Taiwan's accident investigators believe that fuses from runway lights broken by the crash of a Singapore Airlines Boeing 747-400 at Taipei will resolve the issue of whether or not the closed runway 05R was lit at the time of the accident.
Flight SQ006 crashed in bad weather at night on 31 October while attempting to take off from 05R, which was cluttered with construction machinery.
The death toll in the crash has now risen to 83 of the 159 passengers and 20 crew on board.
It has been confirmed that the green centreline lights on 05L were lit at the time of the crash, which is entirely normal for a taxiway.
Although tower controllers at Taipei's Chiang Kai Shek International Airport claim that its edge lights were switched off, surviving cabin crew have insisted that they were on. The runway's edge and threshold lights are controlled by a single switch.
According to Kay Yong, chief investigator and managing director of the Taiwanese Aviation Safety Council (ASC), "unbiased results" showing whether the runway edge lights were on or off are expected by mid-December.
"We have found two fuses which were broken by the crash. We are planning to conduct non-destructive tests to see whether those fuses were under current or not under current when they were struck," he adds.
Yong says that at the time of the crash there were no markings - large yellow crosses painted on the runway surface - to show runway 05R was closed. "There was no closed runway sign marked, but there is now."
He says that a group of investigators has been formed to look into "the safety of the airport itself", and will assess whether procedural issues could have contributed to the SIA captain's decision to turn onto 05R instead of continuing along taxiway N1 to 05L as cleared.
The two parallel runways are separated by 200m (650ft).
Source: Flight International