this post was submitted on 15 May 2024
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Seagliders' 35-minute trips to Auckland closer with $145m deal (www.nzherald.co.nz)
submitted 5 months ago by [email protected] to c/[email protected]
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I'm pretty sceptical about ground effect planes, there's a very good reason why they've never really taken off, despite so many countries and organisations giving them a try over the years, but I'd love to know what everyone else thinks.

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[–] [email protected] 7 points 5 months ago* (last edited 5 months ago) (2 children)

I agree there appear to be very good reasons not to use these.

Foling at 500kmph (edit: more like 250kmph by the looks of it) 10 metres above the water seems to just be inherently bonkers as a means of mass transportation given the very limited room for error/failure that results in everyone on board being instantly killed. Planes and helicopters can glide/autorotate, ships move slower.

The 3d mock ups and carefully shot video of the first flight (that obscures the fact it's a very small scale model prototype) suggest vapour ware scam startup.

Honestly for the love of god, can we just have trains?

[–] [email protected] 3 points 5 months ago

A sea plane or float plane would be a much simpler, safer option, in my view.

[–] [email protected] 2 points 5 months ago

I honestly don't know who is dumb enough to believe they are going to be moving crowds over the water at 250km/h. That's just bonkers. We can't move cars and trains that fast FFS.

A typical turbo prop will cruise at around 400 km/h

Well maybe the investors are dumb enough.

[–] [email protected] 4 points 5 months ago

I want these to become a thing, because they're awesome. But I doubt it actually will.

Plus, there are much more efficient ways to move large numbers of people. Still, ground affect craft are neat.

[–] [email protected] 3 points 5 months ago (2 children)

This is basically a plane, right? And would be priced similar to a flight on a 12 seater plane, or perhaps even higher if they are taking you to central Auckland and saving you a taxi.

Although this brings Whangārei within commuting distance, I don't imagine it will be priced appropriately for people do daily commuting?

I'm also curious how far their batteries take them. So they can do Whangārei to Auckland in 35 mins, can they turn around and go back or do they need to spend 6 hours charging?

[–] [email protected] 3 points 5 months ago (1 children)

Should be a lot more efficient than a plane, and able to carry more with a smaller wingspan and less power required.

https://youtu.be/yVdH_dYlVB8

https://youtube.com/playlist?list=PLXvxJNOIXBsMyYPykdtoWRj1m5DRn4CNx

[–] [email protected] 3 points 5 months ago* (last edited 5 months ago)

That's awesome, thanks for sharing! For your first link about the Soviet programme, they talk about all the issues, and hypothesize that getting these working properly probably requires larger aircraft than has ever been built, because these can fly higher under ground effect, up to 10 or 20 metres.

Given the original article here states these tiny planes will fly 10 metres above the sea, I am skeptical that they will properly operate under ground effect. Wikipedia states that the effect is about half of the craft's wingspan, putting it at a lot less than the 10 metres claimed.

And as mentioned in this comment chain, the nice videos in the article are actually all little models and it seems they haven't actually built any of these craft at full size, so the chances are pretty low that anything will actually come of it.

[–] [email protected] 2 points 5 months ago (1 children)

Kinda, although an aircraft that operates exclusively in ground effect is explicitly not an aircraft as far as CAA is concerned, so they're outside their rules.

As far as recharge time is concerned, I assume they would be able to fast charge in half an hour or so, like any other electric vehicle.

[–] [email protected] 3 points 5 months ago (1 children)

Kinda, although an aircraft that operates exclusively in ground effect is explicitly not an aircraft as far as CAA is concerned, so they’re outside their rules.

Interesting!

As far as recharge time is concerned, I assume they would be able to fast charge in half an hour or so, like any other electric vehicle.

For EVs to charge in 30 mins, you need some pretty beefy power infrastructure, it's not something available at residential houses. So if the battery capacity is a lot higher, you might not be able to get charged in that short amount of time. I'd expect power usage to be much higher for this plane than an EV, given it's a lot larger.

But now I think about it, it might not be that much larger. Having just read up on the concept of ground-effect I guess it may be more efficient than an EV, so perhaps you'd get away with batteries about twice as large as a long-range EV? Given the right setup you could probably still do an 80% charge in under an hour, so flying each way on a 2 hour schedule would be pretty doable. Run a second one to double the frequency.

[–] [email protected] 2 points 5 months ago (1 children)

They're operating from the CBD, so getting power to a charging station is relatively straightforward, and there are technologies available to recharge a vehicle quite fast, there is a standard being developed for trucks that will be over a megawatt of charging capacity. The east by West electric boat uses two chargers, from my understanding.

[–] [email protected] 2 points 5 months ago* (last edited 5 months ago) (1 children)

The east by West electric boat uses two chargers, from my understanding.

Haha can't believe I didn't think of that. I guess there is a battery pack in each wing, no reason not to plug in two chargers.

I also didn't consider that while EV hyper chargers pull a lot of power, the sites often have multiple, so a larger amount of power is available than what is going through one charger. Charging is probably not as big of a deal as I originally assumed.

Probably the only limitation is how they prevent the battery getting too hot during charging, but I'm pretty sure a lot of EVs already have active battery cooling so an extension of that is probably fine as well.

[–] [email protected] 2 points 5 months ago

I don't know if they split the pack, or just have multiple chargers working side by side. I know Tesla have done similar when testing the Semi, just use multiple chargers at once.

The vehicle being charged already tells the charger what to do anyway.

[–] [email protected] 2 points 5 months ago (1 children)

[–] [email protected] 1 points 5 months ago

Pretty apt comparison actually.

[–] [email protected] 2 points 5 months ago* (last edited 5 months ago) (1 children)

I think that anything with such narrow operating parameter is always limited. Just the way things work. Take rockets - ones to put humans in orbit are very different than say sounding rockets, or other sub-orbitals, or even ones for satellites (and those vary based on LEO or GeoSynch).

Soviet Union used ground effects planes as naval vessels with missiles (Ekranoplan), which I guess the tradeoffs made sense.

[–] [email protected] 2 points 5 months ago (1 children)

The Soviets also crashed one of their ground effect planes, killing all the crew. I understand they were also very costly to operate.

[–] [email protected] 3 points 5 months ago (1 children)

Electric ground effect has a major advantage vs the jet turbine driven ones.

It does not have to suck in massive volumes of air close to the ground....sea water is not good for jet turbines.

[–] [email protected] 3 points 5 months ago (1 children)

Sea water is a nightmare for anything mechanical, in my experience, but electronics can at least be sealed effectively. Usually.

The biggest reason I'm so sceptical about this, is every other use case I've seen for electric vehicles or vessels has been something that's already a proven concept. Cars, trucks, planes, harbour ferries, they are all a proven concept, we're just moving to a different fuel.

Ground effect planes, on the other hand, have never been proven with any fuel type.

[–] [email protected] 3 points 5 months ago

Good point.... We will just have to watch and find out. Ground effect theory, and somewhat practice is sound.

[–] [email protected] 2 points 5 months ago (1 children)

despite so many countries and organisations giving them a try over the years

Who other than the Soviet Union ever did any sort of serious attempt?

[–] [email protected] 3 points 5 months ago

There's been a handful of small passenger ones built in a number of countries, including some aircraft converted into ground effect planes. Germany has built a few, and Iran apparently uses them to some degree.

https://en.m.wikipedia.org/wiki/Liberty_Lifter

And then there's this monster.

[–] [email protected] 1 points 5 months ago

Better not use these if there’s any significant waves around… 10 metres above sea level is not as safe as you might think.

https://en.m.wikipedia.org/wiki/Rogue_wave