quarta-feira, 27 de abril de 2022

EGYPTAIR FLIGHT 804 CRASH - The pilot's lit cigarette combined with leaked oxygen

 



EgyptAir flight from Paris to Cairo crashed in 2016, killing all 66 people on board.

April 26, 2022

When the Airbus A320 disappears the first thought is to a terrorist attack.

Airbus A320, registered SU-GCC, died when it crashed into the Mediterranean Sea. Egyptian authorities have never published a final report into the crash. 

French air accident investigators from the BEA stated on July 6, 2018 that they considered “the most likely hypothesis is that a fire broke out in the cockpit while the airplane was flying at its cruise altitude and that the fire spread rapidly resulting in the loss of control of the airplane.” 

The captain or first officer had been smoking at 37,000ft shortly before the crash.

In a 134-page official report, which was sent to the Court of Appeal in Paris last month, investigators said the fire may have broken out in the cockpit due a combination of a lit cigarette and the escape of oxygen from the co-pilot’s mask.

The fire started after the pilot's lit cigarette combined with leaked oxygen, the report said.




A 134-page document submitted to the Court of Appeals in Paris last month said investigators determined that the burning cigarette combined with escaping oxygen from the co-pilot's mask and caused a fire on board Flight 804.

The French air accident investigation agency had said previously that a cockpit fire likely caused the crash; Egyptian authorities initially claimed it was a terrorist bombing. 

The French BEA air accident investigation agency has previously said the crash was probably caused by a cockpit fire, contradicting an earlier suggestion by Egyptian authorities that a bomb may have been the cause.

It also said that authorities in Egypt had apparently not followed up calls for further investigations. {ID:L8N1U306X]

The two experts commissioned by French judges in charge of the dossier highlighted some twenty warnings pointing to recurring faults during the plane's five flights before the crash.

Before disappearing from radar — and shortly after leaving Greek airspace — flight MS804 signals through the automatic system the presence of smoke in the front bathroom and in the lower part of the nose. Pilots do not launch any may days. The Airbus A320 is one of the most used and safe aircraft in the world. Thousands fly every day. But six years after that tragedy, the Egyptian authorities — leading the investigation by jurisdiction — have never produced any final investigation report, as advocated by international treaties. And not even preliminary.

Above Italy

At 00.11 on May 19, the jet enters Italian airspace over Livigno, a few minutes later it leaves the country from Veneto, then skirts all the Balkans and proceeds further and further south. At 01.24 — reconstruct the tracks of the specialized site Flightradar24 — he enters Greek airspace, but an hour later neither the Greek controller nor the Egyptian one manage to get in touch. At 2.30 am the Airbus disappears from the radars of both area control centers after turning a couple of times first to the left, then immediately to the right.

The seven signals

Shortly before sinking, it turns out later, the plane sent seven "dispatches" in just two seconds through the "Acars", a data communication system with the ground stations: they signal problems with the anti-icing sensors, the windows of the cockpit, the presence of smoke in the front bathroom and in the avionics compartment (under the cockpit), the stop to the operation of two computer systems crucial for flight and the one that maneuvers the wings. Neither the commander nor the first officer mentions it or asks for assistance.

The start of the investigation

Relations with the Egyptians are immediately problematic. The incident, for Cairo, is an act of terrorism and for this reason the investigation requires the acts to be secreted. The transalpine authorities find it difficult to support these theses. The dynamics of the recovered debris around the impact area, according to Western experts, excludes the explosion at altitude. The truth lies in the two black boxes, found and analyzed in the laboratories near Paris of the investigative body French Bea. But the intergovernmental agreement provides that Bea cannot disclose the information because it is not responsible for the investigation. A search warrant from the French judiciary is needed to obtain the data of the black boxes that remain known only to very few people. "From the Egyptians we received only the ritual condolences and the remains of our loved ones. Then the silence,"

The counter-investigation

A 76-page document, prepared between 2018 and 2019 by two French experts, claims that in the five previous flights that aircraft recorded about twenty warnings for more or less important technical problems – from the air intake system into the engines to the smoke detection sensors on board – "which, however, were not reported by the pilots and therefore not analyzed by EgyptAir maintenance", it reads. Egyptian civil aviation denies the existence of technical problems. "Before its penultimate flight (from Cairo to Paris, ed) the plane should not have taken off without extensive control," the two experts write. However, they conclude that it is not possible to identify a root cause.

The French version

A spokesman for Bea explains that the official position of the investigative body French remains that of July 6, 2018. With a press note – at times very harsh – the agency claims that "the most likely hypothesis of the accident is that it was caused by a fire that broke out in the cockpit during the cruise phase, which spread quickly leading to the loss of control of the aircraft". Bea also points out that "it is necessary to have a final report of the incident in order to be able to present the differences of opinion to the Egyptians as established by international norms". Having this document also serves to improve safety in the sector as it always happens after every tragedy of the skies.

Without effective cooperation from Egypt, without being able to hear the people involved in the maintenance, it becomes almost impossible to get to the bottom of this story."

Traces of oxygen

Separating the sound tracks of one of the black boxes, the "Cockpit voice recorder", the experts discover two rustles at 2.25 and 24 seconds and at 2.25 and 29 that come from the microphone embedded in the oxygen mask of the co-pilot who at that moment is in his compartment. Then two more blows, at 2.26 and 11 and at 2.26 and 24. Oxygen itself is not flammable, but promotes combustion. For this reason, immediately afterwards there is a principle of fire unleashed "by a spark or a flame". The finger is pointed at a lit cigarette, the umpteenth in that aircraft if it is true that two months earlier in the cockpit the ashtrays were replaced because they were now too used. The document cannot determine whether the pilots used a fire extinguisher or not.

The checks envisaged

"When we enter the cockpit among the various preliminary checks before taking off there is also that of controlling the flow of oxygen in the side masks", explains Daniele Veronelli, commander of A320 and member of the technical department of Anpac (National Association of Commercial Aviation Pilots) to the Courier. "You raise a door and test the air flow by pressing a button that pops out of the compartment. By operating the intercom you can feel the oxygen flowing because each mask is equipped with a microphone». If the crew is the first to set foot in the plane that day - he continues - "then this type of test is also carried out. If, on the other hand, you take over from your colleagues, the control is not provided, but nothing detracts from the fact that this is performed the same, it takes a few seconds».

 

Alarms

Are there oxygen signals on board? "When the levels drop, in one of the screens in front of the pilots the indication of the amount of oxygen is colored orange. If you are on the ground you do not take off, if you are in flight you have to decide whether to continue or divert to the nearest airport». The masks have a minimum of 15 minutes of autonomy. "There is a lever: if it is in the normal position the flow of oxygen is on demand. If, on the other hand, it is in the "emergency" position then it releases the air at a greater pressure to throw out of the mask the fumes that could enter in case of fire or smoke on board.

The tiredness of the pilots

In the document, among many things, there is a passage about pilots. Between 1.01 and 1.46 at night — when the aircraft passes between the coast of Croatia and over Athens, Greece — the technicians note, hearing the black boxes, that the commander and first officer show signs of fatigue. "A yawn is clearly audible at 1.01 and 53 seconds," it reads. Twelve minutes later "pilot and co-pilot clearly express that both feel tired from this night flight and lack of sleep." Same concept repeated at 1.46. But the documents compiled, the experts explain, "indicate that the rest times for both have been respected".

ICAO, the UN civil aviation agency, explains that it has not received any final report from Cairo. Bea, the investigative agency French, confirms the position expressed in 2018: for them the most likely hypothesis remains "a fire that broke out in the cockpit during the cruise phase that led to the loss of control of the jet".





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