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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

#61

Post by drstewart »

dimitrios1 wrote: post #30
shajznnckfke wrote: post #17

Earlier quoted context omitted.

Even though this model has big design flaws and a relatively bad safety record, the absolute level of risk is still pretty low. I knowingly expose myself to larger risks in my day-to-day life. So I won’t lose any sleep over booking a flight on this type of plane.

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 absolutely love to see a log of food you've eaten over the past few weeks.

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

#62

Post by makomk »

skykooler wrote: post #53
xvf22 wrote: post #46

Earlier quoted context omitted.

Given that the 737 isn't fly by wire the forces needed to operate the controls is something critical that a home sim isn't going to be able to model.

There are force feedback joysticks, though I don't know whether something like MS Flight Simulator supports that.

It'd take a pretty fancy home force feedback system to be able to simulate forces in the multiple-pound range, which I think is what it'd take to give an accurate simulation.

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

#63

Post by Const-me »

xvf22 wrote: post #46
jmann99999 wrote: post #34

Given the upcoming Microsoft Flight Simulator 2020 release, I wish it could provide us non-commercial flyers with a simulation of the flight controls under the specific events that cause failure in the Max 737. I realize the subject isn't something a corporation would touch or code for, nor do they have a 737 in the lineup for 2020, but it would provide me with better understanding of the problem.

Given that the 737 isn't fly by wire the forces needed to operate the controls is something critical that a home sim isn't going to be able to model.

These forces were due to a design issue. Despite 737 ain't fly by wire it still has hydraulics, I think even 2 independent ones for redundancy.

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

#64

Post by random314 »

shajznnckfke wrote: post #17
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…

Even though this model has big design flaws and a relatively bad safety record, the absolute level of risk is still pretty low. I knowingly expose myself to larger risks in my day-to-day life. So I won’t lose any sleep over booking a flight on this type of plane.

You will have to quantify your argument

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

#65

Post by airstrike »

drstewart wrote: post #61
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 absolutely love to see a log of food you've eaten over the past few weeks.

I may be in the minority, but I don't really crave Boeing 737 MAX rides...

The parent also wasn't arguing they always make wise choices, just that the grandparent's choice was unwise, which you haven't proved to be false.

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

#66

Post by imglorp »

kevin_thibedeau wrote: post #4

They need to implement triple redundant AOA indicators. It's obscene that these failure modes are even possible much less approved. Knowing there is a disagreement just lets you know you are close to being fucked.

Triple is not needed, just double with a redundant "disagree" alarm.

Once the pilot knows there's one bad AOA, they can lock out the bad one as an input to the autopilot/MCAS, or hand fly without automation. Of course this is all a bunch of new software and training though.

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

#67

Post by random314 »

drstewart wrote: post #61
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 absolutely love to see a log of food you've eaten over the past few weeks.

I can't see any calculations by which a typical diet over a few weeks is riskier than a 737 MAX. Have you built such a risk model?

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

#68

Post by himinlomax »

linuxftw wrote: post #36
rootusrootus wrote: post #18

Earlier quoted context omitted.

> It must feels like an entirely different aircraft No, if MCAS is disabled then the vast majority of the time it will fly just like normal. MCAS is only there to adjust flying characteristics when the wing is at a high angle of attack.

> only there to adjust flying characteristics when the wing is at a high angle of attack. No, that's a Boeing talking point. It's there to prevent the aircraft from stalling, not to 'adjust flying characteristics.' The nose pitches up during high thrust, MCAS kicks in to to counter what the pilot is doing (stick and thrust) so the plane doesn't stall.

It's not there to prevent stalling, except in as much as pitching the plane too much does eventually result in stalling; however any pilot will have pushed the stick or trimmed long beforethat. It's there to make the plane behave exactly like an older model at a high angle of attack, to counteract the engines being further forward than those models.

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

#69

Post by AnimalMuppet »

simion314 wrote: post #55
yellow_postit wrote: post #12

Earlier quoted context omitted.

Given the amount of additional scrutiny these models are getting I wouldn’t be surprised if in the long run of their lifetime they have a better safety record.

Do we know or is a reason to believe that FAA checked anything else then the MCAS and the systems related in the crashes? The MAX has probably many differences because is larger so all the new stuff should be put under the microscope since you can't trust the previous tests, measurements or decisions, Boeing guys were proud on how they mind tricked the FAA guys so FAA should now re=review everything then you can be 1…

> Do we know or is a reason to believe that FAA checked anything else then the MCAS and the systems related in the crashes?

Yes. The FAA's proposal also involves physically re-routing some cables, which is (as far as I can tell) completely non-MCAS-related.

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

#70

Post by tzs »

karmelapple wrote: post #24
henryfjordan wrote: post #7

Earlier quoted context omitted.

> 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…

This might be oversimplification, but I'll venture it and hope someone corrects me if I'm wrong: If MCAS is disabled, then the airplane will fly very differently from the 737s that everyone with an existing 737 flight rating is used to. So the plane can fly, but it'll feel different. And that sure does seem like a problem to get back safely to the ground.

MCAS only kicks in at high angle of attack with the flaps up. I believe that most flights never come near having it activate.

If it disables due to faulty sensors and the pilots are told it is disabled, most flights won't have to do anything different at that point. The plane will handle just like it normally does.

If there are flights that are supposed to have maneuvers that would trigger MCAS, pilots are going to need to be trained to avoid those maneuvers when MCAS is disabled.

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