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Candela P-12 taking off – Electric hydrofoiling passenger vessel [video]

330 points by JoachimS 3y ago

zknill 3y ago
The promo video has a perfectly flat body of water. I'd be interested to know what impact waves have on a hydrofoil.
- Phenomenit 3y ago
  There is another video on their channel that shows the technology in rougher weather and sea, seems to work fine.
  - roflyear 3y ago
    Which video? None of the videos I see show in rough conditions - the worst is probably "better than average" from spending time on the ocean.
    - Phenomenit 3y ago
      This one: https://www.youtube.com/watch?v=2i2Zf9WVlNY https://www.youtube.com/watch?v=2i2Zf9WVlNY
      - 0xNotMyAccount 3y ago
        All vessels have limits on the sea state they can handle, particularly small vessels. Very large vessels can generally handle much more. You can see how much more the traditional small patrol vessel is bouncing out there, my spine hurts just watching. I could see this being used for pilot vessels and harbor patrol craft, for sure.
      - Tempest1981 3y ago
        Cool, definitely a smoother ride than the adjacent boat.
      - RationalDino 3y ago
        That isn't rough. According to another comment, the Candela can handle waves of up to 1.2 meters. But about half of waves in the open ocean are 2+ meters. So this boat can't handle a normal ocean sea.
        jdmoreira 3y ago
        This is Sweden. I've lived in the east coast of Sweden for 10 years, never seen a wave and there is water everywhere. Now I'm from Portugal, so… no comparison really.
        RationalDino 3y ago
        Yes. The east coast of Sweden is the Baltic Sea, which is not an open ocean. This boat may be perfectly usable there. But that's still not a rough sea. Other than temperature, that is water that I'd be perfectly comfortable swimming in.
    - HALtheWise 3y ago
      I don't think the primary target for these boats is the ocean, they're mostly designed to operate on lakes, bays, rivers, etc
      - travoc 3y ago
        ...so places where 5 knot speed limits are often enforced to prevent wakes.
        SamBam 3y ago
        Since they barely produce wakes when they are hydrofoiling, these rules can probably be changed.
        nine_k 3y ago
        But during the transition to the hydrofoil mode and back they produce a lot of waves and wake; seen this many times firsthand.
        sorenjan 3y ago
        They have been given permission to drive at 12 knots because they produce much smaller wakes. https://www.hamnen.se/varldens-snabbaste-elfartyg-far-kora-fort-i-lagfartsomraden/ https://www.hamnen.se/varldens-snabbaste-elfartyg-far-kora-f...
        HALtheWise 3y ago
        Candela has been granted a waiver for the 12 knot speed limit in Stockholm, presumably because they make way less wake. Places like the San Francisco Bay are also clear examples of not-the-ocean but no-speed-limits. https://candela.com/candela-p-12-enables-public-transport-faster-than-cars-and-subway/ https://candela.com/candela-p-12-enables-public-transport-fa...
      - roflyear 3y ago
        Why do you need a ferry for a small lake? Anything you'd need a ferry for won't be much distinguishable from an ocean. https://www.youtube.com/watch?v=PebbX8uzyPI https://www.youtube.com/watch?v=PebbX8uzyPI
- wood_spirit 3y ago
  There are lots of videos on YouTube of the smaller C8 in choppy seas and crossing the wakes of other boats. I happened to see one for real gliding over some waves big enough to give me a bumpy ride in a conventional motorboat. So they do better than a conventional motorboat in the kind of normal rough sea. There must be some wave height that starts to give it problems, but it’s up past where normal little motorboats become hampered too.
  - roflyear 3y ago
    Can you link? I don't see anything that is more than "average" waves for the sea.
    - Sayrus 3y ago
      I think the video wood_spirit is referencing to is https://www.youtube.com/watch?v=2i2Zf9WVlNY https://www.youtube.com/watch?v=2i2Zf9WVlNY It's not extreme weather and the waves don't reach the length of the foil itself. I'm curious as well as to what happens on rough seas.
      - roflyear 3y ago
        Also totally different boat eh. Those waves are probably a little bigger than they look, but yes, definitely "better than average" I would say.
    - wood_spirit 3y ago
      A quick search for “candela c8 rough” finds some? Boy do I want one. For those calm days though. The quietness is another big draw. I have a 4stroke and it’s so peace destroying.
- helsinkiandrew 3y ago
  Video of one of their smaller "speedboats": https://www.youtube.com/watch?v=2i2Zf9WVlNY https://www.youtube.com/watch?v=2i2Zf9WVlNY I guess they can operate in waves that don't reach the hull? At least sideways EDIT: Their FAQ says the speedboat can handle 1.2M high waves: A Candela generally outperforms regular leisure boats in rough weather. The maximum wave height when foiling is approximately 1.2 meters from wave peak to valley. https://candela.com/faq/ https://candela.com/faq/
  - sergioisidoro 3y ago
    That video has the title "extreme weather". That's a very liberal use of the word "extreme"
    - mbrameld 3y ago
      It's extreme relative to the operating capabilities of the hydrofoil.
    - silvestrov 3y ago
      Now try the North Sea on a windy day: https://www.youtube.com/watch?v=TYzIWngs_T8 https://www.youtube.com/watch?v=TYzIWngs_T8 Watch the helicopter coming in to land 30 seconds into the movie. It lands at the end.
      - Gud 3y ago
        I doubt these small taxis are designed for the North Sea though.
        chrisco255 3y ago
        No these are mostly meant for rivers and intercoastal waterways. They're not going to be used for intercontinental travel.
        tyfon 3y ago
        They would be perfect for the public boat transportation system in the Oslo fjord between the islands there.
- tauntz 3y ago
  Hydrofoiling boats have been in commercial use for quite some time. I've taken one[1] between Estonia and Finland a couple of times but these are sadly not operating anymore. 1. https://images.delfi.ee/media-api-image-cropper/v1/02cc3aa0-b8f1-11eb-98b6-49bcde121acf.jpg https://images.delfi.ee/media-api-image-cropper/v1/02cc3aa0-...
  - nine_k 3y ago
    The Greek apparently still operate hydrofoil boats between islands on Mediterranean sea. Sea, not river.
    - riffraff 3y ago
      Same in Italy. Both sea and lakes.
      - KWxIUElW8Xt0tD9 3y ago
        I recall a hydrofoil on Lake Garda -- obviously lots of power required -- it was much louder than the normal ferries on that lake.
        nine_k 3y ago
        Some hydrofoil ships are powered by turbines, which produce a high-pitch whine, much more noticeable at a distance than the low-frequency rumbling of a diesel.
  - ge96 3y ago
    jet foil in Japan https://www.youtube.com/watch?v=e_lKISuF5Y4 https://www.youtube.com/watch?v=e_lKISuF5Y4 edit: shorter video
    - tim333 3y ago
      I think that's a Boeing 929 Jetfoil. They've been going since 1974 https://en.wikipedia.org/wiki/Boeing_929_Jetfoil https://en.wikipedia.org/wiki/Boeing_929_Jetfoil
- HumblyTossed 3y ago
  Wouldn't / Shouldn't they slow down out of hydrofoil speed when they enter rough seas? I would imagine that would be the prudent thing to do.
- acyou 3y ago
  Here's old footage of the foilborne Canadian Navy hydrofoil HMCS Bras D'Or from the 1970s, with some rough sea action right at the start of the video. Doesn't look like a smooth ride, and must be a huge stress on the hydrofoil structure: https://www.youtube.com/watch?v=XVYSUWEi-WQ&ab_channel=imaxguy https://www.youtube.com/watch?v=XVYSUWEi-WQ&ab_channel=imaxg... I think that as a general rule, longer vessels tend to be more seaworthy, they don't get swallowed by waves.
  - eschneider 3y ago
    Absolutely not true. Long vessels have different problems with waves, like having the bow AND stern lifted by waves at the same time, so you have a whole different set of failure modes.
    - acyou 3y ago
      Interesting, but I think many ocean-going vessels tend to be fairly long for good reason, with the bigger, longer ones also being faster and more capable in rough seas. Offshore commercial fishing boats are an example of shorter ocean-going boats. I think they would normally prefer to avoid storm seas if possible. They have to head up and turn into the waves, they can't take them sideways. One example of when people thought that a big, long boat would be more seaworthy, was the Titanic, which sank in 1912 after hitting an iceberg. But it wasn't the waves that did it. I think big, long and strong boats are pretty great in rough seas. If I was crossing the Atlantic, I think I'd rather be in a bigger boat, provided that it doesn't break up or develop any leaks.
      - stcredzero 3y ago
        I think I'd rather be in a bigger boat, provided that it doesn't break up This is a very high structural demand. Torpedoes work best, when they can effectively "lift" the keel, breaking the back of the ship. (Not exactly, but kind of, IIRC.) Very high sea swells apparently do the same thing! When there's far less buoyancy supporting one end of the ship than the other, the entire ship has to act as a cantilever. At the size of large ships, the square-cube law dominates, and the ship is far more fragile at that scale than a model boat would be. Even steel structures at that scale are flex-y.
- btbuildem 3y ago
  I imagine one of the challenges would be getting up to foiling speed in rough waters. From the videos I've seen, once the hull of a foil boat is out of the water, the ride is much less affected by waves.
  - devindotcom 3y ago
    they take off at around 7-8 knots, so as long as you can get up to that you're good. the motors and wing stay well below the water, the candelas do wave detection as well IIRC.
- deleted 3y ago
  [deleted]
- yencabulator 3y ago
  It's intended for use in coastal waters in the Baltic Sea, around lots of islands and behind the Danish straits that significantly tame incoming winds & waves: > P-12 [...] will halve commuting times in Stockholm from 2024. In the waves hydrofoils can handle, they're more comfortable than traditional boats -- the waves don't move the boat around as much.
- aidenn0 3y ago
  The deeper the lifting surface the larger the waves can be. You need the waves to not have too much of an impact at their peak while the foil still being underwater at the trough. Unless the foils can extend and rectract[1], the depth of the lifting surface impacts minimum draft of the ship as well. 1: Or fold, though with folding foils, you need to transition from foiling to floating where the water is deep enough, then float into the shallower water.
- chrisweekly 3y ago
  In general, hydrofoils provide a smooth ride as the vessel is lifted out of the chop. But in more extreme conditions, the hull can nosedive or otherwise slam back down into the water, at which point it's lost its momentum required to stay in foiling mode.
- smileysteve 3y ago
  I foil and efoil as a hobby; Once on foil, surface waves have no impact as long as you keep the foils in the water -- this means observing and adjusting attitude. If you do it well, you can maintain full speed and only feel the attitude changes (no bumps). Though, if it is very windy and wavy on the ocean/lake it is more difficult to develop foiling speed to take off. The reason why Candela is pioneering sub surface foils now is because it takes a reasonable amount of sensors and computation to avoid the foil breaching. For the most part, you wouldn't want to take a sub surface foiling vessel flying out in a storm with significant swells, but that's not what most boating is anyway.
- jasonwatkinspdx 3y ago
  Depends on the height of the waves relative to the height the foiling boat flies at. There's a reason those America's Cup boats and the big ocean going trimarans that use foils have quite different designs. The biggest issue is that if the foiling fails the boat has a tendency to bury the bow quite violently. This killed an AC sailor a decade or so ago. Foils make sense for inland waterways but making them work for the ocean proper is considerably more difficult. I'm no naval architect but this boat is awfully narrow in beam which is probably its biggest limitation.
- mlhpdx 3y ago
  Foiling sailboats deal with pretty substantial wave action, including open ocean storms. It’s all in the design. What’s really shocking to me is how slow this ferry is compared with those foiling sailboats which can reach upwards of 90 km/h.
- briffle 3y ago
  Navier boats in the bay area has a very high end luxury electric hydrofoiling boat, and this guy took a tour in much rougher waves, with a wife that is easily sea sick. they did fine, since you are no longer riding up and down the waves, more through them. Also, they use much, much less power once they are up on the hydrofoil, since they have much less resistance, just takes a bit to get up to speed first (which electric motors are great for) https://www.youtube.com/watch?v=HQbT4pr5ylE&t=6s https://www.youtube.com/watch?v=HQbT4pr5ylE&t=6s https://www.navierboat.com/ https://www.navierboat.com/
- spanktheuser 3y ago
  I have taken a several hour hydrofoil ride in the Mediterranean in moderate swells. The ride is deeply nauseating as the foils are positioned towards the outside corners and (on this 200+ passenger craft) catch the swells independently. The result a ride with similar pitch and roll as a traditionally-hulled ferry, with far more yaw and far less periodicity.
  - Candelaboat 3y ago
    Mikael at Candela, the hydrofoil maker, here. Our P-12 uses submerged hydrofoils and emplys a digital Flight controller, which stabilizes the craft by adjusting the angle of attack of the foils 100 times per second. So the pitching and heaving you found nauseating in the old Soviet Raketa and Kometa hydrofoils don't exist in P-12 - it's smooth sailing even in. chippy weather. Watch this video: https://www.youtube.com/watch?v=xIp9OkMzZkM https://www.youtube.com/watch?v=xIp9OkMzZkM
- mstade 3y ago
  I can speak to this a bit, having piloted a Candela (the speed boat version, I forget the number) on the Swedish west coast where seas can get notoriously choppy seemingly out of nowhere. This is a couple of years ago though so maybe they've improved things since. The impact of any waves higher than maybe a meter is likely to make the software take you in for a rather rude landing, and quick stop. It's unlike any boat of that size I've piloted, it was very heavy and it never felt like you were totally in control, with some small but quite noticeable latency between input and action. Felt more like piloting a larger ship than a small speed boat. The fact that it felt like you were at the mercy of the controlling software meant it became a very anxious ride as soon as you ran into a bit of choppy waters. When flying it was a very nice ride, but when you're not you have to go very slow or you quickly run out of battery. It was not particularly pleasant doing 3-4 knots in choppy waters, even if it did seem rather stable presumably due to the wide base, low height and deep rudders (foils). Fine boat in calm seas for sure, but I wouldn't use it for anything else. Should do fine in fair weather in central Stockholm though.
MuffinFlavored 3y ago
> Ferries are by far the most polluting form of transportation today Interesting The video also says that if it didn't plane up into hydrofoil-mode, it'd need to use enough energy to push 12 tons (full weight) through water. How much does it need to push in hydro-foil mode/what kind of percentage reduction are we looking at? It fits 30, 20, or 12 passengers depending on configuration and cost €1.7m. Which EU country is willing to buy like... 100 of these? It can't be cheap to ride if it can only hold 30 passengers max?
- JoachimS 3y ago
  There are quite a few ferries with capacity around 30 passengers in service in Sweden. Most of them burning diesel.
  - MuffinFlavored 3y ago
    Ah, shows how uncultured I am for not knowing that. I'm used to 30 people all crammed into one grocery aisle pushing each other for a $6 box of sugary cereal at WalMart in America so it seemed like an "insignificant" number in terms of transportation. (slightly kidding)
  - nemetroid 3y ago
    There are? Where?
    - m_eiman 3y ago
      In the archipelagos near Stockholm and Gothenburg, for example. There's a list of the nationally financed routes here: https://www.trafikverket.se/resa-och-trafik/farjetrafik/ https://www.trafikverket.se/resa-och-trafik/farjetrafik/ Then there are regionally and locally financed routes as well.
      - nemetroid 3y ago
        The ferries in that link are all road ferries. Most of them take at least 30 cars, and a lot more than 30 passengers. Most of the archipelago ferries in Gothenburg take around 300 passengers. The smallest one I could find on Styrsöbolaget's site takes 165: https://www.styrsobolaget.se/om-oss/fartyg/rivo https://www.styrsobolaget.se/om-oss/fartyg/rivo
frankus 3y ago
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
simonebrunozzi 3y ago
They tested an earlier version of the Candela in the lagoon of Venice, which has quite some waves caused by other motorboats. I don't think people were impressed.
- fkyoureadthedoc 3y ago
  Other than a Reuter's article[1] (and some very similar articles) hyping up the testing of what looks like a pretty normal boat but with hydrofoils, I can't find anything about the reception. Is this your personal experience? Do you know why people were unimpressed? 1. https://www.reuters.com/business/autos-transportation/swedish-flying-boat-aims-help-save-venice-waves-2021-06-07/ https://www.reuters.com/business/autos-transportation/swedis...
  - simonebrunozzi 3y ago
    I attended the boat show, tried the Candela, and heard numerous comments about it.
  - KineticLensman 3y ago
    Don’t know the specifics but there is a lot of hostility in Venice towards boats that aren’t respectful of the canal system, where wake can cause a lot of annoyance / damage.
sergioisidoro 3y ago
I'm wondering if this solution lands too much in between usable options. Long sea passages might have rougher weather which is not great for hydrofoils and might be too long for battery ranges. In short passages in inland bodies of water (with better wave conditions for hydrofoils and friendlier to battery ranges), do you have enough distance to start gliding in order to get the benefits of hydrofoil?
- simonbarker87 3y ago
  The high speed ferry on Lake Como uses a foil (although not as smooth as this, I’d almost say it is semi-flying perhaps) and there is more than enough distance between the ports to benefit from this Candela boat. The slow stopper ferry probably wouldn’t be a good option for this foil version (depends on acceleration time to flight I guess) though as the stops are pretty close together.
- ajmurmann 3y ago
  When I used to visit the island of Ischia with some regularity there used to be hydrofoils connecting it to the other island and Naples. Worked great!
louwrentius 3y ago
Always cool to see boats like this, never ceases to amaze me. Would have been interesting to know more about power, battery capacity, runtime, charging and so on. I'm into solar and LiFePo4 batteries and for those who have little experience with batteries or maybe lead acid, it's just so unbelievable magic how well this stuff works (Or how bad lead acid really is). And what is possible. There is a lot of engineering ahead of us, but the energy transition is in my view more of a political topic than a technical engineering challenge.
capableweb 3y ago
Correct me if I'm wrong, but isn't that Grafana being used in the boat dashboard? At least some of the widgets seems to either be very Grafana inspired, or straight up pulled from the Grafana UI. Probably the last place I'd expect that memory-hungry and CPU-inefficient UI to appear.
- tetris11 3y ago
  I guess your comment deliberately begs: are there any better?
- reliablereason 3y ago
  > Probably the last place I'd expect that memory-hungry and CPU-inefficient UI to appear. In a prototype with batteries large enough to heat and power a house for weeks? The power consumption of the navigation electronics is probably not a big concern. I would have put linux and a fullscreen electron app on those screens.
  - gosub100 3y ago
    I didn't read their comment as "drains the battery", more like "slows your computer down and eventually freezes". That could still be fine if you anticipate it (and as you said, it's a prototype) and the control system (throttle, rudder) doesn't depend on it.
- itsyaboi 3y ago
  Its almost certainly some RTOS like QNX.
rcpt 3y ago
Can't wait to cruise up to some Central California surf lineups with all my foiling buddies in one of these
chakintosh 3y ago
The design language was screaming Polestar then I scrolled and it turned out it was indeed using Polestar batteries.
UrineSqueegee 3y ago
this is really really old tech, these transport vehicles already exist for about 2 decades now. Here's one I used to take very regularly. https://www.facebook.com/watch/?v=176682457397144 https://www.facebook.com/watch/?v=176682457397144
kristofferR 3y ago
What are the reasonable size limits of this tech? Does it have positive or negative economics of scaling (does hydrofoiling on bigger electric ships get cheaper or more expensive per weight unit), or is there a ship size limit where the equation flips?
- lstodd 3y ago
  I think it's not possible to fit enough batteries by weight to scale this. Consider the Voskhod boat which at 28 tons and 60 km/h has to have ~800kW engine. To have any useful range the battery mass and charge time would be prohibitive. Turbodiesel and/or gas turbine work just fine though. https://en.wikipedia.org/wiki/Voskhod_(hydrofoil) https://en.wikipedia.org/wiki/Voskhod_(hydrofoil)
- smileysteve 3y ago
  As length increases so do the support/balancing requirements between multiple foils (front vs rear); As weight increases, lift may want to be increased to keep a low liftoff speed. As lift increases, speed and maneuverability decrease.
greedo 3y ago
I once took the hydrofoil ferry from Seattle to Victoria, BC. It was fast, but it was still a 2 1/2 hour trip. Not sure what that ferry used for propulsion, but I assume diesel.
malkia 3y ago
Seems like real code :) https://imgur.com/a/OTNsf5X https://imgur.com/a/OTNsf5X (spotted from the video - looks like .cpp, Visual Studio Code as IDE)
- networkchad 3y ago
  [dead]
- lambda 3y ago
  They are using FreeRTOS, communicating over a CAN bus using CANopen. Looks like this is a shutdown routine, shutting down various devices. They seem to have separate tasks for propulsion control and GPS. Pretty standard fare for a vehicle controller.
carabiner 3y ago
WE HAVE DONE MUCH -- BUT THERE IS MUCH -- TO BE DONE
tobinfricke 3y ago
Also check out https://www.navierboat.com/ https://www.navierboat.com/, a competitor in this space. And an amazing historical progenitor: https://www.youtube.com/watch?v=E2i3EeUnku0 https://www.youtube.com/watch?v=E2i3EeUnku0 https://en.wikipedia.org/wiki/USS_Plainview https://en.wikipedia.org/wiki/USS_Plainview
- justsomehnguy 3y ago
  Raketa was a passenger, earlier and mass-produced one. https://en.wikipedia.org/wiki/Raketa_(hydrofoil) https://en.wikipedia.org/wiki/Raketa_(hydrofoil)
inasio 3y ago
In Vancouver there are gas stations specific for boats, I heard from an attendant at one of them that occasionally yachts stop by and fill in $50,000 worth of gas (and pay cash according to him). Hydrofoils in theory would cut a very significant chunk of that, even if still on gas-powered boats. Given that the technology has been around for many decades, I suspect there's got to be a showstopper that prevents its adoption (vulnerable to floating logs?), and I suspect simply making them electric won't alleviate that
- riffraff 3y ago
  But we've had those for decades, no? There's a bunch of "aliscafi" doing ferries in Italy for example, both at sea and on lakes.
  - smileysteve 3y ago
    Similar, but quite different. The tradition foiling ferries rely on a surface based foil which does reduce drag significantly, is not as efficient as a sub surface foil, but are easier to implement because they "ride" the surface so they don't require balancing technology. Candela is using sub surface foils, relying on water both above and below the foil which provides significantly more lift, and immune to surface irregularities (if properly predicted).
- xuhu 3y ago
  More like the logs are vulnerable to the hydrofoils. Those vertical wings look like they can slice anything in half.
  - inasio 3y ago
    Yeah, no. This is not Starwars or samurai anime, commonly found red cedar or Doug firs go from one to many feet wide
- moffkalast 3y ago
  The problem with hydrofoils is that they don't scale up very well. Practically all larger designs were always gas turbine powered to even be able to supply enough power for initial liftoff and guzzled kerosene at laughably unprofitable rates. Much like ekranoplans and hovercrafts they didn't really prove to be economical in the long run. This smaller bus-sized version might genuinely be at the limit of what makes sense with current battery and motor tech.
robotnikman 3y ago
Sort of related, a game I play (From the Depths) has an electric hydrofoil ship called the Candela in it... except its a Battleship with armed with large lasers and missiles.
rexreed 3y ago
Navier is also doing something similar: https://www.navierboat.com/ https://www.navierboat.com/ Navier has been very self-promotional, taking the boat and its founder on a tour all across the US selling (investors) and the community on hydrofoil-based boats.
bagels 3y ago
What's the business case for this? Where are people are willing to pay a lot more for ferry tickets (I have to assume these boats will be more expensive, and have a much lower weight capacity)?
pants2 3y ago
These have been around for a long time. SeaWorld had a hydrofoil boat experience back in 1965. I don't think the biggest problem was the lack of electrification but more the cost, safety, and limited areas where it can operate.
heikkilevanto 3y ago
Interesting. But what are the (un)likely failure modes?
- trackofalljades 3y ago
  Dude, it floats. It has the same failure mode as any other boat.
deleted 3y ago
[deleted]
Max-q 3y ago
Hydrofoils were in fashion during the 70s. Many were built 7n Norway and sold to South East Asia. As seen on James Bond. I wonder why they disappeared
dave333 3y ago
Boat == airship Hydrofoil == airplane
danecjensen 3y ago
Navier has a more smooth looking boat. It's also from the Bay Area so you know the tech is better. https://navierboat.com https://navierboat.com
bertil 3y ago
It's funny that they mention, “Our mission is to build a public transport system that is as easy and as convenient as on land,” because Stokcholm’s public transport system does include (in Summer) similar boats that are, for passengers, just as easy and convenient. I guess the current diesel engines are not as “easy and convenient” as the electric metropolitan rail, while this would likely be… It is a fantastic project and one that every city should buy.
SendItUp 3y ago
I’m wondering how they deal with unseen logs and kelp patches which one will invariably encounter. As a frequent kitefoiler these two things can ruin your day. Not only can debris damage your mast and foil but kelp and seaweed tend to aggregate and pretty quickly one can have tens of pounds wrapped around ones foil resulting compounding drag. Even with the momentum of the vessel I don’t see how it will be able to get on foil again after encountering floating patches of kelp.
jl2718 3y ago
Idea: Voith Schneider Propeller with changing blade path and angle such that it has thrust phase on one side and a lift phase on the other. Basically it would be two giant low-speed spinning hydrofoil discs. Heavy low-end torque for a direct-drive electric motor.
SergeAx 3y ago
"Ferries are by far the most polluting form of transportation there is" Wow. Is that a fact? I always thought that water transportation was the next cleanest after railroads.

330 points by JoachimS 3y ago

zknill 3y ago

The promo video has a perfectly flat body of water. I'd be interested to know what impact waves have on a hydrofoil.

Phenomenit 3y ago
There is another video on their channel that shows the technology in rougher weather and sea, seems to work fine.
- roflyear 3y ago
  Which video? None of the videos I see show in rough conditions - the worst is probably "better than average" from spending time on the ocean.
  - Phenomenit 3y ago
    This one: https://www.youtube.com/watch?v=2i2Zf9WVlNY https://www.youtube.com/watch?v=2i2Zf9WVlNY
    - 0xNotMyAccount 3y ago
      All vessels have limits on the sea state they can handle, particularly small vessels. Very large vessels can generally handle much more. You can see how much more the traditional small patrol vessel is bouncing out there, my spine hurts just watching. I could see this being used for pilot vessels and harbor patrol craft, for sure.
    - Tempest1981 3y ago
      Cool, definitely a smoother ride than the adjacent boat.
    - RationalDino 3y ago
      That isn't rough. According to another comment, the Candela can handle waves of up to 1.2 meters. But about half of waves in the open ocean are 2+ meters. So this boat can't handle a normal ocean sea.
      - jdmoreira 3y ago
        This is Sweden. I've lived in the east coast of Sweden for 10 years, never seen a wave and there is water everywhere. Now I'm from Portugal, so… no comparison really.
        RationalDino 3y ago
        Yes. The east coast of Sweden is the Baltic Sea, which is not an open ocean. This boat may be perfectly usable there. But that's still not a rough sea. Other than temperature, that is water that I'd be perfectly comfortable swimming in.
  - HALtheWise 3y ago
    I don't think the primary target for these boats is the ocean, they're mostly designed to operate on lakes, bays, rivers, etc
    - travoc 3y ago
      ...so places where 5 knot speed limits are often enforced to prevent wakes.
      - SamBam 3y ago
        Since they barely produce wakes when they are hydrofoiling, these rules can probably be changed.
        nine_k 3y ago
        But during the transition to the hydrofoil mode and back they produce a lot of waves and wake; seen this many times firsthand.
      - sorenjan 3y ago
        They have been given permission to drive at 12 knots because they produce much smaller wakes. https://www.hamnen.se/varldens-snabbaste-elfartyg-far-kora-fort-i-lagfartsomraden/ https://www.hamnen.se/varldens-snabbaste-elfartyg-far-kora-f...
      - HALtheWise 3y ago
        Candela has been granted a waiver for the 12 knot speed limit in Stockholm, presumably because they make way less wake. Places like the San Francisco Bay are also clear examples of not-the-ocean but no-speed-limits. https://candela.com/candela-p-12-enables-public-transport-faster-than-cars-and-subway/ https://candela.com/candela-p-12-enables-public-transport-fa...
    - roflyear 3y ago
      Why do you need a ferry for a small lake? Anything you'd need a ferry for won't be much distinguishable from an ocean. https://www.youtube.com/watch?v=PebbX8uzyPI https://www.youtube.com/watch?v=PebbX8uzyPI
wood_spirit 3y ago
There are lots of videos on YouTube of the smaller C8 in choppy seas and crossing the wakes of other boats. I happened to see one for real gliding over some waves big enough to give me a bumpy ride in a conventional motorboat. So they do better than a conventional motorboat in the kind of normal rough sea. There must be some wave height that starts to give it problems, but it’s up past where normal little motorboats become hampered too.
- roflyear 3y ago
  Can you link? I don't see anything that is more than "average" waves for the sea.
  - Sayrus 3y ago
    I think the video wood_spirit is referencing to is https://www.youtube.com/watch?v=2i2Zf9WVlNY https://www.youtube.com/watch?v=2i2Zf9WVlNY It's not extreme weather and the waves don't reach the length of the foil itself. I'm curious as well as to what happens on rough seas.
    - roflyear 3y ago
      Also totally different boat eh. Those waves are probably a little bigger than they look, but yes, definitely "better than average" I would say.
  - wood_spirit 3y ago
    A quick search for “candela c8 rough” finds some? Boy do I want one. For those calm days though. The quietness is another big draw. I have a 4stroke and it’s so peace destroying.
helsinkiandrew 3y ago
Video of one of their smaller "speedboats": https://www.youtube.com/watch?v=2i2Zf9WVlNY https://www.youtube.com/watch?v=2i2Zf9WVlNY I guess they can operate in waves that don't reach the hull? At least sideways EDIT: Their FAQ says the speedboat can handle 1.2M high waves: A Candela generally outperforms regular leisure boats in rough weather. The maximum wave height when foiling is approximately 1.2 meters from wave peak to valley. https://candela.com/faq/ https://candela.com/faq/
- sergioisidoro 3y ago
  That video has the title "extreme weather". That's a very liberal use of the word "extreme"
  - mbrameld 3y ago
    It's extreme relative to the operating capabilities of the hydrofoil.
  - silvestrov 3y ago
    Now try the North Sea on a windy day: https://www.youtube.com/watch?v=TYzIWngs_T8 https://www.youtube.com/watch?v=TYzIWngs_T8 Watch the helicopter coming in to land 30 seconds into the movie. It lands at the end.
    - Gud 3y ago
      I doubt these small taxis are designed for the North Sea though.
      - chrisco255 3y ago
        No these are mostly meant for rivers and intercoastal waterways. They're not going to be used for intercontinental travel.
      - tyfon 3y ago
        They would be perfect for the public boat transportation system in the Oslo fjord between the islands there.
tauntz 3y ago
Hydrofoiling boats have been in commercial use for quite some time. I've taken one[1] between Estonia and Finland a couple of times but these are sadly not operating anymore. 1. https://images.delfi.ee/media-api-image-cropper/v1/02cc3aa0-b8f1-11eb-98b6-49bcde121acf.jpg https://images.delfi.ee/media-api-image-cropper/v1/02cc3aa0-...
- nine_k 3y ago
  The Greek apparently still operate hydrofoil boats between islands on Mediterranean sea. Sea, not river.
  - riffraff 3y ago
    Same in Italy. Both sea and lakes.
    - KWxIUElW8Xt0tD9 3y ago
      I recall a hydrofoil on Lake Garda -- obviously lots of power required -- it was much louder than the normal ferries on that lake.
      - nine_k 3y ago
        Some hydrofoil ships are powered by turbines, which produce a high-pitch whine, much more noticeable at a distance than the low-frequency rumbling of a diesel.
- ge96 3y ago
  jet foil in Japan https://www.youtube.com/watch?v=e_lKISuF5Y4 https://www.youtube.com/watch?v=e_lKISuF5Y4 edit: shorter video
  - tim333 3y ago
    I think that's a Boeing 929 Jetfoil. They've been going since 1974 https://en.wikipedia.org/wiki/Boeing_929_Jetfoil https://en.wikipedia.org/wiki/Boeing_929_Jetfoil
HumblyTossed 3y ago
Wouldn't / Shouldn't they slow down out of hydrofoil speed when they enter rough seas? I would imagine that would be the prudent thing to do.
acyou 3y ago
Here's old footage of the foilborne Canadian Navy hydrofoil HMCS Bras D'Or from the 1970s, with some rough sea action right at the start of the video. Doesn't look like a smooth ride, and must be a huge stress on the hydrofoil structure: https://www.youtube.com/watch?v=XVYSUWEi-WQ&ab_channel=imaxguy https://www.youtube.com/watch?v=XVYSUWEi-WQ&ab_channel=imaxg... I think that as a general rule, longer vessels tend to be more seaworthy, they don't get swallowed by waves.
- eschneider 3y ago
  Absolutely not true. Long vessels have different problems with waves, like having the bow AND stern lifted by waves at the same time, so you have a whole different set of failure modes.
  - acyou 3y ago
    Interesting, but I think many ocean-going vessels tend to be fairly long for good reason, with the bigger, longer ones also being faster and more capable in rough seas. Offshore commercial fishing boats are an example of shorter ocean-going boats. I think they would normally prefer to avoid storm seas if possible. They have to head up and turn into the waves, they can't take them sideways. One example of when people thought that a big, long boat would be more seaworthy, was the Titanic, which sank in 1912 after hitting an iceberg. But it wasn't the waves that did it. I think big, long and strong boats are pretty great in rough seas. If I was crossing the Atlantic, I think I'd rather be in a bigger boat, provided that it doesn't break up or develop any leaks.
    - stcredzero 3y ago
      I think I'd rather be in a bigger boat, provided that it doesn't break up This is a very high structural demand. Torpedoes work best, when they can effectively "lift" the keel, breaking the back of the ship. (Not exactly, but kind of, IIRC.) Very high sea swells apparently do the same thing! When there's far less buoyancy supporting one end of the ship than the other, the entire ship has to act as a cantilever. At the size of large ships, the square-cube law dominates, and the ship is far more fragile at that scale than a model boat would be. Even steel structures at that scale are flex-y.
btbuildem 3y ago
I imagine one of the challenges would be getting up to foiling speed in rough waters. From the videos I've seen, once the hull of a foil boat is out of the water, the ride is much less affected by waves.
- devindotcom 3y ago
  they take off at around 7-8 knots, so as long as you can get up to that you're good. the motors and wing stay well below the water, the candelas do wave detection as well IIRC.
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yencabulator 3y ago
It's intended for use in coastal waters in the Baltic Sea, around lots of islands and behind the Danish straits that significantly tame incoming winds & waves: > P-12 [...] will halve commuting times in Stockholm from 2024. In the waves hydrofoils can handle, they're more comfortable than traditional boats -- the waves don't move the boat around as much.
aidenn0 3y ago
The deeper the lifting surface the larger the waves can be. You need the waves to not have too much of an impact at their peak while the foil still being underwater at the trough. Unless the foils can extend and rectract[1], the depth of the lifting surface impacts minimum draft of the ship as well. 1: Or fold, though with folding foils, you need to transition from foiling to floating where the water is deep enough, then float into the shallower water.
chrisweekly 3y ago
In general, hydrofoils provide a smooth ride as the vessel is lifted out of the chop. But in more extreme conditions, the hull can nosedive or otherwise slam back down into the water, at which point it's lost its momentum required to stay in foiling mode.
smileysteve 3y ago
I foil and efoil as a hobby; Once on foil, surface waves have no impact as long as you keep the foils in the water -- this means observing and adjusting attitude. If you do it well, you can maintain full speed and only feel the attitude changes (no bumps). Though, if it is very windy and wavy on the ocean/lake it is more difficult to develop foiling speed to take off. The reason why Candela is pioneering sub surface foils now is because it takes a reasonable amount of sensors and computation to avoid the foil breaching. For the most part, you wouldn't want to take a sub surface foiling vessel flying out in a storm with significant swells, but that's not what most boating is anyway.
jasonwatkinspdx 3y ago
Depends on the height of the waves relative to the height the foiling boat flies at. There's a reason those America's Cup boats and the big ocean going trimarans that use foils have quite different designs. The biggest issue is that if the foiling fails the boat has a tendency to bury the bow quite violently. This killed an AC sailor a decade or so ago. Foils make sense for inland waterways but making them work for the ocean proper is considerably more difficult. I'm no naval architect but this boat is awfully narrow in beam which is probably its biggest limitation.
mlhpdx 3y ago
Foiling sailboats deal with pretty substantial wave action, including open ocean storms. It’s all in the design. What’s really shocking to me is how slow this ferry is compared with those foiling sailboats which can reach upwards of 90 km/h.
briffle 3y ago
Navier boats in the bay area has a very high end luxury electric hydrofoiling boat, and this guy took a tour in much rougher waves, with a wife that is easily sea sick. they did fine, since you are no longer riding up and down the waves, more through them. Also, they use much, much less power once they are up on the hydrofoil, since they have much less resistance, just takes a bit to get up to speed first (which electric motors are great for) https://www.youtube.com/watch?v=HQbT4pr5ylE&t=6s https://www.youtube.com/watch?v=HQbT4pr5ylE&t=6s https://www.navierboat.com/ https://www.navierboat.com/
spanktheuser 3y ago
I have taken a several hour hydrofoil ride in the Mediterranean in moderate swells. The ride is deeply nauseating as the foils are positioned towards the outside corners and (on this 200+ passenger craft) catch the swells independently. The result a ride with similar pitch and roll as a traditionally-hulled ferry, with far more yaw and far less periodicity.
- Candelaboat 3y ago
  Mikael at Candela, the hydrofoil maker, here. Our P-12 uses submerged hydrofoils and emplys a digital Flight controller, which stabilizes the craft by adjusting the angle of attack of the foils 100 times per second. So the pitching and heaving you found nauseating in the old Soviet Raketa and Kometa hydrofoils don't exist in P-12 - it's smooth sailing even in. chippy weather. Watch this video: https://www.youtube.com/watch?v=xIp9OkMzZkM https://www.youtube.com/watch?v=xIp9OkMzZkM
mstade 3y ago
I can speak to this a bit, having piloted a Candela (the speed boat version, I forget the number) on the Swedish west coast where seas can get notoriously choppy seemingly out of nowhere. This is a couple of years ago though so maybe they've improved things since. The impact of any waves higher than maybe a meter is likely to make the software take you in for a rather rude landing, and quick stop. It's unlike any boat of that size I've piloted, it was very heavy and it never felt like you were totally in control, with some small but quite noticeable latency between input and action. Felt more like piloting a larger ship than a small speed boat. The fact that it felt like you were at the mercy of the controlling software meant it became a very anxious ride as soon as you ran into a bit of choppy waters. When flying it was a very nice ride, but when you're not you have to go very slow or you quickly run out of battery. It was not particularly pleasant doing 3-4 knots in choppy waters, even if it did seem rather stable presumably due to the wide base, low height and deep rudders (foils). Fine boat in calm seas for sure, but I wouldn't use it for anything else. Should do fine in fair weather in central Stockholm though.

MuffinFlavored 3y ago

> Ferries are by far the most polluting form of transportation today Interesting The video also says that if it didn't plane up into hydrofoil-mode, it'd need to use enough energy to push 12 tons (full weight) through water. How much does it need to push in hydro-foil mode/what kind of percentage reduction are we looking at? It fits 30, 20, or 12 passengers depending on configuration and cost €1.7m. Which EU country is willing to buy like... 100 of these? It can't be cheap to ride if it can only hold 30 passengers max?

JoachimS 3y ago
There are quite a few ferries with capacity around 30 passengers in service in Sweden. Most of them burning diesel.
- MuffinFlavored 3y ago
  Ah, shows how uncultured I am for not knowing that. I'm used to 30 people all crammed into one grocery aisle pushing each other for a $6 box of sugary cereal at WalMart in America so it seemed like an "insignificant" number in terms of transportation. (slightly kidding)
- nemetroid 3y ago
  There are? Where?
  - m_eiman 3y ago
    In the archipelagos near Stockholm and Gothenburg, for example. There's a list of the nationally financed routes here: https://www.trafikverket.se/resa-och-trafik/farjetrafik/ https://www.trafikverket.se/resa-och-trafik/farjetrafik/ Then there are regionally and locally financed routes as well.
    - nemetroid 3y ago
      The ferries in that link are all road ferries. Most of them take at least 30 cars, and a lot more than 30 passengers. Most of the archipelago ferries in Gothenburg take around 300 passengers. The smallest one I could find on Styrsöbolaget's site takes 165: https://www.styrsobolaget.se/om-oss/fartyg/rivo https://www.styrsobolaget.se/om-oss/fartyg/rivo

frankus 3y ago

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

simonebrunozzi 3y ago

They tested an earlier version of the Candela in the lagoon of Venice, which has quite some waves caused by other motorboats. I don't think people were impressed.

fkyoureadthedoc 3y ago
Other than a Reuter's article[1] (and some very similar articles) hyping up the testing of what looks like a pretty normal boat but with hydrofoils, I can't find anything about the reception. Is this your personal experience? Do you know why people were unimpressed? 1. https://www.reuters.com/business/autos-transportation/swedish-flying-boat-aims-help-save-venice-waves-2021-06-07/ https://www.reuters.com/business/autos-transportation/swedis...
- simonebrunozzi 3y ago
  I attended the boat show, tried the Candela, and heard numerous comments about it.
- KineticLensman 3y ago
  Don’t know the specifics but there is a lot of hostility in Venice towards boats that aren’t respectful of the canal system, where wake can cause a lot of annoyance / damage.

sergioisidoro 3y ago

I'm wondering if this solution lands too much in between usable options. Long sea passages might have rougher weather which is not great for hydrofoils and might be too long for battery ranges. In short passages in inland bodies of water (with better wave conditions for hydrofoils and friendlier to battery ranges), do you have enough distance to start gliding in order to get the benefits of hydrofoil?

simonbarker87 3y ago
The high speed ferry on Lake Como uses a foil (although not as smooth as this, I’d almost say it is semi-flying perhaps) and there is more than enough distance between the ports to benefit from this Candela boat. The slow stopper ferry probably wouldn’t be a good option for this foil version (depends on acceleration time to flight I guess) though as the stops are pretty close together.
ajmurmann 3y ago
When I used to visit the island of Ischia with some regularity there used to be hydrofoils connecting it to the other island and Naples. Worked great!

louwrentius 3y ago

Always cool to see boats like this, never ceases to amaze me. Would have been interesting to know more about power, battery capacity, runtime, charging and so on. I'm into solar and LiFePo4 batteries and for those who have little experience with batteries or maybe lead acid, it's just so unbelievable magic how well this stuff works (Or how bad lead acid really is). And what is possible. There is a lot of engineering ahead of us, but the energy transition is in my view more of a political topic than a technical engineering challenge.

capableweb 3y ago

Correct me if I'm wrong, but isn't that Grafana being used in the boat dashboard? At least some of the widgets seems to either be very Grafana inspired, or straight up pulled from the Grafana UI. Probably the last place I'd expect that memory-hungry and CPU-inefficient UI to appear.

tetris11 3y ago
I guess your comment deliberately begs: are there any better?
reliablereason 3y ago
> Probably the last place I'd expect that memory-hungry and CPU-inefficient UI to appear. In a prototype with batteries large enough to heat and power a house for weeks? The power consumption of the navigation electronics is probably not a big concern. I would have put linux and a fullscreen electron app on those screens.
- gosub100 3y ago
  I didn't read their comment as "drains the battery", more like "slows your computer down and eventually freezes". That could still be fine if you anticipate it (and as you said, it's a prototype) and the control system (throttle, rudder) doesn't depend on it.
itsyaboi 3y ago
Its almost certainly some RTOS like QNX.

rcpt 3y ago

Can't wait to cruise up to some Central California surf lineups with all my foiling buddies in one of these

chakintosh 3y ago

The design language was screaming Polestar then I scrolled and it turned out it was indeed using Polestar batteries.

UrineSqueegee 3y ago

this is really really old tech, these transport vehicles already exist for about 2 decades now. Here's one I used to take very regularly. https://www.facebook.com/watch/?v=176682457397144 https://www.facebook.com/watch/?v=176682457397144

kristofferR 3y ago

What are the reasonable size limits of this tech? Does it have positive or negative economics of scaling (does hydrofoiling on bigger electric ships get cheaper or more expensive per weight unit), or is there a ship size limit where the equation flips?

lstodd 3y ago
I think it's not possible to fit enough batteries by weight to scale this. Consider the Voskhod boat which at 28 tons and 60 km/h has to have ~800kW engine. To have any useful range the battery mass and charge time would be prohibitive. Turbodiesel and/or gas turbine work just fine though. https://en.wikipedia.org/wiki/Voskhod_(hydrofoil) https://en.wikipedia.org/wiki/Voskhod_(hydrofoil)
smileysteve 3y ago
As length increases so do the support/balancing requirements between multiple foils (front vs rear); As weight increases, lift may want to be increased to keep a low liftoff speed. As lift increases, speed and maneuverability decrease.

greedo 3y ago

I once took the hydrofoil ferry from Seattle to Victoria, BC. It was fast, but it was still a 2 1/2 hour trip. Not sure what that ferry used for propulsion, but I assume diesel.

malkia 3y ago

Seems like real code :) https://imgur.com/a/OTNsf5X https://imgur.com/a/OTNsf5X (spotted from the video - looks like .cpp, Visual Studio Code as IDE)

networkchad 3y ago
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lambda 3y ago
They are using FreeRTOS, communicating over a CAN bus using CANopen. Looks like this is a shutdown routine, shutting down various devices. They seem to have separate tasks for propulsion control and GPS. Pretty standard fare for a vehicle controller.

carabiner 3y ago

WE HAVE DONE MUCH -- BUT THERE IS MUCH -- TO BE DONE

tobinfricke 3y ago

Also check out https://www.navierboat.com/ https://www.navierboat.com/, a competitor in this space. And an amazing historical progenitor: https://www.youtube.com/watch?v=E2i3EeUnku0 https://www.youtube.com/watch?v=E2i3EeUnku0 https://en.wikipedia.org/wiki/USS_Plainview https://en.wikipedia.org/wiki/USS_Plainview

justsomehnguy 3y ago
Raketa was a passenger, earlier and mass-produced one. https://en.wikipedia.org/wiki/Raketa_(hydrofoil) https://en.wikipedia.org/wiki/Raketa_(hydrofoil)

inasio 3y ago

In Vancouver there are gas stations specific for boats, I heard from an attendant at one of them that occasionally yachts stop by and fill in $50,000 worth of gas (and pay cash according to him). Hydrofoils in theory would cut a very significant chunk of that, even if still on gas-powered boats. Given that the technology has been around for many decades, I suspect there's got to be a showstopper that prevents its adoption (vulnerable to floating logs?), and I suspect simply making them electric won't alleviate that

riffraff 3y ago
But we've had those for decades, no? There's a bunch of "aliscafi" doing ferries in Italy for example, both at sea and on lakes.
- smileysteve 3y ago
  Similar, but quite different. The tradition foiling ferries rely on a surface based foil which does reduce drag significantly, is not as efficient as a sub surface foil, but are easier to implement because they "ride" the surface so they don't require balancing technology. Candela is using sub surface foils, relying on water both above and below the foil which provides significantly more lift, and immune to surface irregularities (if properly predicted).
xuhu 3y ago
More like the logs are vulnerable to the hydrofoils. Those vertical wings look like they can slice anything in half.
- inasio 3y ago
  Yeah, no. This is not Starwars or samurai anime, commonly found red cedar or Doug firs go from one to many feet wide
moffkalast 3y ago
The problem with hydrofoils is that they don't scale up very well. Practically all larger designs were always gas turbine powered to even be able to supply enough power for initial liftoff and guzzled kerosene at laughably unprofitable rates. Much like ekranoplans and hovercrafts they didn't really prove to be economical in the long run. This smaller bus-sized version might genuinely be at the limit of what makes sense with current battery and motor tech.

robotnikman 3y ago

Sort of related, a game I play (From the Depths) has an electric hydrofoil ship called the Candela in it... except its a Battleship with armed with large lasers and missiles.

rexreed 3y ago

Navier is also doing something similar: https://www.navierboat.com/ https://www.navierboat.com/ Navier has been very self-promotional, taking the boat and its founder on a tour all across the US selling (investors) and the community on hydrofoil-based boats.

bagels 3y ago

What's the business case for this? Where are people are willing to pay a lot more for ferry tickets (I have to assume these boats will be more expensive, and have a much lower weight capacity)?

pants2 3y ago

These have been around for a long time. SeaWorld had a hydrofoil boat experience back in 1965. I don't think the biggest problem was the lack of electrification but more the cost, safety, and limited areas where it can operate.

heikkilevanto 3y ago

Interesting. But what are the (un)likely failure modes?

trackofalljades 3y ago
Dude, it floats. It has the same failure mode as any other boat.

deleted 3y ago

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Max-q 3y ago

Hydrofoils were in fashion during the 70s. Many were built 7n Norway and sold to South East Asia. As seen on James Bond. I wonder why they disappeared

dave333 3y ago

Boat == airship Hydrofoil == airplane

danecjensen 3y ago

Navier has a more smooth looking boat. It's also from the Bay Area so you know the tech is better. https://navierboat.com https://navierboat.com

bertil 3y ago

It's funny that they mention, “Our mission is to build a public transport system that is as easy and as convenient as on land,” because Stokcholm’s public transport system does include (in Summer) similar boats that are, for passengers, just as easy and convenient. I guess the current diesel engines are not as “easy and convenient” as the electric metropolitan rail, while this would likely be… It is a fantastic project and one that every city should buy.

SendItUp 3y ago

I’m wondering how they deal with unseen logs and kelp patches which one will invariably encounter. As a frequent kitefoiler these two things can ruin your day. Not only can debris damage your mast and foil but kelp and seaweed tend to aggregate and pretty quickly one can have tens of pounds wrapped around ones foil resulting compounding drag. Even with the momentum of the vessel I don’t see how it will be able to get on foil again after encountering floating patches of kelp.

jl2718 3y ago

Idea: Voith Schneider Propeller with changing blade path and angle such that it has thrust phase on one side and a lift phase on the other. Basically it would be two giant low-speed spinning hydrofoil discs. Heavy low-end torque for a direct-drive electric motor.

SergeAx 3y ago

"Ferries are by far the most polluting form of transportation there is" Wow. Is that a fact? I always thought that water transportation was the next cleanest after railroads.