4 ms·

How robust are these to random floating logs? They’re quite common here in the Salish Sea and have been cited as the reason that the Boeing hydrofoil project ne

How robust are these to random floating logs? They’re quite common here in the Salish Sea and have been cited as the reason that the Boeing hydrofoil project never really took off.

garciasn 3y ago
Hitting debris or the bottom while on foils is NOT recommended and can be catastrophic to the boat and its passengers. Hydrofoils haven't taken off because of the above and, primarily, the high operation, maintenance, and build costs. Historically, these just have not been more economical than their traditional counterparts. Being that this particular company is not focused on those parts of this and are solely focused on the technology being green, my guess is they are ignoring the operation, maintenance, and build costs and hoping that they can be all hand-wavey about that part--which probably will not pay off for them.
- roflyear 3y ago
  My understanding was that, similar to a sail on a boat, you really want to be able to "trim" your foil, which is really complicated. You can have a good "average" foil but it will really be great in most conditions.
  - jesperwe 3y ago
    Candela foils are dynamically trimmed under computer control.
- I_Am_Nous 3y ago
  From an engineering perspective the hull would have to be strong enough to support all the weight of the vessel on the foil mounts. I imagine this is not a trivial problem to solve and the vessel would have to be purpose designed for foils, so little retrofitting may be possible on existing vessels.
  - flybrand 3y ago
    I clipped a granite plinth Efoiling - your ride comes to a very abrupt halt. Thankfully the board was fine and the carbon fiber wing had just minor scuffing.
    - gilbertbw 3y ago
      I would be concerned that the carbon fibre has been significantly weakened by the impact. https://www.resinlibrary.com/knowledge/article/can-carbon-fibre-be-repaired/ https://www.resinlibrary.com/knowledge/article/can-carbon-fi... > Since fibre strength significantly exceeds that of the matrix (epoxy), damage usually occurs in the matrix before the fibres for laminate composites. In some instances, this is relatively easy to detect; snapped fibres protruding from the object’s surface. Yet more microscopic damage – something which can spread through the object – is harder to detect even though it can significantly reduce the mechanical properties of the composite.
      - flybrand 3y ago
        I’m concerned, but it’s a hobby where the penalty for failure is getting wet.
    - I_Am_Nous 3y ago
      That looks like a lot of fun, kind of like a OneWheel on water, but safer because water lands a lot softer than the hard ground does!
  - bagels 3y ago
    Weight of the boat + dynamic loads.
    - I_Am_Nous 3y ago
      Great point lol it's not like the carried load will be the same all the time and I didn't even consider that :)
- thriftwy 3y ago
  Boats are, in general, an unpopular way to carry passengers these days, and of those, hydrofoils have a significant share. It's debatable whereas anything ense has "taken off" if hydrofoils didn't.
  - beachy 3y ago
    There must be thousands or tens of thousands of ferries around the world, yet hydrofoil ferries are as rare as rocking horse shit, so I don't think this is correct.
    - thriftwy 3y ago
      I know only a couple of non-ferry scheduled passenger boats (no car deck) and half of these are easily hydrofoils. I guess that depends on the region, though.
kitd 3y ago
> the Boeing hydrofoil project never really took off. badoom tish Don't tell us, you're here all week? ;)
devindotcom 3y ago
I actually rode a C-8 around Elliott Bay and asked about this since as you say there's lots of logs, or deadheads as my grandpa called them. They said it's not optimal but the logs can be detected and accounted for, and the fins are super strong to impacts from the front. Better to avoid, of course, but they said it would be OK. It just whacks them out of the way basically.
- ttul 3y ago
  Many logs in the Salish Sea are actually enormous tree trunks complete with root systems…
- specialist 3y ago
  My neighbor worked on those hydrofoils. He once told me the foil's spars (?) were made of titanium, which could handle (eg obliterate) sizeable logs. 10" diameter? Edit: Just asked neighbor. He remembers the Pegasus was rated for 18" logs. https://en.wikipedia.org/wiki/USS_Pegasus_(PHM-1) https://en.wikipedia.org/wiki/USS_Pegasus_(PHM-1) Also, the intended top speed proved infeasible, because the foils (wings) would cavitate at high speed, reducing lift. He also worked on Boeing 929 jetfoils. Additional color to the story was a collision with a whale. Gruesome. Big PR mess too. So now no more hydrofoils on the Salish Sea.
gosub100 3y ago
would be a perfect application for sonar, wouldn't it?

How robust are these to random floating logs? They’re quite common here in the Salish Sea and have been cited as the reason that the Boeing hydrofoil project never really took off.

garciasn 3y ago

Hitting debris or the bottom while on foils is NOT recommended and can be catastrophic to the boat and its passengers. Hydrofoils haven't taken off because of the above and, primarily, the high operation, maintenance, and build costs. Historically, these just have not been more economical than their traditional counterparts. Being that this particular company is not focused on those parts of this and are solely focused on the technology being green, my guess is they are ignoring the operation, maintenance, and build costs and hoping that they can be all hand-wavey about that part--which probably will not pay off for them.

roflyear 3y ago
My understanding was that, similar to a sail on a boat, you really want to be able to "trim" your foil, which is really complicated. You can have a good "average" foil but it will really be great in most conditions.
- jesperwe 3y ago
  Candela foils are dynamically trimmed under computer control.
I_Am_Nous 3y ago
From an engineering perspective the hull would have to be strong enough to support all the weight of the vessel on the foil mounts. I imagine this is not a trivial problem to solve and the vessel would have to be purpose designed for foils, so little retrofitting may be possible on existing vessels.
- flybrand 3y ago
  I clipped a granite plinth Efoiling - your ride comes to a very abrupt halt. Thankfully the board was fine and the carbon fiber wing had just minor scuffing.
  - gilbertbw 3y ago
    I would be concerned that the carbon fibre has been significantly weakened by the impact. https://www.resinlibrary.com/knowledge/article/can-carbon-fibre-be-repaired/ https://www.resinlibrary.com/knowledge/article/can-carbon-fi... > Since fibre strength significantly exceeds that of the matrix (epoxy), damage usually occurs in the matrix before the fibres for laminate composites. In some instances, this is relatively easy to detect; snapped fibres protruding from the object’s surface. Yet more microscopic damage – something which can spread through the object – is harder to detect even though it can significantly reduce the mechanical properties of the composite.
    - flybrand 3y ago
      I’m concerned, but it’s a hobby where the penalty for failure is getting wet.
  - I_Am_Nous 3y ago
    That looks like a lot of fun, kind of like a OneWheel on water, but safer because water lands a lot softer than the hard ground does!
- bagels 3y ago
  Weight of the boat + dynamic loads.
  - I_Am_Nous 3y ago
    Great point lol it's not like the carried load will be the same all the time and I didn't even consider that :)
thriftwy 3y ago
Boats are, in general, an unpopular way to carry passengers these days, and of those, hydrofoils have a significant share. It's debatable whereas anything ense has "taken off" if hydrofoils didn't.
- beachy 3y ago
  There must be thousands or tens of thousands of ferries around the world, yet hydrofoil ferries are as rare as rocking horse shit, so I don't think this is correct.
  - thriftwy 3y ago
    I know only a couple of non-ferry scheduled passenger boats (no car deck) and half of these are easily hydrofoils. I guess that depends on the region, though.

kitd 3y ago

> the Boeing hydrofoil project never really took off. badoom tish Don't tell us, you're here all week? ;)

devindotcom 3y ago

I actually rode a C-8 around Elliott Bay and asked about this since as you say there's lots of logs, or deadheads as my grandpa called them. They said it's not optimal but the logs can be detected and accounted for, and the fins are super strong to impacts from the front. Better to avoid, of course, but they said it would be OK. It just whacks them out of the way basically.

ttul 3y ago
Many logs in the Salish Sea are actually enormous tree trunks complete with root systems…
specialist 3y ago
My neighbor worked on those hydrofoils. He once told me the foil's spars (?) were made of titanium, which could handle (eg obliterate) sizeable logs. 10" diameter? Edit: Just asked neighbor. He remembers the Pegasus was rated for 18" logs. https://en.wikipedia.org/wiki/USS_Pegasus_(PHM-1) https://en.wikipedia.org/wiki/USS_Pegasus_(PHM-1) Also, the intended top speed proved infeasible, because the foils (wings) would cavitate at high speed, reducing lift. He also worked on Boeing 929 jetfoils. Additional color to the story was a collision with a whale. Gruesome. Big PR mess too. So now no more hydrofoils on the Salish Sea.

gosub100 3y ago

would be a perfect application for sonar, wouldn't it?