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This might be wrong, please say if I'm wrong. I think it's easier to dislike your tech product when you work inside the company. My company produces a mission-c

This might be wrong, please say if I'm wrong. I think it's easier to dislike your tech product when you work inside the company. My company produces a mission-critical software/hardware (not something that'd kill people, but maybe harm them) and sometimes I feel very anxious since I know all the dirty dirty hacks that are put into our systems. At the end of the day, we all try to do our best, and our systems work, but it's still easier to be cautious when you know what's going behind the scenes. I don't think engineering can ever be 100% flawless, and this makes me anxious. When I'm just a consumer and not an engineer, I don't know what's going behind the scenes so this gives me a sense of security, since things seem to work.

Wowfunhappy 7y ago
> I know all the dirty dirty hacks that are put into our systems I would really hope that airplanes are a place where "dirty hacks" are unacceptable. This doesn't mean they are 100% flawless, but any known potential problem areas should be well-documented and accounted for.
- closetohome 7y ago
  I mean...they did try to fix an inherent structural design flaw with software.
  - deleted 7y ago
    [deleted]
  - Wistar 7y ago
    What is the structural flaw?
    - closetohome 7y ago
      > To handle a longer fuselage and more passengers, Boeing added larger, more powerful engines, but that required it to reposition them to maintain ground clearance. As a result, the 737 can pitch up under certain circumstances. Software, known as the Maneuvering Characteristics Augmentation System, was added to counteract that tendency. https://www.latimes.com/local/california/la-fi-boeing-max-design-20190315-story.html https://www.latimes.com/local/california/la-fi-boeing-max-de...
      - deleted 7y ago
        [deleted]
      - Wistar 7y ago
        I'd call that a change in aerodynamic or flight characteristics as compared to earlier 737s rather than a structural flaw. That might seem a picky, semantic difference, but I think that, especially with aircraft, precision language is appropriate. The aircraft is not structurally flawed or at least no structural flaws have been revealed yet. It is perhaps a design flaw but, were there no earlier 737s to which it can be compared, it'd probably just be a flight characteristic.
        magduf 7y ago
        It's a design flaw, because they're hacking an old design to have larger engines it was never designed for. If they did a clean-sheet new design, they'd never design it this way. The airframe should be retired and they should make a new one. To push this, the FAA and other certifying bodies should treat the plane as an all-new plane with no commonality with previous 737 planes, requiring all new training for pilots and a complete, new certification process for the plane, just as if it had been a clean-sheet new design.
  - staunch 7y ago
    This is a common argument that sounds reasonable but is actually based on faulty logic. Airbus pilots can't safely fly their jets at cruising speed without software (envelope protection, etc) assisting them. Air France 447 crashed, killing 228 people, when that software became disabled due to bad values from frozen sensors. The pilot flying thought the software would save him from stalling but that protection was disabled, so he crashed into the ocean. So does that mean it's a bad idea to make flight software safety critical? Probably not. It probably just means that safety critical software must be extremely good. MCAS v1 was not good software but if MCAS v2 is good software then it could might function safely for decades. And, if MCAS v1 had been good, it would have been lauded as a great solution. Engineering is about trade offs and maybe Boeing made the wrong trade off here. Ideally, you would have as little safety critical software as possible. But the fundamental concept of software correcting for flight characteristics seems entirely sound.
    - codedokode 7y ago
      But this software hack was added only to save a little amount of fuel (and money to retraint the pilots or redesign the airplane frame). Maybe it is better to have a slightly more expensive, but safer plane?
      - staunch 7y ago
        And what if a totally redesigned successor to the 737 started crashing due to a technical issue, or training issue? Second System Syndrome is a well known engineering pitfall. If the only thing wrong with the 737 MAX is that the MCAS v1 software is bad, and the MCAS v2 software is good, then the 737 MAX should fly perfectly well for decades.
    - salawat 7y ago
      If you look as far back as the 60's, there was a lot of resistance from pilots with regard to unsafe airframes where various forms of trickery were employed to cover up problematic behavior. Check the D.P. Davies Interview by the Royal Aeronautics Society with regards to the 727. Even plastering over minor behavior near stall was a controversial move due to fears of pilot's at the time of starting down a slippery slope where more and more non-regulation compliant airframes were allowed to be certified because there would be some system X that would compensate for the aircraft's bad behavior. The fear being that eventually there would be so much automation between the pilot and the end behavior of the plane, that you might as well have a dog in the cockpit to bite the pilot should he try to mess with anything; and that should anything go wrong, the pilot would be helpless due to the plane only really being airworthy to his level of skill with the automation in place. Boeing historically built planes flown by pilots. Every aspect of the planes behavior had a way for the pilot to control it. A Boeing plane would follow a pilot right out of the flight envelope, at least maintaining a 1:1 binding of pilot intent to plane output behavior. Airbus makes planes flown by automation, directed by pilots, that should that automation fail, requires a significant investment of skill maintenance to know what not to do at that time. This makes common UI for the pilot easier to implement, but comes with discipline degradation through having a computer that will largely ignore your daft commands until it suddenly has no way to measure your daftness, leaving you with a plane with a hodgepodge of reliable automation to reason through about whether or not the plane will do something daft if you order it to. History may show who won that argument, (Airbus does exist), but the fact does remain today that aircraft that one wants to certify as flying just like another aircraft (MAX flying like a 737) should actually do so. The MAX doesn't; the technological fix intended to make it so was not developed to a sufficient standard of rigor, or communicated to pilot clearly enough, to transparently account for that aerodynamic divergence. The problem is multi-faceted, yes; but the statement that the MAX suffered from a fundamental design flaw is absolutely accurate. The flaw exists aerodynamically, and in the fundamental engineering process through which it was certified. [1]https://www.aerosociety.com/news/audio-the-d-p-davies-interview-on-the-boeing-747-the-trident-vc10-one-eleven-the-boeing-727/ https://www.aerosociety.com/news/audio-the-d-p-davies-interv...
  - dsfyu404ed 7y ago
    It wasn't a structural flaw. The plane flies fine. It's a regulatory compliance flaw. It doesn't fly enough like the old one without the software. And before anyone says "hurr durr it pitches up" (or something like that) the amount it pitches up when wide open at low speed is perfectly fine from a performance standpoint but it is not similar enough to the old plane to get away without retraining pilots, hence the software.
- HeyLaughingBoy 7y ago
  There's a couple of lines of code I wrote in a medical instrument that as far as I'm concerned are a dirty hack. Now, it's a documented dirty hack -- my boss called me into his office to laugh at the comment I wrote about it being the only way to accomplish what I needed due to the stupidity of the library I had to use -- but it's a dirty hack nonetheless. The device has been performing admirably (as far as I know) for over 12 years in the field with no issues due to those few lines of code. Hacks are everywhere in engineering. As long as the analysis behind it is rigorous and the hack is provably correct, I'm OK with it.
  - Wowfunhappy 7y ago
    I realize I'm over-defining a silly term, but I'd consider that a "hack", not a dirty hack. You understood exactly what was going on and were wholly confident it would be reliable. And more to the point, you wouldn't have counted it as a mark against the product's reliability.
    - beatgammit 7y ago
      That really depends on the hack. Maybe it's fragile because it is building based on a bug, and if the library changes, the code will have to be updated. Or perhaps it's there based on bad behavior of a chip and a hardware update could change the nature of the issue (say, it relies on a particular instruction that's generated by the particular compiler in use to happen just before the code in question). A hack could be completely reliable (for the same hardware, library versions, and compiler), but still be a "dirty hack". And whether a hack is "dirty" is very subjective and, IMO, based more on how obvious the fix is (e.g. radians -> degrees -> function -> back to radians because the library documentation is wrong is less bad than a non-obvious hack like multiplying by 1 or something to avoid a compiler codegen bug because of a hardware bug). I think this horse has been thoroughly beaten, so I'll leave it here.
    - rohit33 7y ago
      While a well documented hack is OK, system, by design, shouldn't need or be built around hacks.MAX nose dive issue was a hack to counter the dive which proved fatal.
HeyLaughingBoy 7y ago
I think you're on the right track. I used to code for Medical Devices. One of the rules of thumb we used for our level of comfort with a design (apart from formal Failure Analysis, etc...) was whether or not we'd be OK with having it used on one of our kids. When you review someone's code (or mechanical design, or electronics) and you have to decide if you're OK with it being used to treat or diagnose your loved ones, it forces you to confront the immediate reality of the impact of your work. Suddenly that hack might not seem like such a good idea after all.
- neilv 7y ago
  Which is the basis of one of my arguments to anti-vaxxers: the doctors and scientists have decades of education and experience, and they take this vaccine themselves, and give it to their own children. That's the most reputable recommendation.
  - TremendousJudge 7y ago
    I don't think this is a very good argument. Anti-vaxxers care about their children very much, and therefore they DON'T vaccinate them, since they think it's bad for them. From their point of view, it's the doctors who are insane.
    - craftinator 7y ago
      I think nielv's point is that the doctors who proscribe and the scientist who design these drugs have many years of professional education and generally at least a decade of experience in their fields. They have all of that domain knowledge about the vaccine, AND they care about their kids, AND they decide to vaccinate their children. They care just as much as the anti-vaxxer parents, but they also have the medical understanding to make a reasonable decision, while the anti-vaxxer's generally don't have medical or bio-engineering degrees and experience with the vaccines.
      - DocTomoe 7y ago
maxxxxx 7y ago
I work in medical devices and I am also always surprised how many "hacks" are in the system. We haven't had any field issues so I assume we are doing pretty well. I guess most shiny things of any reasonable complexity look pretty dirty from the inside. There is just no way around it.
WalterBright 7y ago
I worked on the design of critical flight systems on the Boeing 757, and I'm particularly happy to fly on 757s. Knowing how the airplanes are designed and built made me a much less anxious flyer.
- CobrastanJorji 7y ago
  Would you buy your family a ticket on a 777 Max?
  - dredmorbius 7y ago
    The Boeing aircraft with recent notable safety issues is the 737 Max 8. Not any 777 variant. https://en.wikipedia.org/wiki/Boeing_737_MAX https://en.wikipedia.org/wiki/Boeing_737_MAX
    - WalterBright 7y ago
      Just to be pedantic, the 757 is not a variant of the 777.
  - WalterBright 7y ago
    Yes.
soverance 7y ago
That's just a more wordy way to say "ignorance is bliss". But I totally agree, and I do not think you're wrong..

Wowfunhappy 7y ago

> I know all the dirty dirty hacks that are put into our systems I would really hope that airplanes are a place where "dirty hacks" are unacceptable. This doesn't mean they are 100% flawless, but any known potential problem areas should be well-documented and accounted for.

closetohome 7y ago
I mean...they did try to fix an inherent structural design flaw with software.
- deleted 7y ago
  [deleted]
- Wistar 7y ago
  What is the structural flaw?
  - closetohome 7y ago
    > To handle a longer fuselage and more passengers, Boeing added larger, more powerful engines, but that required it to reposition them to maintain ground clearance. As a result, the 737 can pitch up under certain circumstances. Software, known as the Maneuvering Characteristics Augmentation System, was added to counteract that tendency. https://www.latimes.com/local/california/la-fi-boeing-max-design-20190315-story.html https://www.latimes.com/local/california/la-fi-boeing-max-de...
    - deleted 7y ago
      [deleted]
    - Wistar 7y ago
      I'd call that a change in aerodynamic or flight characteristics as compared to earlier 737s rather than a structural flaw. That might seem a picky, semantic difference, but I think that, especially with aircraft, precision language is appropriate. The aircraft is not structurally flawed or at least no structural flaws have been revealed yet. It is perhaps a design flaw but, were there no earlier 737s to which it can be compared, it'd probably just be a flight characteristic.
      - magduf 7y ago
        It's a design flaw, because they're hacking an old design to have larger engines it was never designed for. If they did a clean-sheet new design, they'd never design it this way. The airframe should be retired and they should make a new one. To push this, the FAA and other certifying bodies should treat the plane as an all-new plane with no commonality with previous 737 planes, requiring all new training for pilots and a complete, new certification process for the plane, just as if it had been a clean-sheet new design.
- staunch 7y ago
  This is a common argument that sounds reasonable but is actually based on faulty logic. Airbus pilots can't safely fly their jets at cruising speed without software (envelope protection, etc) assisting them. Air France 447 crashed, killing 228 people, when that software became disabled due to bad values from frozen sensors. The pilot flying thought the software would save him from stalling but that protection was disabled, so he crashed into the ocean. So does that mean it's a bad idea to make flight software safety critical? Probably not. It probably just means that safety critical software must be extremely good. MCAS v1 was not good software but if MCAS v2 is good software then it could might function safely for decades. And, if MCAS v1 had been good, it would have been lauded as a great solution. Engineering is about trade offs and maybe Boeing made the wrong trade off here. Ideally, you would have as little safety critical software as possible. But the fundamental concept of software correcting for flight characteristics seems entirely sound.
  - codedokode 7y ago
    But this software hack was added only to save a little amount of fuel (and money to retraint the pilots or redesign the airplane frame). Maybe it is better to have a slightly more expensive, but safer plane?
    - staunch 7y ago
      And what if a totally redesigned successor to the 737 started crashing due to a technical issue, or training issue? Second System Syndrome is a well known engineering pitfall. If the only thing wrong with the 737 MAX is that the MCAS v1 software is bad, and the MCAS v2 software is good, then the 737 MAX should fly perfectly well for decades.
  - salawat 7y ago
    If you look as far back as the 60's, there was a lot of resistance from pilots with regard to unsafe airframes where various forms of trickery were employed to cover up problematic behavior. Check the D.P. Davies Interview by the Royal Aeronautics Society with regards to the 727. Even plastering over minor behavior near stall was a controversial move due to fears of pilot's at the time of starting down a slippery slope where more and more non-regulation compliant airframes were allowed to be certified because there would be some system X that would compensate for the aircraft's bad behavior. The fear being that eventually there would be so much automation between the pilot and the end behavior of the plane, that you might as well have a dog in the cockpit to bite the pilot should he try to mess with anything; and that should anything go wrong, the pilot would be helpless due to the plane only really being airworthy to his level of skill with the automation in place. Boeing historically built planes flown by pilots. Every aspect of the planes behavior had a way for the pilot to control it. A Boeing plane would follow a pilot right out of the flight envelope, at least maintaining a 1:1 binding of pilot intent to plane output behavior. Airbus makes planes flown by automation, directed by pilots, that should that automation fail, requires a significant investment of skill maintenance to know what not to do at that time. This makes common UI for the pilot easier to implement, but comes with discipline degradation through having a computer that will largely ignore your daft commands until it suddenly has no way to measure your daftness, leaving you with a plane with a hodgepodge of reliable automation to reason through about whether or not the plane will do something daft if you order it to. History may show who won that argument, (Airbus does exist), but the fact does remain today that aircraft that one wants to certify as flying just like another aircraft (MAX flying like a 737) should actually do so. The MAX doesn't; the technological fix intended to make it so was not developed to a sufficient standard of rigor, or communicated to pilot clearly enough, to transparently account for that aerodynamic divergence. The problem is multi-faceted, yes; but the statement that the MAX suffered from a fundamental design flaw is absolutely accurate. The flaw exists aerodynamically, and in the fundamental engineering process through which it was certified. [1]https://www.aerosociety.com/news/audio-the-d-p-davies-interview-on-the-boeing-747-the-trident-vc10-one-eleven-the-boeing-727/ https://www.aerosociety.com/news/audio-the-d-p-davies-interv...
- dsfyu404ed 7y ago
  It wasn't a structural flaw. The plane flies fine. It's a regulatory compliance flaw. It doesn't fly enough like the old one without the software. And before anyone says "hurr durr it pitches up" (or something like that) the amount it pitches up when wide open at low speed is perfectly fine from a performance standpoint but it is not similar enough to the old plane to get away without retraining pilots, hence the software.
HeyLaughingBoy 7y ago
There's a couple of lines of code I wrote in a medical instrument that as far as I'm concerned are a dirty hack. Now, it's a documented dirty hack -- my boss called me into his office to laugh at the comment I wrote about it being the only way to accomplish what I needed due to the stupidity of the library I had to use -- but it's a dirty hack nonetheless. The device has been performing admirably (as far as I know) for over 12 years in the field with no issues due to those few lines of code. Hacks are everywhere in engineering. As long as the analysis behind it is rigorous and the hack is provably correct, I'm OK with it.
- Wowfunhappy 7y ago
  I realize I'm over-defining a silly term, but I'd consider that a "hack", not a dirty hack. You understood exactly what was going on and were wholly confident it would be reliable. And more to the point, you wouldn't have counted it as a mark against the product's reliability.
  - beatgammit 7y ago
    That really depends on the hack. Maybe it's fragile because it is building based on a bug, and if the library changes, the code will have to be updated. Or perhaps it's there based on bad behavior of a chip and a hardware update could change the nature of the issue (say, it relies on a particular instruction that's generated by the particular compiler in use to happen just before the code in question). A hack could be completely reliable (for the same hardware, library versions, and compiler), but still be a "dirty hack". And whether a hack is "dirty" is very subjective and, IMO, based more on how obvious the fix is (e.g. radians -> degrees -> function -> back to radians because the library documentation is wrong is less bad than a non-obvious hack like multiplying by 1 or something to avoid a compiler codegen bug because of a hardware bug). I think this horse has been thoroughly beaten, so I'll leave it here.
  - rohit33 7y ago
    While a well documented hack is OK, system, by design, shouldn't need or be built around hacks.MAX nose dive issue was a hack to counter the dive which proved fatal.

HeyLaughingBoy 7y ago

I think you're on the right track. I used to code for Medical Devices. One of the rules of thumb we used for our level of comfort with a design (apart from formal Failure Analysis, etc...) was whether or not we'd be OK with having it used on one of our kids. When you review someone's code (or mechanical design, or electronics) and you have to decide if you're OK with it being used to treat or diagnose your loved ones, it forces you to confront the immediate reality of the impact of your work. Suddenly that hack might not seem like such a good idea after all.

neilv 7y ago
Which is the basis of one of my arguments to anti-vaxxers: the doctors and scientists have decades of education and experience, and they take this vaccine themselves, and give it to their own children. That's the most reputable recommendation.
- TremendousJudge 7y ago
  I don't think this is a very good argument. Anti-vaxxers care about their children very much, and therefore they DON'T vaccinate them, since they think it's bad for them. From their point of view, it's the doctors who are insane.
  - craftinator 7y ago
    I think nielv's point is that the doctors who proscribe and the scientist who design these drugs have many years of professional education and generally at least a decade of experience in their fields. They have all of that domain knowledge about the vaccine, AND they care about their kids, AND they decide to vaccinate their children. They care just as much as the anti-vaxxer parents, but they also have the medical understanding to make a reasonable decision, while the anti-vaxxer's generally don't have medical or bio-engineering degrees and experience with the vaccines.
    - DocTomoe 7y ago

maxxxxx 7y ago

I work in medical devices and I am also always surprised how many "hacks" are in the system. We haven't had any field issues so I assume we are doing pretty well. I guess most shiny things of any reasonable complexity look pretty dirty from the inside. There is just no way around it.

WalterBright 7y ago

I worked on the design of critical flight systems on the Boeing 757, and I'm particularly happy to fly on 757s. Knowing how the airplanes are designed and built made me a much less anxious flyer.

CobrastanJorji 7y ago
Would you buy your family a ticket on a 777 Max?
- dredmorbius 7y ago
  The Boeing aircraft with recent notable safety issues is the 737 Max 8. Not any 777 variant. https://en.wikipedia.org/wiki/Boeing_737_MAX https://en.wikipedia.org/wiki/Boeing_737_MAX
  - WalterBright 7y ago
    Just to be pedantic, the 757 is not a variant of the 777.
- WalterBright 7y ago
  Yes.

soverance 7y ago

That's just a more wordy way to say "ignorance is bliss". But I totally agree, and I do not think you're wrong..