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The Hawai’i Seaglider Initiative: A new approach to travel between the islands

hawaiiseaglider.org

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Re: The Hawai’i Seaglider Initiative: A new approach to travel between the islands

#91

Post by jauntywundrkind »

tlb wrote: post #58

The aerodynamic benefit of flying in ground effect is fairly small, and the disadvantage is that rogue waves can just randomly splash that high. The current plane's wingspan is 65 feet, which probably means it flies about 32 feet (half a wingspan) off the water. Rogue waves can easily be that high in mild weather, and hitting even a small amount of water at 200 mph (claimed cruise speed) is bad. Lots of sea birds too…

Is this actually a problem?

This feels like something that an automated system could pretty easily detect, up to the range of visibility, and raise the seaplane up if this happens.

Further, this is an inter-island route. Adding dedicated monitoring seems imminently doable.

Yes, this is a concern. No, it's not hard to deal with.

Re: The Hawai’i Seaglider Initiative: A new approach to travel between the islands

#93

Post by jauntywundrkind »

ghaff wrote: post #87
throw0101d wrote: post #82

Meta: it seems like Hawaii (Hawai'i) would be a pretty good place to be able to do public transit, given the not-huge distances involved on any particular island, but AFAICT, it's not very good there. Also it seems like it's not very bike / cycling friendly either: * https://www.civilbeat.org/2022/07/keona-blanks-when-it-comes...

You do have to separate Honolulu from pretty much everywhere else in the islands. Most of the small town/cities/resort communities are quite walkable once you get there. Everything else is extremely spread out--rural for the most part by any reasonable measure. Also often difficult terrain.

This suggests to me that there's a perhaps even better application for an eco-friendly high-speed water transport: intra-island transport!

Rather than try to build and maintain difficult overland transport at land-speed, we could seaglider between coastal villages.

Re: The Hawai’i Seaglider Initiative: A new approach to travel between the islands

#94

Post by mock-possum »

jauntywundrkind wrote: post #91
tlb wrote: post #58

The aerodynamic benefit of flying in ground effect is fairly small, and the disadvantage is that rogue waves can just randomly splash that high. The current plane's wingspan is 65 feet, which probably means it flies about 32 feet (half a wingspan) off the water. Rogue waves can easily be that high in mild weather, and hitting even a small amount of water at 200 mph (claimed cruise speed) is bad. Lots of sea birds too…

Is this actually a problem? This feels like something that an automated system could pretty easily detect, up to the range of visibility, and raise the seaplane up if this happens. Further, this is an inter-island route. Adding dedicated monitoring seems imminently doable. Yes, this is a concern. No, it's not hard to deal with.

Isn’t the deal with rogue waves that they’re rogue? They’re not just big waves that slowly and predictably approach you from the horizon, then continue on their way past you in the opposite direction - they arise suddenly, unpredictably, without warning. One minute everything is smooth sailing, peaks and troughs of a few feet, and then suddenly the sea drops out from under you and now you’re in a 30 foot trough, or the sea just bunches up and you’re facing a 30 foot wave - maybe it grows out of nowhere, with you on top of it.

Re: The Hawai’i Seaglider Initiative: A new approach to travel between the islands

#95

Post by jauntywundrkind »

mock-possum wrote: post #94
jauntywundrkind wrote: post #91

Earlier quoted context omitted.

Is this actually a problem? This feels like something that an automated system could pretty easily detect, up to the range of visibility, and raise the seaplane up if this happens. Further, this is an inter-island route. Adding dedicated monitoring seems imminently doable. Yes, this is a concern. No, it's not hard to deal with.

Isn’t the deal with rogue waves that they’re rogue ? They’re not just big waves that slowly and predictably approach you from the horizon, then continue on their way past you in the opposite direction - they arise suddenly, unpredictably, without warning. One minute everything is smooth sailing, peaks and troughs of a few feet, and then suddenly the sea drops out from under you and now you’re in a 30 foot trough, or…

It seems like if it is a nodal-point/interference issue, the probability has to be so small because it's a small area & momentary.

You're probably right. But it also makes me think this might be a fantastically unlikely problem. I wonder where we'd get data on the likeliness of rogue waves of what size around Hawaii. It also stirs wondermemt about wavelength/periodicity of wave systems.

Re: The Hawai’i Seaglider Initiative: A new approach to travel between the islands

#96

Post by worik »

jauntywundrkind wrote: post #95
mock-possum wrote: post #94

Earlier quoted context omitted.

Isn’t the deal with rogue waves that they’re rogue ? They’re not just big waves that slowly and predictably approach you from the horizon, then continue on their way past you in the opposite direction - they arise suddenly, unpredictably, without warning. One minute everything is smooth sailing, peaks and troughs of a few feet, and then suddenly the sea drops out from under you and now you’re in a 30 foot trough, or…

It seems like if it is a nodal-point/interference issue, the probability has to be so small because it's a small area & momentary. You're probably right. But it also makes me think this might be a fantastically unlikely problem. I wonder where we'd get data on the likeliness of rogue waves of what size around Hawaii. It also stirs wondermemt about wavelength/periodicity of wave systems.

> nodal-point/interference issue, the probability has to be so small because it's a small area & momentary.

Not necessarily, especially around costal islands in the ocean

The confluence of wind and tide around islands causes unpredictable ant violent sea conditions

Costal sailors know this

Re: The Hawai’i Seaglider Initiative: A new approach to travel between the islands

#97

Post by mkl »

phire wrote: post #66
mkl wrote: post #27

Earlier quoted context omitted.

Neat! I couldn't see where they intend to run it (though it may be hidden in an article). They give a 300km range, which is almost exactly Christchurch–Wellington, so I wonder if that's possible.

Christchurch to Wellington is a bit of a stretch for the range. It's too far to use the Harbour infrastructure at either end. You would have to build a pier on the southern side of Wellington (say Island Bay) and then use New Brighton pier. That works out to about 295 km. With only 300km range, it's hard to find good routes in NZ.

According to https://www.stuff.co.nz/business/128397643/transport-revolut... they do intend to do Christchurch–Wellington. Possibly only with the bigger 100-seater ones they've ordered though.

Re: The Hawai’i Seaglider Initiative: A new approach to travel between the islands

#98

Post by bruce511 »

eesmith wrote: post #46
bruce511 wrote: post #34

Earlier quoted context omitted.

>> Probably just a tourist attraction. Yes and no. One the one hand, absolutely a tourist attraction. Its projected to be cheaper than flying, and hopes to be a lot less hassle. (Expect pushback from the airlines. ) However small capacity, cheap, accessible transport is a boon for islanders living in archipelago. For starters you're not bound to islands big enough for an airport. Given that the vehicle is electric, a…

> for starters you're not bound to islands big enough for an airport. The competition for that space is seaplanes, including both floatplanes and flying boats, which have been around for a century. Electric versions of those exist, like https://harbourair.com/corporate-responsibility/goingelectri... , and https://el-fly.no/ wants to build an electric amphibious flying boat. Yes, a ground-effect vehicle has better win…

>> The competition for that space is seaplanes, including both floatplanes and flying boats

Airplanes operate in a hostel environment where the penalty for failure is severe. The translates into a lot of (good) regulation which makes planes expensive to make, and expensive to maintain.

Ground effect vehicles are more in the car/boat space when it comes to mechanical failure. Sure I'm not saying it can be made of some wire and duct tape, but the necessary mechanical standard is a -lot- lower (ie cheaper.)

>> . If you want to minimize environmental harm

Sure. Or stay home. There's always something better. But that wasn't the hypothesis. The statement was that its better than planes or (motor) boats.

Frankly, if an electric craft is charged from solar or wind, its already as good as a sailboat.

Re: The Hawai’i Seaglider Initiative: A new approach to travel between the islands

#99

Post by bink »

XEKEP wrote: post #38
bink wrote: post #31

Earlier quoted context omitted.

Which inter-island ferry are you referring to? Hawaii doesn't have them.

see Maui to Lanai ferry https://go-lanai.com/

Interesting. That's only the very short trip between Maui and Lanai though. Still an improvement over the zero ferries that existed back when I lived there.
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