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>Secondly, its not a software problem, the plane is structurally deficient. Aerospace engineer here. This is incorrect. The MAX exhibits different pitch behav

by na85 7y ago

>Secondly, its not a software problem, the plane is structurally deficient. Aerospace engineer here. This is incorrect. The MAX exhibits different pitch behavior at high angles of attack than the 737NG, which would normally require a different type certificate. MCAS was their attempt to change the handling characteristics of the MAX aircraft so that it was sufficiently similar to previous iterations of the 737. This is not the same as being "structurally deficient". The fatalities arose from a combination of ethic failures at Boeing, financial pressures from large customers, bad safety design of the MCAS system, and inadequate pilot training. Plenty of aircraft flying today exhibit nose-up pitch tendencies at high angles of attack. This is not an intractable problem; it's just not a problem that Boeing could solve while keeping to the 737NG type.

codingslave 7y ago
"This is not the same as being "structurally deficient". The fatalities arose from a combination of ethic failures at Boeing, financial pressures from large customers, bad safety design of the MCAS system, and inadequate pilot training." Boeing used a 737 airframe for economic reasons (it wwas way cheaper, didnt require pilot retraining), but needed more ground clearance for bigger engines. The 737 design cant be practically modified to have taller main landing gear. The solution was to mount to engines higher on the plane. This made the plane more unstable, so they slapped the software solution on. This "fixed" the problem, but then the plane was more complex to fly, which led to the crashes. But Boeing didn't want a plane that required retraining, so they hid the complexity of the software solutions, which led to crashes because the pilots didn't know what was going on. Sure you can say the plane was structurally fine, but this is semantics, they created a plane that was unstable because it was cheaper.
- perl4ever 7y ago
  It really annoys me when people just dismiss a point with the phrase "this is semantics". Semantics is meaning! You're ignoring the meaning of what you responded to. If you don't think the point was valid, you should give a reason.
  - codingslave 7y ago
    No I'm not, the plane is flawed. Boeing created a flawed plane to cut costs. Then they slapped software on it and called it fixed. Sure because it can fly you could call it "structurally sound", but its not. The plane is a pile of trash
    - perl4ever 7y ago
      I'm not saying you're wrong, just that it's irritating that you aren't supporting your opinion. You just state your opinion and follow it with something dismissive. Twice now. Interpreting your comments in the most charitable way, you must have reasons for your opinions that convince you, so it would contribute more to the discussion if you explained why. Nobody rejects "semantics".
  - pertymcpert 7y ago
    Yeah. If anything the phrase should be more like "syntactics". Semantics is anything but semantics.
  - richk449 7y ago
    When someone says “it’s just semantics”, they mean that the argument is only over the definition of words, not over that actual meaning.
    - perl4ever 7y ago
      That may be what they think they mean, but I can't recall an instance where that was accurate, including here. Apart from that, I don't have to like people saying "it's just semantics" if they mean the exact opposite.
- na85 7y ago
  >Sure you can say the plane was structurally fine, but this is semantics, they created a plane that was unstable because it was cheaper. In the aerospace industry, semantics matter. "Structurally deficient" implies that the aircraft structure itself (i.e. the spars, ribs, load-bearing skin, etc.) is unsafe. This is not accurate, and neither is it accurate to say the MAX is "unstable". These are terms of art with precise engineering meanings. Precision in language matters, and to dismiss it as "semantics" pre-empts any meaningful discussion of the issue at hand. It's like saying float vs char is "semantics". Those differences matter.
  - codingslave 7y ago
    Yes it is accurate. The plane crashed twice. They put engines on top of the plane that weren't made for the body.
    - na85 7y ago
      It did crash twice, but not because it is structurally unsound. And not because it is unstable. edit: Also, when you say the engines were put "on top of the plane" it makes me question if you've ever actually seen a MAX 8.
    - TylerE 7y ago
      You should stop posting about issues that you are completely clueless about. I'd point out where you're wrong, but in short: everything.
      - sokoloff 7y ago
        Well, the plane did crash twice. Everything else seems wrong though.
inferiorhuman 7y ago
Aerospace engineer here. This is incorrect. The MAX exhibits different pitch behavior at high angles of attack than the 737NG, which would normally require a different type certificate. MCAS was their attempt to change the handling characteristics of the MAX aircraft so that it was sufficiently similar to previous iterations of the 737. I'm sure the pitch up tendency is worse on the MAX, but I don't believe MCAS was added to enable the re-use of the same type certificate. The handling problems were worse than anticipated as is evidenced by the low-speed activation of MCAS. My guess is that the 737 MAX on its own wouldn't meet the handling requirements. It's been a while since the Ducommun scandal, but more recently Boeing was caught knowingly installing unsafe parts (NG/MAX slat tracks that didn't meet spec) and forging repair documentation for Air Canada. Pardon me if I take any claims that Boeing is spewing with a lump of salt. inadequate pilot training. It's hard to train for something that the manufacturer won't disclose or implement in the sims. It's even harder when the remedy (moving the trim wheels) is physically impossible.
- na85 7y ago
  >the re-use of the same type certificate. That was the demand from the airlines; that there be no training delta. For that you need to remain within the same type, or at least close enough that they're equivalent. >My guess is that the 737 MAX on its own wouldn't meet the handling requirements. Correct. >It's hard to train for something that the manufacturer won't disclose or implement in the sims. It's even harder when the remedy (moving the trim wheels) is physically impossible. Yes. The training the pilots received on the differences between the MAX and the NG (i.e. no training) was inadequate to prepare them to fly the aircraft safely.
  - inferiorhuman 7y ago
    That was the demand from the airlines; that there be no training delta. For that you need to remain within the same type, or at least close enough that they're equivalent. Those are two separate issues. There are currently four generations of 737 on the TC[1] and sim time is required between the different generations. Look at the 777 vs 777X, there are radical changes and yet the 777X is (for now) grandfathered on the 777 TC. A change requiring a new TC (or STC) is an order of magnitude more dramatic. The training mandate drove the poor design of MCAS but wasn't the reason MCAS was implemented. Even with training the MAX would never have met FAA regs without something like MCAS. The list price of the MAX is around $100 million, and Southwest wanted $1 million per aircraft if training were reqiured. If it were simply a matter of more appropriate training Boeing would've already taken the 1% haircut and moved on. American talked a good game about not wanting the MAX at all if training were required, but let's face it they'd probably rather take the training hit than wait in line for an A320 production slot. Instead Boeing shuttered the production line because the problem is simply not that easy to solve. If it were simply a matter of stick force gradient Boeing could've likely just modified the elevator feel computer. Instead Boeing went the route of moving the whole damn stabilizer, a particularly odd choice because the stabilizer moves very slowly -- slower than a reasonable person would want to prevent an impending stall. 1: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/179cdacd213801658625832a006b2e37/$FILE/A16WE_Rev_64.pdf http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeMod...
7532yahoogmail 7y ago
I tend to agree with assessment. Now, the original article to which these comments apply would have strength if it had shown where the putive losses are hidden. Still there appears to broad parallels between ethical lapses and claims that Boeing cares more about financial engineering than customer safety at the top.

by na85 7y ago

codingslave 7y ago

"This is not the same as being "structurally deficient". The fatalities arose from a combination of ethic failures at Boeing, financial pressures from large customers, bad safety design of the MCAS system, and inadequate pilot training." Boeing used a 737 airframe for economic reasons (it wwas way cheaper, didnt require pilot retraining), but needed more ground clearance for bigger engines. The 737 design cant be practically modified to have taller main landing gear. The solution was to mount to engines higher on the plane. This made the plane more unstable, so they slapped the software solution on. This "fixed" the problem, but then the plane was more complex to fly, which led to the crashes. But Boeing didn't want a plane that required retraining, so they hid the complexity of the software solutions, which led to crashes because the pilots didn't know what was going on. Sure you can say the plane was structurally fine, but this is semantics, they created a plane that was unstable because it was cheaper.

perl4ever 7y ago
It really annoys me when people just dismiss a point with the phrase "this is semantics". Semantics is meaning! You're ignoring the meaning of what you responded to. If you don't think the point was valid, you should give a reason.
- codingslave 7y ago
  No I'm not, the plane is flawed. Boeing created a flawed plane to cut costs. Then they slapped software on it and called it fixed. Sure because it can fly you could call it "structurally sound", but its not. The plane is a pile of trash
  - perl4ever 7y ago
    I'm not saying you're wrong, just that it's irritating that you aren't supporting your opinion. You just state your opinion and follow it with something dismissive. Twice now. Interpreting your comments in the most charitable way, you must have reasons for your opinions that convince you, so it would contribute more to the discussion if you explained why. Nobody rejects "semantics".
- pertymcpert 7y ago
  Yeah. If anything the phrase should be more like "syntactics". Semantics is anything but semantics.
- richk449 7y ago
  When someone says “it’s just semantics”, they mean that the argument is only over the definition of words, not over that actual meaning.
  - perl4ever 7y ago
    That may be what they think they mean, but I can't recall an instance where that was accurate, including here. Apart from that, I don't have to like people saying "it's just semantics" if they mean the exact opposite.
na85 7y ago
>Sure you can say the plane was structurally fine, but this is semantics, they created a plane that was unstable because it was cheaper. In the aerospace industry, semantics matter. "Structurally deficient" implies that the aircraft structure itself (i.e. the spars, ribs, load-bearing skin, etc.) is unsafe. This is not accurate, and neither is it accurate to say the MAX is "unstable". These are terms of art with precise engineering meanings. Precision in language matters, and to dismiss it as "semantics" pre-empts any meaningful discussion of the issue at hand. It's like saying float vs char is "semantics". Those differences matter.
- codingslave 7y ago
  Yes it is accurate. The plane crashed twice. They put engines on top of the plane that weren't made for the body.
  - na85 7y ago
    It did crash twice, but not because it is structurally unsound. And not because it is unstable. edit: Also, when you say the engines were put "on top of the plane" it makes me question if you've ever actually seen a MAX 8.
  - TylerE 7y ago
    You should stop posting about issues that you are completely clueless about. I'd point out where you're wrong, but in short: everything.
    - sokoloff 7y ago
      Well, the plane did crash twice. Everything else seems wrong though.

inferiorhuman 7y ago

Aerospace engineer here. This is incorrect. The MAX exhibits different pitch behavior at high angles of attack than the 737NG, which would normally require a different type certificate. MCAS was their attempt to change the handling characteristics of the MAX aircraft so that it was sufficiently similar to previous iterations of the 737. I'm sure the pitch up tendency is worse on the MAX, but I don't believe MCAS was added to enable the re-use of the same type certificate. The handling problems were worse than anticipated as is evidenced by the low-speed activation of MCAS. My guess is that the 737 MAX on its own wouldn't meet the handling requirements. It's been a while since the Ducommun scandal, but more recently Boeing was caught knowingly installing unsafe parts (NG/MAX slat tracks that didn't meet spec) and forging repair documentation for Air Canada. Pardon me if I take any claims that Boeing is spewing with a lump of salt. inadequate pilot training. It's hard to train for something that the manufacturer won't disclose or implement in the sims. It's even harder when the remedy (moving the trim wheels) is physically impossible.

na85 7y ago
>the re-use of the same type certificate. That was the demand from the airlines; that there be no training delta. For that you need to remain within the same type, or at least close enough that they're equivalent. >My guess is that the 737 MAX on its own wouldn't meet the handling requirements. Correct. >It's hard to train for something that the manufacturer won't disclose or implement in the sims. It's even harder when the remedy (moving the trim wheels) is physically impossible. Yes. The training the pilots received on the differences between the MAX and the NG (i.e. no training) was inadequate to prepare them to fly the aircraft safely.
- inferiorhuman 7y ago
  That was the demand from the airlines; that there be no training delta. For that you need to remain within the same type, or at least close enough that they're equivalent. Those are two separate issues. There are currently four generations of 737 on the TC[1] and sim time is required between the different generations. Look at the 777 vs 777X, there are radical changes and yet the 777X is (for now) grandfathered on the 777 TC. A change requiring a new TC (or STC) is an order of magnitude more dramatic. The training mandate drove the poor design of MCAS but wasn't the reason MCAS was implemented. Even with training the MAX would never have met FAA regs without something like MCAS. The list price of the MAX is around $100 million, and Southwest wanted $1 million per aircraft if training were reqiured. If it were simply a matter of more appropriate training Boeing would've already taken the 1% haircut and moved on. American talked a good game about not wanting the MAX at all if training were required, but let's face it they'd probably rather take the training hit than wait in line for an A320 production slot. Instead Boeing shuttered the production line because the problem is simply not that easy to solve. If it were simply a matter of stick force gradient Boeing could've likely just modified the elevator feel computer. Instead Boeing went the route of moving the whole damn stabilizer, a particularly odd choice because the stabilizer moves very slowly -- slower than a reasonable person would want to prevent an impending stall. 1: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/179cdacd213801658625832a006b2e37/$FILE/A16WE_Rev_64.pdf http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeMod...

7532yahoogmail 7y ago

I tend to agree with assessment. Now, the original article to which these comments apply would have strength if it had shown where the putive losses are hidden. Still there appears to broad parallels between ethical lapses and claims that Boeing cares more about financial engineering than customer safety at the top.