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Comment by laydn | Hacker News Reader

This entire industry is (was?) based on "safety-first" principle. After two very similar incidents, I find it incomprehensible that airlines are still flying with this aircraft. Two catastrophic incidents within a few months for a new aircraft is simply unprecedented.

At the very least, MAX8 fleet should be grounded for a few days, just until the FDR/CVR of ET302 are analyzed. They've already found the boxes, so it should be only a few days before we have a preliminary report.

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All indications are they already know what happened. This is entirely a result of Boeing trying to get this plane pushed through without requiring additional training. Problem being... they changed the behavior so that pilots flying it like a regular old 737 don't know what's happening.

I hope there is a lawsuit of some sort so that boeing doesn't pull this ever again.

The fact that a critical software (MCAS) is installed and not disclosed to the pilots is significant blow to their reputation.

Thats because its an USA company. You don't see it coming up in news, you don't see any lawsuits from other countries, and they will keep covering the real issue as long as they like. There have been incidents in past when corporations have leveraged USA influence to punish countries that have tried bringing airlines companies to justice(like when Indonesian airlines were barred from entering USA airspace because of them blacklisting a American airline). Had it been another company whole Airline would have been grounded and news channels would have been all over it.

The comet's first paying flight was May 2nd 1952, there were hull losses in Oct 1952 (no fatalities), March 1953 and May 2nd 1953. There were then 2 more in 1954.

Yes but that was 65 years ago and the context is completely different. Planes crashed all the time back then and our safety culture and technology has changed massively. These steam locomotives[0], that look like they were built by a farmer, were ~10 years old at the time. Comet was incredibly futuristic space age technology. But with no 3D CAD or FEA simulations. No X-ray or ultrasound metallurgy. Crack propagation wasn't understood. Also, there was no CRM, no safety gadgets like stick pushers/shakers. Most pilots and airline management were WW2 ex military and a couple of planes a year is nothing compared to the 4-5 they would lose in a typical bombing sortie. I think there was an attitude of it being regrettable, but just part of life. [0] http://www.railgiants.org/union-pacific-big-boy-back-head.ht...

> These steam locomotives[0], that look like they were built by a farmer

This is a little derogatory, considering the mechanical wonder a steam locomotive was back then and still is today.

>Crack propagation wasn't understood

It was well enough understood. Square openings leading to stress risers and cracks has been known in ship building since at leas the 1940s.

Yet it was put into planes. So either it wasn't really understood in the context, or no one that knew about it was advising on the design of aircrafts.

The corners on the windows did have a fairly large radius. Just not large enough (hindsight being 20-20). I think they knew about it and thought they had more than enough margin for safety and then never thought twice about it until aircraft started falling out of the sky.

Then it wasn't well enough understood...

I oversimplified. It was understood in specific academic circles and to an extent by leading designers, but not widely by others. The cracks actually started at a hatch on the bottom of the plane which was added to the design without going through the full engineering design QA process.

ship don't go trough a thermal and pressurization cycle at every trip however.

it wasn't square window per se as much as metal fatigue

Until it was cheap enough to manufacture with, aluminum hadn't been used in large structural components and the crack formation in aluminum is very different from steel.

With steel, if you add a large enough safety margin it will essentially never fail due to repeat stress cycles. With aluminum it doesn't matter how strong you design it, eventually cracks will form and it will fail.

What are you talking about?

1) is "built by farmers" supposed to be derogatory, because farmers are often very mechanically inclined and make the best of what they have.

2) Steam engines are very capable, complex beasts. The big boy that you linked to is one of the largest and more complex one's ever built. Diesel engines wouldn't pack this much power in a single unit for multiple decades to come.

2a) you do realize that basically every electrical power plant sans hydro and photovoltaic are basically steam (turbine) engines and these work horses of old sharer large amounts of experience to the power plants of today?

3) The safety culture of the railways has always been important, almost as much as it is for air travel. (Yes, there have been some high profile accidents recently, but comparing fatalities to total trips is still favourable.)

It appears to me you saw a picture of something that didn't look "modern" and thought that it was primitive. It also appears that you thought primitive means simple. Those are never good assumptions.

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