy, when the twin-engine Cessna crashed into bush and burst into flames soon after take-off.
Malcolm Cifuentes, Michael Knubley and Ozan Perincek were badly injured in the crash that killed 38-year-old engineer Harry Protoolis.
Steven Warriner, 40, had burns to 90 per cent of his body and died 12 weeks later.
The five men, who worked for Fremantle company Nautronix, were being flown by pilot Alex Penberthy on the chartered plane to Rottnest Island.
Mr Cifuentes, who spent three weeks in a coma after the crash, had severe burns to his face, chest, lower back, forearms and hands.
Mr Knubley and Mr Perincek also had severe burns to various parts of their bodies.
Mr Protoolis' widow, Janet Graham, and Mr Warriner's widow, Julie, have joined the men, and company Nautronix, in the Supreme Court action that will decide the liability issues involved in the crash.
The group is claiming various levels of damages and compensation from Aeronautical Engineers Australia, its engineer Aaron Barclay, Fugro Spacial Solutions, which owned and operated the plane, Kevron Aviation, which maintained the aircraft, and Samotite Aviation Services, which made a sleeve bearing for the plane.
The Civil Aviation Safety Authority is also listed as a defendant in the case, while Mr Penberthy is suing, and being sued, as part of the multi-party action.
The various plaintiffs have commenced legal proceedings gradually since 2006 but have come together in the past 12 months for the legal action.
It is understood that damages may be assessed by the District Court, depending on the outcome of the trial.
During a hearing last week, Supreme Court Justice Anthony Templeman ordered a lawyer for one of the defendants to fly from Melbourne to appear before him on Wednesday to explain why there had been a delay in getting information to the various parties.
At a 2006 coronial inquest into the deaths, State Coroner Alastair Hope found the failure of a fuel pump part made from the wrong alloy caused the plane's right engine to stop shortly after take-off.
The plane hit trees and burst into flames.
The part had been approved for use in the fuel pump by Mr Barclay, whom CASA had authorised without interviewing.
Mr Hope found CASA's supervision and auditing of its authorised officers fell short of specified targets.