The many human errors that brought down the Boeing 737 Max
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It would probably take either an inquiry like those into the space shuttle accidents, or a whistleblower, to know whether anyone was raising concerns. I can believe it is possible that everyone was convinced by the "in the worst case, it is no worse than ordinary trim runaway" argument (which does not excuse the failure to meet the redundancy requirement), but then the Ethiopian Airlines crash, and its crew's inability to manually re-trim, might raise the question of whether trim runaway on any 737 model is more of a risk than had been supposed (to be fair, trim runaway has not caused 737 crashes in the past, AFAIK.)
They were the only ones, who really knew the inside details and they were the only ones to know how to (possibly) fix it before a lot more people had to day.
Instead of being completely fortright and transparent they published an apparently completely worthless checklist. And all in the name of greed and corporate profit.
That they still smear the pilots and throw them under the bus despite all the facts that came to light leaves me speechless.
I don't see why Boeing would pay to have this published.
The conclusion is most charitably described as fanciful. There are strict rules about an automated system being able to apply more "authority" than the pilot can counter, which every engineer and manager involved knew well.
There are strict rules about a single sensor failure that can make the plane unflyable, which all knew well.
This is not a case of simple negligence to check documentation. This is a case of deliberate coverup of known risk factors to dodge rules specifically intended for airframe changes of this kind.
It was the process of dodging these rules which kept the MCAS design from being reviewed competently.
[1] https://www.seattletimes.com/business/boeing-aerospace/a-lac...
[0] https://www.youtube.com/watch?v=NhZ0D-JRtz0
[1] https://en.wikipedia.org/wiki/Boeing_737_MAX#Maneuvering_Cha...
TLDR/TLDW: AoA sensor measures "angle of attack." AoA sensors are physically over-engineered, but the electrical components may be questionable. If an AoA sensor fails, it may cause a stall. The 737 Max is equipped with two sensors, however, effectively utilized only one at a time because it cost extra for the "AOA-disagree" feature.
> effectively utilized only one at a time because it cost extra for the "AOA-disagree" feature.
Yeah, props to Boeing who put a basic security feature as an "extra cost" option. But hey, who needs to know their AoA sensors are failing, especially when the plane is commanded by that, right?
For example, when I was designing a home weather station for myself, I wondered if the anemometer and wind vane could be replaced with ultrasonic sensors and emitters. If you take four ultrasonic emitter/ultrasonic sensor pairs and arrange them in a square, and measure the time of flight of four pulses, one from each corner emitter to the diagonally opposite sensor, you can determine the component of the wind vector along that diagonal. Combine the components from the diagonals, and you get the wind vector.
A bit of research turned up that this was not an original idea, and it does work. There are commercial anemometers and wind vanes (are they still called wind vanes when they don't have a vane?) for terrestrial use that work this way. There have also been many home made ones, such as this one [1].
Offhand, I don't see why such a thing would not work for an airplane.
[1] http://embedded-lab.com/blog/making-an-ultrasonic-anemometer...
Its possible failure modes, too, seem a lot more complicated than for a physical vane.
"The AOA tube is constructed with two tiny machined holes to create differential pressure sources. One hole is bore-sighted at the front of the AOA tube along the longitudinal axis, while the second, located at the bottom of the AOA probe, is pointed downward at a 45-degree angle to act as a reference source.
"Garmin’s normalized AOA includes an additional static-air-pressure source to allow the air-data computer to calculate airspeed and air density, important in calculating precise AOA. The addition of the static-pressure reference input makes the AOA indication accurate regardless of the airplane’s weight, speed or configuration."
[1] https://www.flyingmag.com/how-it-works-angle-attack-indicato...
It has to in order to get anything certified at all, says Jon Ostrower, editor-in-chief of The Air Current and a former aviation reporter for The Wall Street Journal. Boeing already has the people and the expertise, it pays better, and it isn’t susceptible to government shutdowns. The FAA, meanwhile, says it would need 10,000 more employees and an additional $1.8 billion of taxpayer money each year to bring certification entirely in-house."
I wonder if therein lies the solution. Allocation of some of the budget there instead of military perhaps? Not to mention the policy paralysis leading up to stupid government shutdowns putting people at risk.
Department of Defense : $574 billion
Department of Veteran Affairs :$78.9 billion
Department of Education : $68.2 billion
Department of Health and Human Services :$65.1 billion
Environmental Protection Agency: $5.7 billion
Does this not seem off to you?
Mandatory spending: $2.841 trillion (this includes the following)
Social Security: $1.102 trillion
Medicare: $679 billion
Medicaid: $418 billion
The military budget isn't a whipping boy to just cut into every time you need money for something else. It's a priority for a lot of people in the US, whether you agree with them or not. If something like increasing the FAA budget is actually important, the metric to go by should be, "am I willing to cut social security and healthcare to pay for this?" Because that's what the government is actually spending money on, and that's where it would have to come from.
Serving the people does not have to cost service to the people. Serving the people does not have to be a zero sum game, when we could instead take from the excesses of violence against others to serve the people.
Looking at the raw numbers is ingenuous as well. As a percentage of GDP or government spending, the US doesn't even break the top 15 in the world on military spending.
Also, the US spends more on healthcare and social security than any other country. Why are you giving those careful white glove treatment?
The US is one of the most populous countries with any sort of widespread social welfare program. Those programs scale in cost with population size. There's no reason for military spending to also scale in the same way with population size. You aren't comparing the same things, so stop pretending you are.
* The original argument is that the US military spending is abnormally high, when considered as a raw dollar amount.
However:
* The US military spending is not actually abnormally high when considered as a percentage of GDP or Government budget.
* There's hypocrisy in only considering the military in raw dollar amounts, but considering health care and social security as a percentage or per capita expense.
* If you also consider social security and healthcare by their raw dollar amounts, you also end up with absurd levels of spending.
* You should be pinning spending for health care, social security, and military to the same per capita or GDP metrics, and only then be objecting to them if they're abnormally high.
* It's unethical to pick and choose what spending you personally object to, and then cherry-pick the method you judge that specific spending by to support your personal decision.
It would also make it easier for new competitors to enter the market since they would need to build/create one less structure.
And it could make flying safer since the regulator would see that Company A does X, and Company B should too.
Safe practices shouldn’t be a company secret, they should be viral.
There is more value from these lessons being be taught in MBAs, and I don't think they are.
No amount of engineering safety can overcome unsafe business leadership.
Take, for example, the Thiokol engineer who told Roger Boisjoly's wife that if the Challenger inquiry led to Thiokol's shutdown, he would leave his kids on Boisjoly's doorstep - was that sound engineering reasoning?
You also forgot Galloping Girdie. The Tacoma Narrows bridge.
That and the rudder reversal problems Boeing had back in the 90's.
Then there's the political dimension. Let's say there are Congressional hearings ongoing that are ripping apart the FAA to figure out if they delegated too much and why they missed stuff. Who would want to fly on a plane undergoing that kind of scrutiny?
There's also the possibility that the FAA would unground the plane but other countries do not. Usually, much of the rest of the world just trusts the FAA, this is likely to not be the case here. Even if it was ungrounded in the US, who would want to fly on a plane if its not approved to fly in Europe?