How a “Single Switch” Killed 121 Passengers in the Helios Flight 522

In 2005, the Helios Airways Flight 522 crashed near Grammatiko, Greece, killing all 121 passengers and crew on board, making it the deadliest aviation accident in Greek history.
The investigation into the crash found that the most likely cause of this tragic incident was a maintenance error. In order to perform a pressurization leak check, the pressurization system was set to "manual." However, the engineer failed to switch it back to "auto" upon completion of the test. Before takeoff, no one on the crew noticed this incorrect setting.
As Helios Flight 522 climbed, the cabin pressure dropped and a warning horn sounded, but the crew mistakenly identified it as a takeoff configuration warning. Despite several other warning lights illuminating, including the passenger oxygen light, the crew did not realize the seriousness of the situation.
Within minutes, the crew and passengers began to lose consciousness. The captain and co-pilot were the first to succumb to hypoxia. The aircraft then crashed into a mountainside, and there were no survivors.

[Roc_ky]

That's not a maintenance issue it's a pilot issue not doing complete checks properly.

[iaexo]

Which is why now in the 737NG preflight checklist (standard Boeing) it asks for PRESSURISATION MODE SELECTOR - AUTO

[Shadow_king]

Even if the Flight Attendant would land the 737 safely, everyone would be in irreversible comas.
Flight 522 was doomed from the start

[rodmeers]

When were the pilots going to realize the seriousness of it after it crashed

[VanyPZ]

For Those Who Dont Know:

Helios Airways Flight 522 Was A Flight That Crashed Near Greece Killing 121 People Due To The Maintenance Crew Forgetting To Set The Cabin Pressurization To Automatic Making All People Fall Unconscious And Apparently Someone Walked Into The Cabin Signaled To The Fighter Jets By Waving Trying Their Best To Land The Plane, But Failed So The Plane Crashed Into Hills In Greece Not Even Past 3 Hours After Takeoff - This Took 3 Seconds To Type I Dont Expect Credit.

[dr.bright]

Sounds like there was a witness against Boeing on that flight!

[DarkMatterOfficialYT]

The flight attendant that sacrificed himself to crash the plane 🕊🕊🕊

[Wubbabunga]

Im pretty sure there was one passenger who didn’t succumb to the loss of cabin pressure and tried to land the plane himself with the help of the Air Force? But he failed.. :(

[LunandKun]

A guy survived when they were dead when the plane was flying he controlled the aircraft but it crashed killing him and everyone onboard

[planes]

Actually there was a flight attendent tried to fly the plane but he crashed it and he also survived

[Ruby-vmce]

Noone saw that ? Dont they have a checklist ? Why the hell they get relatively good money monthly ...the pilots should ve checked that

[jknKkKiJjNnN]

Why do people even fly 😂, wouldnt trust anyone w my life tho

[KristGaming]

Actually not everyone was unalived only some died and the families whose members were unalived were gave money.

And who ever survived were just unconscious.

Hope this helps.

[matthewjohnston]

Definitely should have an auto override once you get above a certain altitude.