Helios Flight 522: How a Single Switch Killed 121 Passengers

Summary

Helios Airways Flight 522, on August 14, 2005, became a tragic tale of miscommunication and oversight. The flight from Cyprus to Prague via Athens devolved into a silent disaster when the crew failed to recognize a pressurization issue, leading to hypoxia. Despite alarms and warnings, the pilots did not don oxygen masks, leading to impaired judgment. The flight eventually crashed near Grammatico village, claiming all 121 lives on board. Investigations revealed organizational failures and a flawed alarm system, resulting in legal battles and convictions.

Takeaways

• 🛫 Helios Airways Flight 522, a Boeing 737, was scheduled to fly from Cyprus to Prague via Athens on August 14, 2005, but ended in a tragic accident.
• 🔍 The flight crew reported a strange banging noise from one of the plane's doors during an earlier flight, which was inspected but not properly resolved.
• 🛠 The pressurization mode selector was mistakenly left on manual after ground inspection, leading to a lack of cabin pressurization during the flight.
• 👨‍🔧 Alan Irwin, a UK engineer, was in charge of the inspection and failed to recognize the pressurization mode selector was not reset to auto.
• 👨‍✈️ Captain Hans Jürgen Merton and First Officer Pampos Harolambos had a combined 23,000 hours of flying experience but overlooked the pressurization issue during their pre-flight checklist.
• 🚨 The pilots misinterpreted a critical pressurization alarm as a less severe takeoff configuration warning, failing to take appropriate action.
• 😵‍💫 Both pilots suffered from hypoxia due to the lack of oxygen in the cabin, leading to impaired judgment and inability to address the situation.
• 🛩️ Two F-16 fighter jets were dispatched to investigate the unresponsive aircraft, revealing the pilots were unconscious and passengers motionless.
• 🆘 Flight attendant Andreas Prodromo, a qualified pilot but without Boeing 737 training, attempted to control the plane during its descent.
• 💥 Flight 522 crashed into hilly terrain near Grammatico village, resulting in the loss of all 121 lives on board due to the rapid descent and impact.
• 📋 The air accident investigation report cited multiple failures in recognizing the pressurization issues and criticized an ineffective organizational culture.

Q & A

What was the scheduled route of Helios Airways Flight 522 on August 14, 2005?

The flight was scheduled to travel from Cyprus to Prague via Athens.

Why did the Greek army send two F-16 fighter jets to investigate Helios Airways Flight 522?

The Greek army sent the jets to investigate because there had been no communication from the plane for over an hour and the pilots were nowhere to be seen.

What was the initial issue reported by the crew on the night of August 13, 2005?

The crew reported a loud banging noise coming from one of the plane's doors and noticed that the seal around the door was frozen.

Who was in charge of the inspection of the plane after the crew reported the door issue?

44-year-old Alan Irwin, a well-liked and hands-on engineer from the UK, was in charge of the inspection.

What was the critical mistake made by Alan Irwin and his team during the inspection?

The critical mistake was that the pressurization mode selector was not set back to auto after performing the on-the-ground pressurization leak check.

Why was Captain Hans Jurgen Merten fired from his previous job at Jet2?

Hans Jurgen Merten was fired for repeated failures to comply with standard procedures.

What was the consequence of the pilots not noticing the pressurization mode selector was still on manual?

The cabin was not automatically pressurizing, leading to a situation where the air was getting thinner and there was increasingly less oxygen available.

What was the misinterpreted alarm that the pilots received at 12,000 feet?

The pilots misinterpreted the cabin altitude warning alarm as an erroneous takeoff configuration warning.

Why did the crew and passengers lose consciousness on Helios Airways Flight 522?

The crew and passengers lost consciousness due to rapid onset hypoxia caused by inadequate cabin pressurization and lack of oxygen.

What was the final fate of Helios Airways Flight 522?

The flight collided with the terrain just outside of Grammatico village, resulting in the loss of all 121 lives on board.

What were the charges brought against Helios officials, including Alan Irwin, after the accident?

Helios officials, including Alan Irwin, were charged with manslaughter after a legal battle with the Greek courts.