HELIOS 522 MANUAL
One can conclude from the report that its possible the pilots assumed the cabin pressure system was in the proper place (auto) when in fact it was set to manual (MAN) and subsequently were confused by the alarm or thought it was faulty. Generally speaking "Don Oxygen Masks" is the first item on the emergency checklist following the mishap of the South Dakota LearJet crash in 1999. Many might say they did in fact know there was a problem but for some unknown reason they did nothing about it. Of the warnings ( Cabin Altitude Warning Horn, Passenger Oxygen Masks Non-identification of the warnings and the reasons for the activation The crew would have been alerted by alarms to the depressurization event This is the one of the debated/interesting aspects of the accident.
Unaware of this and didn't realize the extent of the problem. Helios Flight 522 crashed when the crew unknowingly suffered hypoxia.Īlthough the masks in the passenger cabin deployed, the crew were I will pull some excerpts from that below.
HELIOS 522 FULL
You always have to remember: In high altitudes you become unconscious after less than 30 secs without the mask, and as the masks can only produce a limited amount of oxygen it's a really time critical issue to reach the flight-deck and initiate a descend if the pilots are already out of service!įirst and foremost you should read the accident report which you can find in full here. In my opinion the cabin crew should be trained to know what's normal procedure if masks drop, but I would definitely tell a flight attendant about my concerns if nothing happens after two minutes or so. Either the pilots already suffered hypoxia or they didn't notice the passenger masks drop at all.
If neither of those options happens something is definitely wrong. In both cases I would expect an announcement that the oxygen masks are not needed and can be put down safely. If this doesn't happen it would be possible that the crew deployed the masks manually for no reason or the automatism faulty detected a low cabin pressure. In this special situation, as you know that the oxygen masks deploy automatically if the cabin altitude raises to high, you expect the aircraft to descend in order to allow the pax to breathe normally again. Investigations said the passengers were alive but unconscious at the time of the crash, though some Greek officials believe many passengers froze to death during the flight.It's never bad to inform a crew member about anything you think may be abnormal. The plane was out of gas and it crashed into a mountain outside of Athens. The 737’s pilots were slumped over their controls and passengers were wearing oxygen masks.Ī moment of hope emerged when a flight attendant, still conscious after using several crew oxygen containers, made his way into the cockpit and took the plane’s controls. Unresponsive to radio communication, the jet flew into Greek airspace, where two F-16s intercepted it. Even after oxygen masks dropped to passengers, the plane continued its climb. Instead, pressure started dropping 13 minutes into the Cyprus-to-Prague flight.Īlarms sounded onboard but the pilots, beginning to feel the effects of hypoxia, misinterpreted them. Investigations after the crash showed that the flight crew had several opportunities to notice and correct the setting, but they never did. The system was never switched back to auto. The problem with this 737 began when ground crew set the plane’s pressurization system to manual to check a reported leak. Human error was the root of this terrifying 2005 ghost flight that crashed outside of Athens and killed all 121 people onboard. A Cypriot airplane belonging to Helios Airways plowed into a hill north of Athens on 14 August 2005, killing all 121 people onboard in the worst airline disaster in Greek history.