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stackola

Second 737 Max to go down within the span of a few months.

I hope it's a coincidence, but that can't look good on Boeing.

E: Removed the word 'sure'

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Giving the infrequency of airplane crashes, it probably isn't coincidence.

Very unlikely for a brand new plane to suffer issues with altitude shortly after take off.

Even less likely for it to happen twice in a span of a few months.

However, aviation history has more than a handful of samples where a new design suffered multiple crashes shortly after introduction and the cause was ultimately a design flaw.

Someone is probably pulling all of the flight logs for the 737 MAX right now and is going to see how many other non-fatal cases of altitude issues after take have been reported.

> "Giving the infrequency of airplane crashes, it probably isn't coincidence."

I don't think that's how statistics work. You need larger sample sizes in order to make such a statement with high confidence.

That depends on the size of the effect. The total loss of a modern airliner due to a control issue is so rare that we might indeed be there now, statistically.

1 event can be significant.

No. If you take a small sample size and you find the problem twice then it warrants a great deal of investigating. This is common in auditing for example.

Yes it warrants investigating. But it still more probably is a coincidence.

My wife, a civil engineer, loves all kinds of new things, especially new car models.

Me, the software engineer, am extremely paranoid with newly released models of any kind. I'd rather wait a few years for it to be tested, never being an early adopter for it.

Waterfall vs. Agile

The frighting thing is, I was just looking at tickets for that exact flight leg (but the opposite direction), for an upcoming trip this summer.

I am not flying any leg on the 737 Max now.

I was going to try to tell you that airplanes are extremely safe, that two highly publicized crashes in 8 months should be compared to a far larger number of unsurprising, non-newsworthy auto crashes...but there are only 330 total 737 Max planes flying, and two have crashed. Those aren't the numbers I expected.

That's an absolutely insane rate. They should all be grounded...

As I wrote earlier, I am not flying with 737 Max until this issue is going to be addressed.

I have 4 flights on 737MAX8 in the next couple weeks. Not feeling great about it.

I wonder whether those flights will happen on those planes. There are only a few hundred MAXs in existence, and now two new ones have failed. Grounding the fleet wouldn't feel like an overreaction to me.

Agreed. Debating booking a refundable ticket on another airline that doesn’t fly MAX in case of a grounding this week.

Looks like China's grounded all of theirs now.

Absolutely. However, which group would you belong to later on:

- the one that avoided flying MAXs and it turned out to be something else

- the one that avoided flying MAXs and it turned out to be a problem with the MAX

- the one that did not avoid flying MAXs and it turned out to be something else

- the one that did not avoid flying MAXs and it turned out to be a problem with the MAX

I think it is much safer to be in the first two and potentially being labeled paranoid later on worst case.

I'm not sure why you say "however" or think we disagree. Maybe you misread my "wouldn't feel like an overreaction" as "would feel like an overreaction"?

I agree with grounding the fleet, especially if it's the case that an MCAS software update was already being prepared but not yet deployed.

Yeah exactly that. :)

My condolences to your family. But seriously, this is concerning and I feel terrible for the people that lost their lives and their families. What a terrible way to go. I cannot even imagine.

If it makes you feel better, the pilots on those flights are probably going to be more careful than ever now given the incidents.

That should already have been the case after the first incident. I would guess and hope they'll be grounded until MCAS is significantly reworked, if it was the cause. This level of risk is completely off the charts for modern airliner aviation.

I sure hope so. I’m more hoping they ground the fleet.

I have been avoiding Boeings for years for different reasons, seems I am automatically protected against these ones too.

Just wondering, do passengers have an option to chose the model of plane they are flying? Not flown around much so just genuinely asking.

Is there a reliable way to tell which airplane type before booking?

Looks like it crashed at a very steep angle.

Previous crash was involving a stall prevention software overwhelming the pilot input.

It was said to be added to new 737 due to it getting slightly tail heavier, and as a safeguard to pilot overreacting to it feeling unusual.

And most crucially, this system can't be overridden using stick inputs whereas previous systems on the 737 were. And this change amongst others was kept relatively hidden by Boeing as a cost-savings measure, so that a 737 pilot can fly a new MAX without needing a new certification.

Is this true? Terrifying that a pilot can’t override the computer.

Wait until you learn about how the fly-by-wire system on Airbus works ;)

But A319/320/321s aren’t dropping out of the sky at an astonishing rate.

It may be the case that Airbus is simply better at building automation into the fabric of their aircraft from the ground up than Boeing.

Or that pilots in general do not know how to fly anymore. /s

That is probably true. Airbus pilots know and expect the computer to have the last word. Pilots of all planes are expected to know how to engage alternate law (more direct control) or disable specific parts of automation when necessary. I was going to say they are not doing too well at that, but then you only hear about it when they failed. In the same vein you don't hear much about automation saving lives.

I have a friend who is a commercial pilot and who doesn't like Airbus planes because he doesn't want to be overruled by a computer... Accident statistics are a wash between Boeing and Airbus, though.

It is possible override it, but pilots weren't trained on how.

https://www.king5.com/article/news/local/us-pilots-want-more...

I sure hope this additional training was provided after the Lion Air crash.

It can be overridden, but not solely using the stick. You have to press a button first.

The trouble is certification has been largely outsourced to the manufacturers. [0]

[0] https://www.seattletimes.com/seattle-news/faa-faulted-for-ou...

I'm sure self-signed certificates go down a treat here on hackernews.

Lion Air was a very steep, high energy impact as well

Is it a coincidence? Or, is it the same problem again? It appears (by the map in the link) that this one also crashed not long after take-off.

Most incidents are going to happen at the two parts of the flight with least margin for error, take-off and landing. Even if something bad does go wrong in cruise, you are very far from the ground and glide well, you have lots of chances to fix it and not die.

So, sure, it might not be a coincidence, but "it happened near take off" is not surprising.

"It's not the fall that kills you, it's the ground" is an adage for a reason

Sure, but this plane also showed extremely erratic vertical speed readings, just as Lion Air did. The pilots appeared to be fighting the plane before requesting an emergency turn-around.

What makes you sure it is a coincidence?

I simply didn't want to jump to a conclusion, of course I can not be sure.

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