Aircraft Accidents and Lessons Unlearned LVIII: Egypt Air MS804

On May 19, 2016, Egypt Air flight MS804 (EA804), an Airbus A320-232, registration number SU-GCC, departed Charles de Gaulle Airport, France, bound for Cairo International Airport in Cairo, Egypt. Almost three and one-half hours later, the aircraft crashed into the Mediterranean Sea without any warning; no transmissions were made.

No final report was adopted - yet; no clear investigation was completed or, as it appears, conducted by a responsible authority. The latest indication of an investigation after almost six years were news articles stating that France’s Bureau of Enquiry and Analysis (BEA) for Civil Aviation Safety determined that the aircraft suffered a fire in the cockpit that was the result of a pilot smoking a cigarette near an oxygen mask with a leak.

I have worked with the BEA before on the American 587 A300 accident; their investigators were more observant in those days, surely in their attention to detail. I tried to acquire this March 2022 EA804 BEA report with the cigarette/leaky oxygen mask fire conclusion, but I was unable to find the report; all BEA reports concerning EA804 found were from 2020 or earlier. Instead, the only information available came from 2022 journalistic sources, all quoting the BEA’s findings. The consequences of the BEA’s EA804 findings, as reported, demand a response because this cockpit fire conclusion, without credible evidence to support it, creates confusion in the aviation industry, while giving authority to ignorance.

The first reporter noted was from the New York (NY) Post, which said that the BEA, “… has since concluded that captain Mohamed Said Shoukair’s mid-air smoke break led to a fire onboard the A320 jet when his cigarette ignited oxygen leaking from an oxygen mask in the cockpit.” The article went on to say, “But in March 2022, BEA released a new report that alleges that oxygen had leaked from a pilot’s oxygen mask in the cockpit shortly before the crash, based on black box data that captured the sound of the oxygen hissing. The oxygen mask in question had been replaced just three days before the fateful flight by an Egypt Air maintenance worker, but for an unknown reason it had its release valve set to the ‘emergency position,’ which, according to the Airbus safety manual, could lead to leaks.” The 134-page report was reviewed by Italian newspaper Corriere della Serra, which, though my Italian is rusty, is not an Italian aviation source but translates to the Courier of the Greenhouse. It is a good bet that a news journal known as the Greenhouse Courier did not ask pointed questions about the oxygen masks.

Another separate article in Plane and Pilot magazine mirrored the NY Post’s report except to say it was the first officer’s cigarette, not one belonging to the captain. Another circular, this one from Greece called the Greek Reporter, again, repeated the NY Post article almost verbatim. Another source of this same information was a web journal called One Mile at a Time, which added emotional-based comments from readers, which had nothing to do with the investigation and less to do with factual information.

The general understanding among these circulars was that one of the two pilots smoked a cigarette near a leaking oxygen mask valve which started the fire. In addition, the cockpit voice recorder (CVR) captured escaping oxygen sounds on the cockpit mic. This begs the question: How loud was this leak that the pilots did not hear it, but the CVR did?

For six years and numerous investigations, including Egypt Air and the Egyptian Civil Aviation Ministry, who both stand behind the-accident-was-a-terrorist-attack theory, the ‘investigations’ all have the earmark of indifference, a shrug of the shoulders, a roll of the eyes and a toss of the head. These investigators should have been more honest, expressed their lack of concern and effort from the beginning and spared the industry – and more importantly, victims’ families – six years of anguish.

I became aware of the cigarette explosion theory on LinkedIn and was disappointed at the lack of imagination exerted. A leaking oxygen line? An explosion from a cigarette being lit? The CVR caught the sound of escaping oxygen … and nothing else? If those who were attached to this accident tried harder beyond throwing darts at the Board of Probable Causes, they might have seen the holes in the analysis.

The CVR picked up the oxygen hissing but nothing else. No ignition; no spread of flame; no commotion. No words of surprise from the pilots. Could the hissing noise have been a fire extinguisher being discharged? Is that all that was heard, an ambiguous hissing noise that took six years to identify? It is a good bet a mechanic would have identified the hissing noise a lot earlier.

How explosive would aviator’s breathing oxygen (ABO) have been at 37,000 feet of altitude? Is ABO pure? Per the Federal Aviation Administration (FAA) sources, the bottled ABO, at its storage cylinder, is 100% pure. It is under pressure at between 1800 to 2000 pounds per square inch (PSI). The ABO is directed into the mask, which is sealed against the breather’s face to prevent smoke or bad air from outside diluting the pure oxygen and getting into the breather’s lungs. It is a separate system from the passenger oxygen system. Would, then, EA804’s ABO, that escaped through a leaking mask, be as potent as, say, the oxygen tents in a hospital intensive care unit (ICU)? Um, no, for specific reasons. This is why these journalist reports are disinformation, presenting the cockpit as some airtight chamber. People forget that 30 years ago, smoking was normal in the airliner, even the cockpit.

When visiting a patient in the ICU, the patient is in a tent, an enclosure, designed to envelope the patient in oxygen; the oxygen within the tent is pure – and isolated from the rest of the room. If the patient were to light a cigarette within the tent … BOOM!

Assume EA804’s oxygen mask was leaking – which is highly doubtful and a stretch to prove – would the ABO purity be maintained? No. There are mitigating factors, such as: the existing air in the cockpit; carbon dioxide exhaled by the pilots; instrument cooling systems’ airflow; air-conditioned air constantly pumped into the cockpit; the directional valves that directed the air-conditioned air throughout the cockpit; all these contributors diluted the oxygen’s purity outside the ABO system; they disperse the oxygen molecules and destabilize their flammability.

Besides, if a pilot was lighting up in flight, chances are there was no emergency at the time of the cigarette break. Oxygen masks do not just hang about the cockpit, draped across the back of the seat; they are stowed away in their cradles, isolated from any ignition source. This was why the chances of hearing oxygen ‘hissing’ were slim-to-none; the mask lines were safely protected off to the pilots’ sides. ‘Hissing’ would have been muffled. The oxygen masks checked at preflight would have been in NORMAL or diluter demand. This meant the ABO only dispensed to the pilot when the pilot inhaled and stopped during exhalation. Three junior aviation journalists said the oxygen mask had been replaced three days earlier, which would mean that numerous flight crews never checked the oxygen masks during their preflight. That seems like a critical point to bring forward.

Most importantly, a point that all the junior aviation journalists missed was – and if we are to believe, the BEA did as well – if the mechanic, who had replaced the oxygen mask, had indeed left the switch in EMERGENCY … three days earlier, how come the ABO cylinder was not empty? It only takes a matter of minutes before 2000 PSI of oxygen, leaking uncontrolled, depletes to zero, this from an old-time mechanic who has serviced his fair share of ABO cylinders. If EMERGENCY was indeed selected and left three days earlier, not just one or two pilots were not performing preflight checks, but every pilot who populated the accident aircraft cockpit between the oxygen mask replacement and the accident. Furthermore, mechanics were not performing adequate post flight checks and servicing ABO.

This is not a surprising development in the EA804 investigation because mechanics did not appear to have been questioned. Indeed, mechanics did not investigate the accident. This is common practice in aviation accident investigations because investigatory groups – including the National Transportation Safety Board – NTSB – refuse to employ qualified airframe and powerplant certificated technicians with experience as accident investigators to investigate maintenance issues in accident investigations.

If only this accident was investigated by serious-minded individuals. Instead, the aviation industry was knee-capped by politics and indolence; another enigmatic tragedy became a lesson forever unlearned; another probable cause that has resulted in one more indifferent shot from the hip. Too bad we can no longer be serious about serious things.