Boeing Is Covering Up Another Fatal MAX Flaw

A commercial airline pilot who analyses plane crashes is warning that another fault in the Boeing 737 MAX is in danger of causing the next catastrophic crash, and nothing is being done about it.

While it’s a bit left field compared to my usual writing, I felt compelled to write something after watching this pilot’s warning. I’ve also written previously about Boeing in the context of actions without consequences, so maybe it’s not that left field.

In any case, it seems especially important right now given that planes have begun falling out of the sky on an almost weekly basis since Trump and Musk took over and began the mass firing of Federal Aviation Authority staff.

The pilot, Petter Hornfeldt, is a senior captain who flies for Ryanair and publishes videos on YouTube and Instagram to his nearly two million followers. Hornfeldt says the problem relates to the sequence of events following a bird strike (or the failure of one of the fan blades independent of a bird strike) to the engines fitted on the accident-plagued and once-grounded MAX.

While bird strikes causing engine failures are common, they rarely result in a crash. Jet engines are designed to withstand these events and compensate for them. When these mechanisms don’t work, however, it can result in a crash. Bird remains were found in the engines of the Jeju Air Boeing 737 which overshot the runway and slammed into a perimeter wall in Korea in December, killing all 179 people on board. And famously, the plane that landed on the Hudson river in New York in 2009 did so because birds were sucked into both engines, causing a total loss of power.

In the case of the MAX, the failure of the engines per se, and the subsequent loss of thrust is not the problem. The problem is what happens to the oil within the failed engine, where it is routed and where it ends up—the air conditioning system.

When it was launched in 2017, the Boeing MAX was touted as the most fuel efficient, medium-sized workhorse commercial jet in the world. This was largely because of the design of its new LEAP engines, manufactured jointly by America’s GE Aerospace and France’s Safran Aircraft Engines. To maximise fuel efficiency, the new engine moves a larger quantity of air more slowly through the engine than previous commercial jet engine designs. It does this by incorporating fewer - eighteen as opposed to twenty-four - but comparatively much wider fan blades than prior models.

Efficiency is the holy grail for airlines. If you can shave off even a tiny percentage of fuel cost on every flight, this means bigger profits and therefore juicier dividends and rewards for bosses and shareholders. For Boeing, this efficiency would drive sales of the MAX and help them outcompete Airbus on the medium-sized airframe to reclaim their place as the number one aircraft manufacturer in the world.

But in the name of efficiency, these engines come with a problem. If one of eighteen larger fan blades should break, it creates a far greater load imbalance than if one smaller blade in twenty four should break. Just a basic principle of physics. This imbalance then produces more severe vibrations than on a smaller engine, generating more load on the ball bearings, fittings and the frame, threatening the integrity of the entire engine.

To get around this problem, the engine makers implemented what they call the load reduction device, or LRD. When it senses vibrations above a certain level, the LRD activates, purposefully jettisoning weaker components, disconnecting the fan from the engine core, allowing the blades to find a new centre of rotation and reducing vibrations to a safe level. A clever fix perhaps, but, during the process of this re-centering, engine oil is released into the core of the engine where it is aerosolised by high temperatures. The problem with this is that on many airplanes, the air that enables us to breathe at 30,000 feet is drawn through the engines. Normally not a problem, but the activation of the LRD and the release of the fuel contaminates the normally pure air being pulled into plane with highly toxic aerosolised engine oil, which enters the passenger cabin and cockpit as acrid white smoke.

And that’s exactly what happened during two flights in May and December 2023, one flying from Cuba to Fort Lauderdale and the other from New Orleans to Tampa. Both were Boeing 737-MAXs operated by Southwest Airlines, and both had to make emergency landings after the plane was filled with smoke.

This isn’t just any smoke however. Analysis by an FAA investigation team showed that it contained high concentrations of acrolein and formaldehyde which in the confines of the cockpit, the investigators said ‘may exceed potentially lethal levels in just 39 seconds.’ Both of these compounds are carcinogenic and formaldehyde is highly neurotoxic. A comment by a retired commercial pilot on Hornfeldt’s YouTube video about this also mentions that jet engine oil contains tri-cresyl phosphate, a highly toxic nerve agent.

Another comment by a physician who says they have practical experience in aviation medicine said that ‘no one wants to discuss the topic because, in the end, it would always lead to abolishing the current bleed air system in favour of a compressor system like that used in the 787.’ In other words, the air you breathe in a plane would be a lot safer if it was drawn from a completely separate system, rather than through the engines. The post continues:

Oil aerosols are generally toxic, esp. neurotoxic, and carcinogenic. When lubricants are heated, burned, or aerosolized, they enter the bleed air system and, depending on the concentration, can quickly poison the crews or cause long-term harm. Acrolein is a Category 3 carcinogen, highly irritating and toxic, but it is only one of hundreds of substances, of which only a small fraction have been studied. However, because the interval between exposure and the onset of disease is long, a causal connection can still be easily concealed.

The FAA investigators recommended a series of fixes including a design change as soon as possible. But here’s the wild thing. When the FAA board tasked with issuing legally binding airworthiness directives on the basis of their own investigators work met (Biden’s FAA, we should note), they decided no immediate action needed to be taken. So naturally, without being compelled, neither Boeing or the engine manufacturer have taken any real action.

To compound all of this, Boeing fails to mention the LRD system in the pilot handbook. It was the failure to mention a critical new system within the design of the MAX that was a major cause of the two Boeings that spiralled uncontrolled to the ground in 2018 and 2019 killing hundreds of people, crashes which led to the four-year grounding of the MAX.

I’ve watched a lot of Hornfeldt’s videos. He’s incredibly measured and not in the least bit prone to alarmism. For him to make a video like this is out of character and is a major red flag about the danger this system poses. In the video Hornfeldt says no airline in the world is training pilots how to deal with an engine failure and a severe smoke event like that produced by the LRD system.

The LEAP engines are also used on new Airbuses and other Boeings. But it is the combination of the LEAP engines and the Boeing 737 air pressurisation system that appears to be at fault. However, as Hornfeldt explains in the video, the larger extent of the problem is basically unknown. Is it confined to the MAX or more widespread? All we know is that the only two planes to have experienced this problem so far are these two MAXs. Because of the way Boeing and the FAA have responded, we also know that many thousands of pilots and millions of passengers have no idea about the potential dangers of flying in these airplanes.

In a further ominous twist, Hornfeldt says the rumours are that the lead FAA investigator on these incidents has now been sacked. (If you’re the online type, you’ll know social media lit up with theories when Boeing whistleblowers started dying.)

I started out saying this was left field article for me, but of course it isn’t.

This is about capitalism, profits and business-as-usual being prioritised over human life. About warnings unheeded until inevitable disaster strikes. It is about power, and the impunity felt by a company that is too big to fail, too integrated into the American security and defence architecture to be allowed to fail. A company which, in the name of cost-cutting and efficiency, has recently killed many hundreds of people without any meaningful punishment.

It is also about the health dangers that linger in the air all around us, both on the ground and thousands of feet in the sky.