The incidents surrounding the crash of Helios Airways flight 522 on August 14, 2005, stand out as an extraordinary and bewildering aviation accident within the context of the 21st century. This particular tragedy involved a Boeing 737-300 aircraft that tragically descended near Grammatiko, located in the eastern region of Greece.
However, the circumstances surrounding this event are highly intriguing, as it is often referred to as a “ghost plane.”
Now, the question arises: what factors contributed to the crash of this enigmatic flight?
The Truth Behind the Helios Airways Flight 522
Helios Airways Flight 522, a regularly scheduled passenger flight with a planned route from Larnaca, Cyprus, to Prague, Czech Republic, including a layover in Athens, Greece, experienced a loss of communication between air traffic control (ATC) and the aircraft, named Olympia, shortly after take-off on August 14, 2005.
Tragically, the plane eventually crashed near Grammatiko, Greece, devastatingly losing all 121 passengers and crew on board. This incident is the most fatal aviation accident in the history of Greece.
The subsequent investigation carried out by the Air Accident Investigation and Aviation Safety Board (AAIASB) determined that the flight crew had overlooked the crucial step of setting the pressurization system to automatic during the pre-flight checks.
Consequently, the aircraft remained unpressurized throughout the flight, leading to generalized hypoxia among nearly all occupants and resulting in what is commonly known as a ghost flight. The accident’s negligent nature prompted legal action against Helios Airways and Boeing, and the government of Cyprus subsequently revoked the operating license of Helios Airways the following year.
The Disturbing Incidents That Occurred Before the Helios Airways Flight 522 Crash
During a previous flight on 16 December 2004, the aircraft encountered a sudden loss of cabin pressure, prompting the crew to initiate an emergency descent. The cabin crew informed the captain that there had been a loud noise from the aft service door and that a hole, roughly the size of a hand, was visible in the door’s seal.
The Air Accident and Incident Investigation Board (AAIIB) of Cyprus investigated the incident but was unable to determine the exact cause definitively. However, two possibilities were identified: an electrical malfunction that resulted in the opening of the outflow valve or the inadvertent opening of the aft service door.
The mother of the first officer who tragically lost his life in the subsequent crash claimed that her son had repeatedly complained to the captain about the aircraft becoming cold. Passengers also reported issues with the air conditioning during Helios flights. In the ten weeks leading up to the crash, the aircraft’s environmental control system underwent seven repairs or inspections.
In a separate incident in 2003, a Boeing 737 flying from Marseille Airport to Gatwick Airport experienced a cabin-wide pressurization fault. The flight crew noticed initial discomfort in their ears, followed by the activation of the cabin altitude warning horn, indicating that the cabin altitude had exceeded 10,000 feet (3,000 m).
The cockpit gauge showed a continuous increase in cabin altitude. Subsequently, both the primary AUTO and secondary STBY modes of the pressure control system failed. The crew switched to the first manual pressure control mode but were unable to effectively regulate the cabin altitude.
As a result, an emergency descent and diversion to Lyon were performed. The investigation traced the pressurization control system failure to burnt electrical wiring in the area behind the aft cargo hold.
The wiring had been damaged over time, potentially due to contact with a p-clip or a “zip” strap, which caused exposure of the conductors, leading to short circuits and subsequent wire burning. No other damage was reported. The wiring loom in question serviced all modes of operation for the rear outflow valve and other related systems.
Prelude to a Disaster: The Helios Airways Flight 522 Crash
The ill-fated aircraft involved in this tragic accident was initially registered as D-ADBQ and identified as a Boeing 737-300. Its maiden flight took place on December 29, 1997, and DBA operated it from 1998 until 2004.
Subsequently, it was leased by Helios Airways on April 16, 2004, and underwent re-registration as 5B-DBY, bearing the nickname “Olympia.” Alongside the aircraft that met its unfortunate fate, Helios Airways also possessed two leased Boeing 737-800s and an Airbus A319-100, which were added to its fleet on May 14, 2005.
The aircraft arrived at Larnaca International Airport at 01:25 local time on the day of the accident. The scheduled departure time from Larnaca was 09:00, with the destination being Prague Ruzyně International Airport.
The flight plan included a stopover at Athens International Airport, where the aircraft was expected to arrive at 10:45. Captain Hans-Jürgen Merten, a 58-year-old German contract pilot hired by Helios for holiday flights, served as the flight’s captain. With 35 years of experience (previously with Interflug from 1970 to 1991), Captain Merten had accumulated a total of 16,900 flight hours, including 5,500 hours specifically on the Boeing 737.
The first officer, Pampos Charalambous, a 51-year-old Cypriot pilot, had exclusively flown for Helios for the past five years, amassing a career total of 7,549 flight hours, with 3,991 of those hours on the Boeing 737. Due to a colleague’s illness, Louisa Vouteri, a 32-year-old Greek national residing in Cyprus, replaced them as the chief flight attendant.
What Caused the Horrifying Crash of the Helios Flight 522?
Upon the aircraft’s arrival at Larnaca from London on the day of the accident, the previous flight crew reported issues with a frozen door seal and abnormal noises emanating from the right aft service door.
They requested a thorough inspection of the door, which a ground engineer conducted. As part of the inspection, a pressurization leak check was performed. To carry out this check without relying on the aircraft’s engines, the pressurization system was temporarily set to “manual.”
Unfortunately, the engineer neglected to reset it to the standard “auto” setting upon completing the test.
Following the aircraft’s return to service, the flight crew inadvertently overlooked the state of the pressurization system on three separate occasions: during the pre-flight procedure, the after-start check, and the after-take-off check.
Despite these checks, no one in the flight deck noticed the incorrect setting. Consequently, the aircraft took off at 09:07 with the pressurization system still in the “manual” mode and the aft outflow valve partially open.
During the ascent, the cabin pressure gradually decreased, reaching a critical point when the aircraft reached an altitude of 12,040 feet (3,670 m). The cabin altitude warning horn was activated at this juncture.
However, rather than recognizing it as a signal to cease climbing, the crew misinterpreted it as a take-off configuration warning, which typically indicates that the aircraft is unprepared for take-off and can only be triggered on the ground.
Regrettably, the auditory alert for both warnings was indistinguishable.
Several warning lights illuminated the cockpit’s overhead panel within the following minutes. One or both of the equipment cooling warning lights came on, indicating inadequate airflow through the cooling fans due to decreased air density.
The activation of the master caution light accompanied this. The passenger oxygen light was also triggered, causing the oxygen masks in the passenger cabin to automatically deploy when the aircraft reached an altitude of approximately 18,000 feet (5,500 m).
Shortly after the cabin altitude warning sounded, the captain contacted the Helios operations center and reported that the “take-off configuration warning” was on and that the “cooling equipment” was functioning normally with the alternate system offline.
The captain also conversed with the ground engineer, repeatedly stating that the “cooling ventilation fan lights were off.” The engineer, who had previously conducted the pressurization leak check, inquired, “Can you confirm that the pressurization panel is set to AUTO?”
However, impaired by the initial symptoms of hypoxia, the captain disregarded the question and instead asked, “Where are my equipment cooling circuit breakers?” This marked the final communication with the aircraft.
The aircraft continued to climb until it leveled off at FL340, roughly 34,000 feet (10,000 m) above sea level. Between 09:30 and 09:40, Nicosia Air Traffic Control (ATC) made repeated attempts to establish contact with the aircraft but received no response.
At 09:37, the aircraft transitioned from the Cyprus Flight Information Region (FIR) into the Athens FIR without establishing contact with Athens ATC. Despite 19 additional attempts to communicate with the aircraft between 10:12 and 10:50, no responses were received.
At 10:40, while still maintaining FL340, the aircraft entered a holding pattern for Athens Airport, specifically at the KEA VOR. The autopilot maintained control of the aircraft within the holding pattern for the next 70 minutes.
At this stage, the Greek military decided to intervene, prompted either by air traffic control or by their own suspicion of a possible terrorism incident. At 11:05, two F-16 fighter aircraft from the Hellenic Air Force 111th Combat Wing were scrambled from Nea Anchialos Air Base to establish visual contact.
They intercepted the passenger jet at 11:24 and observed that the first officer was motionless, slumped over the controls, while the captain’s seat remained unoccupied. They also noted that the oxygen masks in the passenger cabin were hanging down.
At 11:49, flight attendant Andreas Prodromou entered the cockpit and occupied the captain’s seat, having managed to stay conscious by utilizing a portable oxygen supply. Prodromou’s girlfriend, Haris Charalambous, who was also a flight attendant, was seen assisting him in attempting to control the aircraft.
While Prodromou held a UK Commercial Pilot License, he lacked the qualifications to fly the Boeing 737 under such circumstances. Briefly waving at the F-16s, Prodromou’s presence in the cockpit was short-lived, as the left engine flamed out due to fuel exhaustion.
Consequently, the aircraft departed the holding pattern and commenced a descent. Crash investigators determined that Prodromou’s experience was insufficient to regain control of the aircraft given the circumstances.
However, he managed to maneuver the plane away from Athens and towards a rural area as the engines flamed out, ensuring no ground casualties. Roughly ten minutes after the loss of power from the left engine, the right engine also flamed out.
Shortly before 12:04, the aircraft crashed into hills near Grammatiko, approximately 40 km (25 mi; 22 nmi) from Athens, resulting in the tragic loss of all 121 passengers and crew members on board.
Onboard the aircraft were a total of 115 passengers and a crew of six individuals. Among the passengers, 67 were scheduled to disembark at Athens, while the remaining passengers were traveling to Prague.
Following the tragic crash, the bodies of 118 individuals were recovered from the scene. The passenger manifest consisted of 93 adults and 22 children, with the majority being Cypriot nationals (103) and the remaining 12 being Greek nationals.
Investigating the Terrifying Helios Airways Flight 522 Crash
Following the crash, the flight data recorder and cockpit voice recorder were sent to the Bureau of Enquiry and Analysis for Civil Aviation Safety in Paris. The cockpit voice recorder (CVR) recording proved instrumental in identifying Andreas Prodromou, a flight attendant who bravely entered the cockpit in an attempt to save the aircraft.
Prodromou made five distress calls, using the word “mayday,” but since the radio was still tuned to Larnaca and not Athens, his pleas for help went unheard by air traffic control (ATC). His voice was later recognized by colleagues who listened to the CVR recording.
Tragically, many of the recovered bodies were severely burned, making identification challenging. Autopsies conducted on the crash victims revealed that they were all alive at the time of impact, although it could not be determined whether they remained conscious.
In the Boeing 737 model involved in the accident, the emergency oxygen supply in the passenger cabin relies on chemical generators. These generators release enough oxygen, through breathing masks, to sustain consciousness for approximately 12 minutes.
This duration is typically considered adequate for an emergency descent to an altitude of 10,000 feet (3,000 m), where the atmospheric pressure is sufficient for humans to maintain consciousness without additional oxygen. Cabin crew members have access to portable oxygen sets with significantly longer durations.
The Hellenic Air Accident Investigation and Aviation Safety Board (AAIASB) identified the direct chain of events that led to the accident as follows: the pilot’s failure to recognize that the pressurization system was set to “manual,” the crew’s inability to identify the nature of the problem accurately, the incapacitation of the crew due to hypoxia (oxygen deprivation), eventual fuel exhaustion, and the subsequent impact with the ground.
After the incident, Helios Airways announced on 29 August 2005 that their Boeing fleet had successfully undergone safety checks and was cleared to resume service. The company later rebranded and changed its name to αjet.
However, approximately a year later, the authorities in Cyprus detained the airline’s aircraft and froze the company’s bank accounts. As a result, αjet announced that it would cease operations on 31 October 2006.
In the aftermath of the crash, several fake photographs circulated, claiming to depict the Helios Flight 522 aircraft during its interception by the Hellenic Air Force. These images, showing a Boeing 737 accompanied by F-16s, were later revealed to be fabricated.
The aircraft depicted in the images was actually 5B-DBH Zela, a Boeing 737-800 that was in service with Helios Airways at the time of the incident. The differences between the actual crashed aircraft (Boeing 737-300) and the depicted one (Boeing 737-800) could be observed in features such as overwing exits, fuselage length, and trailing edge wingtips.
In March 2011, the United States Federal Aviation Administration (FAA) issued an Airworthiness Directive mandating the installation of two additional cockpit warning lights on Boeing 737 aircraft from the −100 to −500 models.
These warning lights were designed to indicate problems related to take-off configuration or pressurization. Aircraft registered in the United States were required to have these additional lights installed by 14 March 2014 as per the FAA directive.
The Lawsuit Against Helios by the Families of the Victims
On 24 July 2007, families of the victims filed a lawsuit against Boeing. The lawyer representing the families, Constantinos Droungas, criticized Boeing for implementing the same alarm for two different types of malfunctions.
He also mentioned previous incidents involving similar problems on Boeing aircraft in Ireland and Norway. The families sought compensation of 76 million euros from Boeing. The case against Boeing was ultimately settled out of court.
In early 2008, an Athens prosecutor charged six former employees, including three Cypriots, two Britons, and one Bulgarian, with manslaughter in relation to the incident.
On 23 December 2008, Helios Airways and four of its officials were charged in Cyprus with 119 counts of manslaughter and causing death by recklessness and negligence. The trial commenced in November 2009, with state prosecutors concluding their case in June 2011.
On 21 December 2011, the case was dismissed, and the defendants were acquitted. The judges ruled that there was no causal association between the defendants and the negligence they were charged with for the fatal accident.
The Cypriot Attorney-general filed an appeal, and in December 2012, the Supreme Court overturned the acquittal, ordering a new trial. However, the retrial was subsequently dropped under double jeopardy rules, as the charges had already been heard in Athens.
In December 2011, a new trial began in a Greek magistrate’s court, involving chief executive officer Demetris Pantazis, flight operations manager Giorgos Kikkides, former chief pilot Ianko Stoimenov, and chief engineer Alan Irwin.
All were charged with manslaughter, with the exception of Irwin, whom the Cypriot authorities had acquitted. In April 2012, all except Irwin were found guilty and sentenced to 10 years imprisonment. They remained free on bail pending an appeal.
By 2013, Alan Irwin’s appeal was successful, while the other defendants’ appeals were rejected. The original 10-year sentence was upheld, but the defendants could buy out their sentence by paying around €79,000 each.
Ianko Stoimenov was not required to serve time in jail following the intervention of the Bulgarian government, which believed he was innocent.
Greek investigators attributed the crash of Helios Airways flight to human error, as the aircraft failed to pressurize after taking off from Larnaca Airport. Both Cyprus and Greece prosecutors blamed airline officials for disregarding safety procedures and failing to address concerns about the pilots’ qualifications.
Relatives of the victims filed a class-action lawsuit against the Cypriot government, specifically targeting the Department of Civil Aviation, for negligence that contributed to the air disaster. They alleged that the DCA had overlooked airlines’ lax regulations enforcement and generally prioritized cutting corners in-flight safety.
The story of Helios Airways flight 522 is tragic and captivating. It contains elements that seem straight out of a movie script, with its bizarre premise and dramatic turn of events. However, it is important to remember that this was not a fictional tale but a real-life tragedy.
Andreas Prodromou, the flight attendant on board, found himself in an unimaginable situation. He was unable to save the plane, and even if he had somehow succeeded, he would have been the sole survivor. The reality of the situation was far from a Hollywood ending.
One can only wonder about the thoughts and emotions Prodromou experienced as he moved through the aircraft, surrounded by the lost souls of the passengers and crew. He must have felt a profound sense of loneliness, both physically and spiritually, enduring a unique form of a nightmare that no one else had ever experienced before or since.
Despite the overwhelming odds against him, Prodromou did his best, perhaps believing that he held his own life and the lives of 120 others in his hands, even though they were beyond saving. In the face of such adversity, his courage and determination make him a hero.
Not all heroes succeed in their endeavors; sometimes, heroism means fighting until the end, even when the outcome is inevitable.
The story of Helios Airways Flight 522 serves as a reminder of the unpredictable and often tragic nature of real life. It is a testament to the bravery of those involved and the enduring impact of such events on the collective memory of humanity.
Next, read about the Disturbing Disappearance of Louis Le Prince, the Man Killed By Thomas Edison. Then, The Tragic Tale Behind the Tenerife Airport Disaster Awaits You! Have a great flight!
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