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Meh. I don't think your position makes sense. Your assessment of the estimates is basically MBA talk. They designed the helicopter for 5 flights. It is very

by ygjb 3y ago

Meh. I don't think your position makes sense. Your assessment of the estimates is basically MBA talk. They designed the helicopter for 5 flights. It is very likely the case that the requirements that a rotary wing aircraft can operate for 5 flights with minimal operator intervention, and only between missions, resulted in an helicopter that had a longer lifespan. Could they have done it cheaper? Maybe, probably, but most likely with a much higher risk of failure, and given the time, distance, and cost, and the organization doing the work, I am pretty confident that the team made the right choice.

aurareturn 3y ago
They designed the helicopter for at least 5 flights. It's just PR. Classic underpromising and overdelivering. NASA is a an entity that seeks public support and funding. Saying they over delivered by 16x is a good way to get the public, such as people in this thread, to think they're doing great.
- acdha 3y ago
  It’s more than PR: it’s recognizing that there is a massively greater cost to failure because fixing even a small problem is impossible. When you’re designing something with sufficient robustness to hit that minimum success requirement, it’s almost certain that you’ll be able to exceed it by a large margin. NASA is willing to pay more to avoid failures, and given their funding model that’s almost certainly the right call. Think about it like having to get across town after work for some reason. If it’s your buddy’s party and it’ll run all night, you might take the bus or call an Uber but it’s no big deal if you’re a few minutes late. If it’s your party, you might pay to park your car nearby or have a ride waiting for you. If it’s the meeting where you’re selling your company or announcing your presidential campaign, you might have a helicopter waiting on the roof. NASA’s stuff is all like that last case because the base costs are so high - shipping anything to another planet and waiting years to do it again, if you are given the chance, costs so much more that it makes sense to pay extra to build everything with deep safety margins just so you can say the odds of failure are comfortably low.
  - aurareturn 3y ago
    It’s underpromising and over delivering. They knew internally that it could fly 16x more. They just didn’t want to say it in a statement publicly.
    - rvnx 3y ago
      It also means costs and estimates are incorrect and a potential waste of public resources
      - acdha 3y ago
        Again, nothing is incorrect here: a margin is only waste if you’re a Walmart MBA obsessed with lowering costs. If the DOT builds a bridge with a 70 ton rating and it doesn’t collapse when an 80 ton truck drives over it, that’s not waste but rather the engineers prudently including a safety margin in each component to protect against minor defects or inconsistencies meaning that one component being slightly under spec causes the entire system to fail. NASA and aerospace as a field traditionally have a bias towards that kind of overlapping safety margins because the kinds of failures they get destroy the entire air/space-craft. If some MBA at GE cost-optimizes your dishwasher, they’re better off trimming “waste” until it dies the day after the warranty expires as long as it doesn’t fail in a way which causes you never to buy their brand again. NASA faces far more catastrophic failures and because their systems are all custom with economy of scale for large product runs and their missions by necessity have a hefty base cost so it doesn’t make sense to save $50k on rover parts when you are paying $500M to ship it to Mars.
    - coryrc 3y ago
      They knew it would last exactly 80 flights? Wow, they are good.
    - glenstein 3y ago
      Actively promising outcomes that push equipment to the brink of failure would be malpractice and the planners would deservedly be fired. These are novel and truly unprecedented space missions. There may yet be a future in which we can confidently predict outcomes at scale, but we are not there yet. Being conservative in assumptions is a virtue, and hopefully is emulated in every future mission.

by ygjb 3y ago

aurareturn 3y ago

They designed the helicopter for at least 5 flights. It's just PR. Classic underpromising and overdelivering. NASA is a an entity that seeks public support and funding. Saying they over delivered by 16x is a good way to get the public, such as people in this thread, to think they're doing great.

acdha 3y ago
It’s more than PR: it’s recognizing that there is a massively greater cost to failure because fixing even a small problem is impossible. When you’re designing something with sufficient robustness to hit that minimum success requirement, it’s almost certain that you’ll be able to exceed it by a large margin. NASA is willing to pay more to avoid failures, and given their funding model that’s almost certainly the right call. Think about it like having to get across town after work for some reason. If it’s your buddy’s party and it’ll run all night, you might take the bus or call an Uber but it’s no big deal if you’re a few minutes late. If it’s your party, you might pay to park your car nearby or have a ride waiting for you. If it’s the meeting where you’re selling your company or announcing your presidential campaign, you might have a helicopter waiting on the roof. NASA’s stuff is all like that last case because the base costs are so high - shipping anything to another planet and waiting years to do it again, if you are given the chance, costs so much more that it makes sense to pay extra to build everything with deep safety margins just so you can say the odds of failure are comfortably low.
- aurareturn 3y ago
  It’s underpromising and over delivering. They knew internally that it could fly 16x more. They just didn’t want to say it in a statement publicly.
  - rvnx 3y ago
    It also means costs and estimates are incorrect and a potential waste of public resources
    - acdha 3y ago
      Again, nothing is incorrect here: a margin is only waste if you’re a Walmart MBA obsessed with lowering costs. If the DOT builds a bridge with a 70 ton rating and it doesn’t collapse when an 80 ton truck drives over it, that’s not waste but rather the engineers prudently including a safety margin in each component to protect against minor defects or inconsistencies meaning that one component being slightly under spec causes the entire system to fail. NASA and aerospace as a field traditionally have a bias towards that kind of overlapping safety margins because the kinds of failures they get destroy the entire air/space-craft. If some MBA at GE cost-optimizes your dishwasher, they’re better off trimming “waste” until it dies the day after the warranty expires as long as it doesn’t fail in a way which causes you never to buy their brand again. NASA faces far more catastrophic failures and because their systems are all custom with economy of scale for large product runs and their missions by necessity have a hefty base cost so it doesn’t make sense to save $50k on rover parts when you are paying $500M to ship it to Mars.
  - coryrc 3y ago
    They knew it would last exactly 80 flights? Wow, they are good.
  - glenstein 3y ago
    Actively promising outcomes that push equipment to the brink of failure would be malpractice and the planners would deservedly be fired. These are novel and truly unprecedented space missions. There may yet be a future in which we can confidently predict outcomes at scale, but we are not there yet. Being conservative in assumptions is a virtue, and hopefully is emulated in every future mission.