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> “Boss,” he says to me, “This fucker ain’t gonna work. Look at this thing. It’s short, it’s too close to the wheels, and look at this dumbass hook shoe they go

> “Boss,” he says to me, “This fucker ain’t gonna work. Look at this thing. It’s short, it’s too close to the wheels, and look at this dumbass hook shoe they got on it. If the wire don’t hit it exactly right, it’s just gonna go under the hook and you’ll bolter.” Did nobody with practical experience with arrested landings look at the arresting hook design prior to this? Obviously computer models can and do predict extremely novel solutions to existing problems, but it's worth double-checking the model when someone with practical experience says "it will never work" In this case, it seems like a simple slow-motion video of an arresting wire going under the wheels of an F-18 would have been enough to debunk the model.

icegreentea2 3y ago
> Did nobody with practical experience with arrested landings look at the arresting hook design prior to this? I mean... it's very likely that the answer is no. The last new carrier aircraft made was the Super Hornet - and that design was basically done by 1995 (the F-35 tests in question were in 2011/2012). That expertise would also be at McDonald Douglas/Boeing. Northrop Grumman has a long history of carrier aircraft development, but it would have been long dormant by that point. I'm sure there's all sorts of reasons the model's inaccuracy wasn't caught before hand, but sometimes... if you're given a model that's someone says that's been V&V'd, and it produces a result that's only a little weird, you just go with it. There are only so many things you can add extra testing onto in a project. Sometimes you choose wrong. Anyhow, consider that the model results were probably exactly what they were expecting. Remember that the designers would be honing in on the shorter tailhook. You can imagine their mental model going - "ok on legacy aircraft, we have flatter tailhooks because there's enough time for the cable to settle". And then going "ok, with a shorter tailhook, there won't be enough time to settle". And then their model comes out and say "ya, with the shorter tailhook, it won't have enough time to settle - it'll be UP IN THE AIR". Whereas reality is "ya, with the shorter tailhook, it won't have enough time to settle - it'll still be displaced DOWN".
the_af 3y ago
Random thought: this is a case where someone's intuition matched what actually happened, making us think "why don't they listen to people with common sense?". But what about the many other cases where someone with "common sense" said "this fucker ain't gonna work" but the thing worked as predicted by simulations? Surely they must have happened too.
- aidenn0 3y ago
  My point is that when models predict counterintuitive results (which they often correctly do; See e.g. Eurisco in the Traveller TCS championship, or the shape of the F-117 compared to contemporary stealth aircraft), it's worth double-checking.
MadnessASAP 3y ago
Unfortunately, my decade plus as a military aircraft tech has taught me that no, practical knowledge does not make it through the system nearly as fast as engineering "expertise".
- mechhacker 3y ago
  Same, but different industry. Lots of re-engineering of the wheel after the original designers give their warnings and recommendations, but everyone's too smart to try the simple thing that already works first.

icegreentea2 3y ago

> Did nobody with practical experience with arrested landings look at the arresting hook design prior to this? I mean... it's very likely that the answer is no. The last new carrier aircraft made was the Super Hornet - and that design was basically done by 1995 (the F-35 tests in question were in 2011/2012). That expertise would also be at McDonald Douglas/Boeing. Northrop Grumman has a long history of carrier aircraft development, but it would have been long dormant by that point. I'm sure there's all sorts of reasons the model's inaccuracy wasn't caught before hand, but sometimes... if you're given a model that's someone says that's been V&V'd, and it produces a result that's only a little weird, you just go with it. There are only so many things you can add extra testing onto in a project. Sometimes you choose wrong. Anyhow, consider that the model results were probably exactly what they were expecting. Remember that the designers would be honing in on the shorter tailhook. You can imagine their mental model going - "ok on legacy aircraft, we have flatter tailhooks because there's enough time for the cable to settle". And then going "ok, with a shorter tailhook, there won't be enough time to settle". And then their model comes out and say "ya, with the shorter tailhook, it won't have enough time to settle - it'll be UP IN THE AIR". Whereas reality is "ya, with the shorter tailhook, it won't have enough time to settle - it'll still be displaced DOWN".

the_af 3y ago

Random thought: this is a case where someone's intuition matched what actually happened, making us think "why don't they listen to people with common sense?". But what about the many other cases where someone with "common sense" said "this fucker ain't gonna work" but the thing worked as predicted by simulations? Surely they must have happened too.

aidenn0 3y ago
My point is that when models predict counterintuitive results (which they often correctly do; See e.g. Eurisco in the Traveller TCS championship, or the shape of the F-117 compared to contemporary stealth aircraft), it's worth double-checking.

MadnessASAP 3y ago

Unfortunately, my decade plus as a military aircraft tech has taught me that no, practical knowledge does not make it through the system nearly as fast as engineering "expertise".

mechhacker 3y ago
Same, but different industry. Lots of re-engineering of the wheel after the original designers give their warnings and recommendations, but everyone's too smart to try the simple thing that already works first.