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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

#151

Post by mathogre »

That's bullshit. The MAX aircraft are not the same as the earlier 737 line. These should be completely certified as new aircraft, and my guess is they would fail real certification. The required "design changes" are nothing. Not only would I not want to fly on one of the MAX aircraft, I wouldn't want to live underneath a procedure - departure, airway, approach - used by a MAX.

Go for it. Let them fly. 'Boeing has built so many, we can't let them fail!' Uh huh. Political Sunk Cost.

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

#152

Post by burfog »

henryfjordan wrote: post #7
zaroth wrote: post #3

https://www.faa.gov/news/media/attachments/19_035n-R3-8-3-20... > "To address the unsafe condition, the FAA proposes to require four design changes: (1) installing updated flight control software (with new control laws) for the FCC operational program software (OPS), (2) installing updated MDS display processing computer (DPC) software to generate an AOA disagree alert, (3) revising certain AFM flightcrew operating p…

> disable MCAS for the remainder of the flight. My understanding is that the MCAS or something equivalent is necessary on the 737 MAX because the engines sit lower than they really should and the forward propulsion creates torque that raises the nose of the plane. Something needs to counteract that force. If the MCAS is disabled, is the pilot able to trim the airplane manually similar to how MCAS works? Or will they…

No, the engines are not low. They can't be, because the wing is low and the landing gear is short.

The engines are wider than the old ones. They are also much further forward, in order to avoid being low enough to hit the pavement. (part of the engine is higher up than the underside of the wing) These differences mean that the engines can act somewhat like canards, generating lift near the front of the aircraft. The engines themselves, even when not powered, generate lift.

The lift increases as the nose rises. This means that raising the nose becomes easier the more the pilot raises the nose, which is a hazardous way for controls to operate.

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

#153

Post by CaptainZapp »

fsckboy wrote: post #143
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.

Yours is not a good argument. You can't assess this type of risk, let alone control it. Even if you are an aeronautical engineer, you won't convince me that you can assess these risks, because teams of aeronautical engineers designed this plane and did it overall very safely like they did the planes that came before it, and I'd have no reason to believe your claims. None of them assessed this level of risk as risky,…

> because teams of aeronautical engineers designed this plane and did it overall very safely

346 people and their relatives, which crashed, burned and died in two of those brand new planes within 6 month and their relatives probably beg to differ.

The history of this plane and the facts that came out after those accidents do not sound like a "very safe" design process.

Read Dominic Gates' reporting (for which he got a Pulitzer) to inform yourself about some of the nastier aspects of the design of this plane.

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

#154

Post by CaptainZapp »

TylerE wrote: post #78
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.

How are you getting to the airport? However the method, it's far more likely to injure you than flying on a 737 MAX.

Only in America, where a car is often your only option to get to the airport.

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

#155

Post by CaptainZapp »

tw04 wrote: post #142
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…

>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. Something tells me their competitors (who aren't flying 737 Max) are going to advertise that they don't and the ones who are refusing to tell you what plane you're flying on are going to lose a ton of business. Delta is already a dominant player, making a move like you've…

> Delta is already a dominant player

Slightly off-topic, but...

They get additional bonus points from me for stringent enforcement of mask wearing policy.

If you don't wear a mask you don't board the plane. If you take it off during taxiing or during the flight and refuse to wear it they kick you off the plane and ban you from flying with them.

If I would have to fly any US carrier I would chose theme whenever possible.

Edited to add: They kick you off while still on the ground.

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

#156

Post by ramraj07 »

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…

Simple, people will just choose airlines that don't have too many max aircraft

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

#157

Post by WalterBright »

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…

> would anyone choose to book a trip on one of these new Boeing aircraft rather than anything else?

I would - and I'm a former Boeing flight controls engineer, so my opinion is not limited to whatever I read from journalists who get about 75% of things wrong whenever they write about aviation.

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

#158

Post by apendleton »

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…

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 happens to be an hour away from me by whatever mode of transport I happen to be using (so, either New York or someplace outside of Baltimore) and I want to know which is safer"... but I can't for the life of me fathom why the second is a tradeoff anyone would actually be forced to consider. People generally travel with the objective of getting from some specific place to some other specific place.

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

#159

Post by WalterBright »

zucker42 wrote: post #48
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.

Obviously you'd choose the safer plane if it's equally convenient. But if the absolute risk is low and there's no other plane at the same time, or the alternatives cost 2x as much, it's reasonable to be willing to fly on a more dangerous plane.

> safer airplane

Every airplane is slightly different in its risks. Sort of like every car is also slightly different.

The MAX has been so thoroughly gone over, it's likely the safest airliner in the sky.

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

#160

Post by WalterBright »

thatswrong0 wrote: post #150
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.

> 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 be needed to overcome any stabilizer nose down trim already applied. Electric stabilizer trim can be used to neutralize control column pitch forces before moving the STAB TRIM CUTOUT switches to CUTOUT. Manual stabilizer trim can be used before and after the STAB TRIM CUTOUT switches are moved to CUTOUT."

https://theaircurrent.com/wp-content/uploads/2018/11/B737-MA...

Why they didn't read, remember, or follow the EAD instructions is anybody's guess, as I've never heard of any investigation into that aspect.

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