THE Taipei airport runway on which a Singapore Airlines jumbo jet crashed on take-off last October did not have a sign saying it was closed, an investigator into the disaster said on Feb 23.

And the runway which the plane should have used did not have a "runway guard light", which indicates it is active during low visibility.

Nor was there a sign guiding pilots to enter the runway at the time of the crash -- at night and during lashing typhoon rain.

Kay Yong, managing director of Taiwan's Aviation Safety Council, highlighted the age of Chiang Kai-shek airport as he released a 400-page report summarising the investigation of the crash which killed 83 of 179 people on board.

The plane ploughed into construction equipment on the closed runway 05 right when it should have used runway 05 left.

Yong said some facilities at the airport fell short of international standards, but neither he nor the report drew any conclusions.

"There are some areas that did not meet international standards," Yong told a news conference in reference to the lighting and signs. "It is an old airport built in 1979."

He noted that the pilot of flight SQ006 had decided to take off even though the plane's para-visual display (PVD) was not on but he stopped short of blaming the airport facilities or the pilot's judgment call.

He declined to say whether the PVD, which helps pilots determine whether a plane is on the runway centreline in poor visibility, was supposed to be on.

The Los Angeles-bound jet exploded in a fireball after hitting the construction equipment parked on 05 right in the first fatal incident in the airline's 28-year history.

Singapore Airlines accepted full responsibility for the crash of the Boeing 747-400 but also called for a review of facilities at the airport.

"When we accepted responsibility for the SQ006 accident, we said that we wanted to understand how and why such a tragic accident could have happened," the airline said in a statement issued in Singapore.

"This report...sets out the facts. As we understand it, the next phase of the investigation will analyse these facts to determine how and why this accident happened. We will await the final analysis before commenting further."

In a preliminary report issued last December, the investigators ruled out problems with the plane.

Feb 23's report said Foong Chee Kong, 41, the Malaysian pilot, and first officers Ng Kheng Leng, 38, and Latif Cyrano, 36, both Singaporeans, were all convinced they were on runway 05 left.

In the report, it said one of the first officers told the investigators he "was prepared to tell the pilot not to take off if the runway picture was not right".

But the report did not say why the first officer failed to do so or whether it would have mattered.

A final report from the investigators is expected later this year.

Taiwan prosecutors conducting a separate investigation into the October 31 crash restricted the pilot and the two first officers from leaving Taiwan until December 21 as they debated whether to press criminal charges.

Taiwan's decision to release the three followed intense pressure from the Singapore government and condemnation by the Singapore media and the London-based International Federation of Airline Pilots' Associations, which threatened to boycott Taiwan.

The investigators include representatives from the United States National Transportation Safety Board and the Singapore government.