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U.S. FAA proposes requiring key Boeing 737 MAX design changes

reuters.com

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Re: U.S. FAA proposes requiring key Boeing 737 MAX design changes

#231

Post by Sebb767 »

caconym_ wrote: post #145
curryst wrote: post #116

Earlier quoted context omitted.

Measuring the risk of travel in terms of hours seems largely pointless, unless I'm missing something. It equates an hour bus ride with an hour plane ride, which are not interchangeable, so it makes sense that the associated risks are also not interchangeable. You could account for the additional time it takes to go on a bus to adjust for the longer duration of risk, but at that point it seems like you're just approxi…

I think it makes a lot more sense to look at risk per time, because it's basically the same thing as risk per trip, and that's what I really care about. If you tell me I can fly to Mars in a few days on a brachistochrone torchship and it's safer per mile than any other mode of transport, you may be right, and a few days cooped up in a cramped cabin might be a small price to pay for such an exotic vacation destination…

> In other words, if the odds are e.g. 1 in 10 that the trip will kill me, I don't give a shit how low the risk per mile is.

The average distance to mars is about 225 million km, so that would be one accident about every 2,2 billion km or 0.45 deaths per km, which is a bit deadlier than buses and 9 times as deadly as planes. Gives some perspective on how save planes actually are.

Re: U.S. FAA proposes requiring key Boeing 737 MAX design changes

#232

Post by WatchDog »

mitchellgoffpc wrote: post #149
WatchDog wrote: post #135

Earlier quoted context omitted.

> Even with the warning (which some US airlines paid for) Are you saying that a bad input warning was an optional(paid) extra?

Yep. The "AOA sensor disagreement" light is built into every cockpit, but it won't turn on unless the airline purchased a specific premium add-on. Boeing claims they initially didn't realize the light was bundled as an add-on, and then once they did realize, they decided it wasn't critical to the airplane's safety and just kept selling it as an add-on, which is... kind of alarming, to put it mildly. https://www.nytim…

Wow, that is remarkable.

Re: U.S. FAA proposes requiring key Boeing 737 MAX design changes

#233

Post by [deleted] »

ponker wrote: post #172
apendleton wrote: post #158

Earlier quoted context omitted.

This seems like a mode of comparison that's disconnected from actual utility. The distance comparison lets me consider a scenario like "I live in Washington, DC. I want to go to New York. I can choose to either get there by plane or car, and I want to know which is safer." This seems like a real, sensible thing to contemplate. The time comparison is "I live in Washington, DC and want to go... to wherever it is that h…

This assumes that people decide the destination before deciding the mode of transport. In my experience this isn't true, specifically with the 737 MAX. I had a 4-night trip booked with my family to Seattle from San Francisco on a 737 MAX and cancelled it when all that shit went down. Rather than driving that weekend to Seattle we drove to Yosemite because I wasn't going to drive 12 hours to Seattle. In terms of total…

[deleted]

Re: U.S. FAA proposes requiring key Boeing 737 MAX design changes

#234

Post by dimitrios1 »

CalRobert wrote: post #198
dimitrios1 wrote: post #30

Earlier quoted context omitted.

This is not a good argument. You can control this level of risk. Taking on any unnecessary risk when you don't have to is not a wise choice.

I would be very hesitant to get on a MAX, but we take unnecessary risks all the time. Getting in a car, having a beer, etc. are all activities that carry risk. Ultimately it's "will the hassle of avoiding the MAX be worth the benefit of not getting on one?" and for a lot (probably the vast majority) of people the answer is no.

Of course we take risks, but every rational human being does so in accordance to receiving some perceived value, reward, or return out of it. As it stands right now, there is literally no reason to take a MAX flight, unless you just absolutely had to get somewhere and it was the only flight available to you (unlikely).

One potential case I could see is the price of MAX flights drop low enough so that price conscious consumers decide the risk is now warranted. But that hasn't happened yet. Thus, no reason to take the unnecessary risk at this time. Future factors may change this equation.

Re: U.S. FAA proposes requiring key Boeing 737 MAX design changes

#235

Post by kd5bjo »

ummonk wrote: post #220
RandallBrown wrote: post #139

Earlier quoted context omitted.

My understanding is that the crashes were due to properly functioning (but awkward and confusing) MCAS systems. I have to imagine that any pilot flying a 737 MAX is going to have a very solid understanding of how that system works and how to tell if it's malfunctioning and avoid the same situation. Also, it was 2 crashes in 500,000 flights. It seems a little misleading to just compare it to hull losses.

Hull losses is a reasonable way to reason about relative risk of dying from spending your time on the plane. E.g. if you lived on one of the aircraft, you would have had a ~0.5% chance of dying during that time period. That's pretty terrible.

Assuming the average flight is 1 hour long, that’s a 0.5% chance of dying in 28.5 years of flight time. 0.995^138 is approximately 50%, so the expected amount of time you’d need to spend onboard to have even odds chance of dying due to hull loss is about 4000 years.

There are a lot of factors this analysis doesn’t take into account, particularly the difference in airframe fault rate over time: A new plane will have different reliability figures than a 4000-year old one.

Re: U.S. FAA proposes requiring key Boeing 737 MAX design changes

#236

Post by misanthropian00 »

WalterBright wrote: post #160
thatswrong0 wrote: post #150

Earlier quoted context omitted.

> properly functioning (but awkward and confusing) MCAS systems It had almost unlimited pitch authority, used only one (potentially faulty) AOA indicator to decide to activate, and could activate repeatedly unless purposefully deactivated. Even the way in which it was certified was extremely suspect. I'm curious as to how you think that is "properly functioning". Its initial implementation was straight up dangerous,…

The EA pilots were given an Emergency Airworthiness Directive which gave a two step process for recovering from MCAS malfunction: 1. use the electric trim switches to drive the trim to normal 2. cut off the trim system with the console cutoff switches. That's it. As simple as that. And it is NOT what the EA pilots did (they cut off the trim first). Here are the exact directions: "Initially, higher control forces may…

https://www.youtube.com/watch?v=_T5xhHzZjPQ

https://www.youtube.com/watch?v=a5P8CkVckmA

These are some links to youtube sims of the two events. It seems that the Lion Air pilot at least who of course did not know about the top secret MCAS system was trying to fight MCAS directly with electric trim and at first was successful but for some reason did not hit the cutout switches after getting back to level flight. So the Lion Air pilot used electric trim correctly but failed to use the cutoff switches and the Ethiopian pilot used the cutoff switches correctly but failed to use the electric trim long enough. Maybe the Ethiopian pilots were aware of the Lion Air flight fighting MCAS with electric trim and losing and just went directly to the runaway trim stab procedure too soon. For whatever reason both flights were also going too fast and made no attempt to slow airspeed.

Re: U.S. FAA proposes requiring key Boeing 737 MAX design changes

#237

Post by makomk »

bkor wrote: post #195
briandear wrote: post #93

Earlier quoted context omitted.

It would depend on the airline. Southwest Airlines, definitely. Some third world airline where their pilots come through pilot mills and take the controls at less than 500 hours? No way. But that is true with any airplane, not just the Max. Statistically Southwest Airlines should have had a crash, yet it was Ethiopian and Lion Air that did. Given the maintenance and pilots history of Lion Air, a crash wasn’t unexpect…

> Lion Air and Ethiopian crashes could have been prevented with better pilot actions. Boeing tried to say it was the pilots for a long time. I don't want to fly on a plane whereby you need to be an exceptional pilot to not crash the plane. Further, Lion Air requested additional pilot training. Boeing mocked them for it: https://fortune.com/2020/01/14/boeing-lion-air-extra-737-max... 2 planes crashed really quickly af…

Lion Air's request for additional training was eminently worthy of mockery from what I could tell - it would've been a lot of hassle, and so brief and cursory to be basically useless if their pilots already knew how to fly a standard 733 and completely inadequate if they didn't.

Re: U.S. FAA proposes requiring key Boeing 737 MAX design changes

#238

Post by zrobotics »

Sebb767 wrote: post #231
caconym_ wrote: post #145

Earlier quoted context omitted.

I think it makes a lot more sense to look at risk per time, because it's basically the same thing as risk per trip, and that's what I really care about. If you tell me I can fly to Mars in a few days on a brachistochrone torchship and it's safer per mile than any other mode of transport, you may be right, and a few days cooped up in a cramped cabin might be a small price to pay for such an exotic vacation destination…

> In other words, if the odds are e.g. 1 in 10 that the trip will kill me, I don't give a shit how low the risk per mile is. The average distance to mars is about 225 million km, so that would be one accident about every 2,2 billion km or 0.45 deaths per km, which is a bit deadlier than buses and 9 times as deadly as planes. Gives some perspective on how save planes actually are.

You might want to check your figures- 1 death/2.2e9 km is 4.5e-10 deaths per km. The 0.45/km figure is way out, for that to be the case there would need to be roughly 1.1billion deaths per 2.2 billion km.

Re: U.S. FAA proposes requiring key Boeing 737 MAX design changes

#239

Post by mcgoo »

Nacdor wrote: post #6

Given the option, would anyone choose to book a trip on one of these new Boeing aircraft rather than anything else? I know I wouldn't, my family wouldn't, and none of the friends or co-workers I've discussed this with would. Something tells me airlines are going to be making it even more difficult to determine which aircraft you'll be flying on when you book a ticket. As far as I know they're not required to tell you…

The MAX is also known as the 737-8200. Now that the product recognition is working against it, I think we will see the forgettable name a lot more.

At least in the US you can typically cancel a flight for free within the first 24 hours if it is booked more than seven days out, if that helps.

You are right that the airline can change the type of plane like that but it is uncommon. A much more common way to end up on a different type of plane than was booked is weather cancellation. (Personally, I don't like most of the regional jets, but by the end of the day of waiting for a 1 hour flight, I'll take anything.)

Re: U.S. FAA proposes requiring key Boeing 737 MAX design changes

#240

Post by kayfox »

AniseAbyss wrote: post #201
thatswrong0 wrote: post #83

Earlier quoted context omitted.

Yeah 2 out of 387 hull losses over 2 years is a pretty awful record. I will stick to not 737 MAX thanks.

Airliners agree with you and are changing the name of the aircraft to get away from the bad reputation this plane has. With the airline industry going through an unprecedented recession I don't think we will see a lot of new 737s being delivered thankfully.

Nobody has changed the name of the aircraft. The 8200 that Ryanair is to be flying is the 737-8 MAX 200 that Ryanair wanted.
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