Helios crash investigation results due February

THE long-awaited probe on the causes of the August 14 airline disaster should be ready by February next year, chief investigator Akrivos Tsolakis said yesterday.

Speaking on Greek TV network NET, Tsolakis said the clues to the puzzle were beginning to fall into place, after months of painstaking evidence-gathering.

“This has to be the most complex crash in Greek history,” Tsolakis said on a live news show.
He added that all relevant data from the plane’s black box had been retrieved.

Helios flight 522 struck a mountain cliff before disintegrating over a sprawling ravine at Grammatikos, near Marathon. All 121 passengers and crew onboard were killed.

The information so far points to human error. It is believed that before the doomed flight, maintenance crew who had conducted a pressurisation check left the control in manual instead of automatic, so the aircraft did not pressurise as it gained altitude. But the crew failed to notice the setting in their pre-take-off checks, and the post-take-off checks require no further confirmation of the pressurisation control selection.

When the audible cabin altitude alert sounded, the crew thought it was an erroneous configuration warning because the sound is identical. According to Tsolakis, the pilots’ “subsequent mindset and actions were determined by this preconception until hypoxia overcame them as the aircraft continued to climb.”

The gradual loss of oxygen rendered both the crew and passengers unconscious.
Earlier, Tsolakis had said he had received reports from numerous other national aviation authorities advising him of events similar to the Helios one, but with “non-fatal outcomes.”
Yesterday he revealed that the re-enactment of the horrific crash would take place on 20 December, another sign that investigators were getting closer to the truth.