Canada grounds Boeing 737 Max 8 • Hacker News Board

Re: Canada grounds Boeing 737 Max 8

#291

Post by nopriorarrests » Wed, Mar 13, 2019, 7:51 PM UTC

linuxftw wrote: post #233

yingw787 wrote: post #157

And then there was one. I do wonder if we can halt and revert the deterioration of the Civil Service before the whole "civilization is two days worth of food and water" scenario arrives. If it does, I think it'll be through something that generates a disproportionate amount of fear and anxiety in people resulting in a significant impact to the economy in a sector where middle to upper class folks are heavily exposed…

The problem, I think, is there's no established protocol in this situation. Congress leaves entirely too much decision making up to the executive branch. How hard is it to write a law such as "If the same (public) commercial model plane crashes with fatalities more than once in an 18 month period, that model plane shall be grounded indefinitely until a root cause is established and mitigated" This would have some int…

>airlines would value diversity in the fleets

aka much more money to certify pilot crew, aka more expensive fares, aka less experience for any given pilot with some particular aircraft type.

Re: Canada grounds Boeing 737 Max 8

#292

Post by mikeash » Wed, Mar 13, 2019, 7:54 PM UTC

rootusrootus wrote: post #215

mikeash wrote: post #155

Earlier quoted context omitted.

Those numbers are for the UK in the 1990s. Commercial aviation is much safer today. The fatality rate per journey for US airlines over the last ten years is approximately 0.14 per billion journeys, several hundred times better than the number from your link. (Roughly 700 million journeys per year on average, one fatality during that period.) Cars have gotten safer too, but not nearly as much.

Is there a point at which the statistics are too muddy to be useful? We have had 1 fatality in the last ten years, but in the last 10 years, 1 month, and 1 day we have had 51 fatalities.

Definitely! If you take the fatalities for the last ten years and convert that to a risk estimate, the result will have gigantic error bars. We can be confident that the real risk is greater than zero, and it's pretty clear that it's small, but the exact number is pretty much impossible to know.

The farther back you look, the less noise you get in your data, but you also incorporate data that's less and less relevant to the current environment. Ten years seems like a decent cutoff, although it is a cutoff that happens to have had a wild swing recently.

My original point still stands if you want to take the data back a bit further: even if you include Colgan, the resulting number is way below the 117 per billion listed on that Wikipedia page.

Re: Canada grounds Boeing 737 Max 8

#293

Post by dahdum » Wed, Mar 13, 2019, 8:13 PM UTC

DavidSJ wrote: post #248

dahdum wrote: post #175

Earlier quoted context omitted.

The obsession is because the plane is new (<2 years) and there have been two fatal crashes in the past 6 months, making it by far the most dangerous plane in the skies today.

We don't know that it's the most dangerous plane in the skies today. It may be, and some of the publicly known facts are suggestive of that but not conclusive. What we know is that its accident rate is by far the worst, but on a small enough sample size that statistical anomaly cannot be ruled out.

They continued flying after the first crash for that exact reason, even though that took the accident rate an order of magnitude above the regular 737 fleet.

After the second crash, it's not worth the risk in lives to carry on before investigations are complete.

Re: Canada grounds Boeing 737 Max 8

#294

Post by aphistic » Wed, Mar 13, 2019, 8:25 PM UTC

dubbel wrote: post #44

matz1 wrote: post #35

By now its safe to assume that most pilot will know about this specific issue and know how to handle it. Well, except those Ethiopian pilot. I don't see reason to ban.

That feels like average software development mindset applied to airplanes to be honest. An airplane nosediving on sensor malfunction from time to time is not acceptable behavior that could be considered fixed by telling the pilots to disable the autopilot.

"By now it's safe to assume that most developers will know about SQL injection and know how to handle it. Well, except for all those people that still write software susceptible to them."

Re: Canada grounds Boeing 737 Max 8

#295

Post by [deleted] » Wed, Mar 13, 2019, 9:04 PM UTC

yingw787 wrote: post #261

TearsInTheRain wrote: post #241

Earlier quoted context omitted.

> So if you're concerned because Boeing's CEO is a Mar-A-Lago member with direct access to POTUS (who wants his club fees), and the Secretary of Transportation is the Senate Majority Leader's wife who is also lobbied by Boeing, and the FAA hasn't had an official administrator for two months, and the FAA can't approve safety fixes by Boeing due to government shutdowns, and aircraft manufacturing consolidation means Bo…

I think that's true to a point, but we are way past that point. We're at the point where when the government works with the private sector, a worse result is created than if the government had created it alone, or if the private sector had created it alone, where you could form a total ordering. There is no recognizable gestalt, and whole point of public/private cooperation is to generate those gestalts. Another way…

[deleted]

Re: Canada grounds Boeing 737 Max 8

#296

Post by cc439 » Wed, Mar 13, 2019, 9:18 PM UTC

dokein wrote: post #43

js2 wrote: post #20

Having read many commments on HN and elsewhere since the crash, I know I’m in the minority here when I say this but to me it seems like the US airlines and FAA are following their procedures, the same procedures that make the US airlines the safest in the world, while the rest of the world is, I don’t quite want to use the word panicking, but at least giving into pressure from people who aren’t aviation safety expert…

The level of certainty required for an action changes depending on the downside risk of action vs inaction. For example, if I am 20% certain that you have a pulmonary embolism, the correct action is to start treatment immediately; the risks of treatment are low relative the harm of waiting for further testing. The FAA and NTSB are rightly very conservative and cautious with respect to approving new designs, since the…

>The correct move here is to act even if they think the certainty is low.

What is the correct action though? The root cause of the first crash is understood to be a complete lack of training on a single aspect of the flight control system in a particular set of circumstances (one that happens to occur in the most dangerous part of the flight envelope). From what I understand about this issue, the correct action is to institute an immediate crash course (pun intended?) to train pilots on how to recognize and manage the actions of this subsystem unless further, currently unspeculated issues with the sensors and software are discovered.

>(T)he risk of grounding planes is operational inconvenience

I think you're overlooking the risks involved in adding significant pressure to flight schedulers (who have to get planes in place to make up for missed routes), maintenance crews (who have to provide more flight hours for the remaining fleet to make up for the missing planes), and pilots (who will have to fly something different than what they've recently been flying).

Think of how many opportunities for a mistake to happen would arise from changing something like the route, time, and (sometimes) vehicle used for the daily commute by every worker in a 2,000 person company. Tighter timetables, increased flight hours on the remaining fleet, and the need for pilot's to shake the rust off their skillset flying an airframe they haven't been in for a while are all significant risk factors that have played a part in the vast majority of flight accidents in the modern era of air travel.

Re: Canada grounds Boeing 737 Max 8

#297

Post by mcv » Wed, Mar 13, 2019, 9:25 PM UTC

localhost wrote: post #192

planteen wrote: post #105

Earlier quoted context omitted.

You are discounting the possibility of software controlling an aerodynamically unstable airplane safely. This has been happening for decades (see X-29, B-2, etc)

Sure, but those pilots knew they were flying that kind of aerodynamically unstable airplane ahead of time. These pilots apparently were thinking "this is just a 737".

Exactly. The plane might well be perfectly safe in properly trained hands, but it seems rather obvious by now that it doesn't fly the same as a regular 737.

Re: Canada grounds Boeing 737 Max 8

#298

Post by mcv » Wed, Mar 13, 2019, 9:27 PM UTC

sangnoir wrote: post #211

planteen wrote: post #105

Earlier quoted context omitted.

You are discounting the possibility of software controlling an aerodynamically unstable airplane safely. This has been happening for decades (see X-29, B-2, etc)

Did any of those aircraft quietly oppose the pilots authority?

I remember reading 30 years ago that the F-16 has 3 computers that vote on how to respond to user input.

Re: Canada grounds Boeing 737 Max 8

#299

Post by DavidSJ » Wed, Mar 13, 2019, 11:24 PM UTC

dahdum wrote: post #293

DavidSJ wrote: post #248

Earlier quoted context omitted.

We don't know that it's the most dangerous plane in the skies today. It may be, and some of the publicly known facts are suggestive of that but not conclusive. What we know is that its accident rate is by far the worst, but on a small enough sample size that statistical anomaly cannot be ruled out.

They continued flying after the first crash for that exact reason, even though that took the accident rate an order of magnitude above the regular 737 fleet. After the second crash, it's not worth the risk in lives to carry on before investigations are complete.

I don’t disagree. That’s a separate point though.

Re: Canada grounds Boeing 737 Max 8

#300

Post by matz1 » Wed, Mar 13, 2019, 11:39 PM UTC

magduf wrote: post #288

matz1 wrote: post #120

Earlier quoted context omitted.

If there are plenty of different plane and the cost of switching is low then yeah sure.

If you want to bet your life on something dangerous, go ahead, but don't ask others to do the same. Every major civil air authority is now grounding this plane, including the US.

It's still hardly dangerous compared to driving for example.