Are GEVs a good idea?

[A_Kid1234]

Would giant ground effect vehicles such as the aerocon Wingship and the Boeing pelican actually be useful in today’s economy or a waste of money?

 

[dan_inbox]

Hint 1: all existing prototypes have been abandoned.
Hint 2: and even those few prototypes were only financed by the various militaries, for extremely niche applications.
Hint 3: not a single one has successfully operated commercial revenue, AFAIK.

Then it is up to your own definition of good idea vs waste of money.


In my mind, the parallel is very clear with commercial lighter-than-air giants: even though there is an endless stream of con men who claim that their solution will beat all the previous failed attempts, and an apparently equally endless stream of people with more money than smarts who are willing to invest in tech they don't understand, the cycle always ends up the same way: oops...

 

[A_Kid1234]

Hint 1: all existing prototypes have been abandoned.
Hint 2: and even those few prototypes were only financed by the various militaries, for extremely niche applications.
Hint 3: not a single one has successfully operated commercial revenue, AFAIK.

Then it is up to your own definition of good idea vs waste of money.


In my mind, the parallel is very clear with commercial lighter-than-air giants: even though there is an endless stream of con men who claim that their solution will beat all the previous failed attempts, and an apparently equally endless stream of people with more money than smarts who are willing to invest in tech they don't understand, the cycle always ends up the same way: oops...

Thanks, do you know about any other unbuilt GEVs?

 

[dan_inbox]

The list is huge: the Soviet Union, China, Germany, UK, etc. Heck, even Iran has built some.
Search "Ekranoplan" or "Wing in ground effect".

 

[A_Kid1234]

I normally view these thing from maintenance costs and fuel efficiency as well as practicality.

 

[Nik]

Beyond 'Fun Size', kin to speed-boats & hydrofoils, you have the problem of wave height.

Yes, such as the 'Caspian Sea Monster' could hop sand-banks and fishing boats but, like big sea-planes --Think 'Sunderland' or the JDF's sea-patrol-- GEVs need mild sea-state to land / take off. Worse, like big hovercraft, GEVs cannot fly above weather...

A proviso: Mega-GEVs would be okay, snag is they'd need nuclear power, be it fission or, safer, fusion. So, perhaps, early 22nd Century ??

Also, IIRC, DARPA propose the 'Liberty Lifter', a big, dual hull 'flying boat' that would be good to ~10,000 ft, yet significantly extend over-water range by flying at ~250 knots in 'ground effect'.

DARPA Wants to Revolutionize Amphibious Warfare By Developing An Entirely New Class of Flying Boat - The Debrief

DARPA announced it is moving forward with plans to develop an entirely new class of flying boat for use in amphibious military operations.

thedebrief.org

FWIW, IIRC, many 'Sunderland' sub-hunters were based at a Scottish loch, with convenient 'prevailing wind', plus a 'rode' that provided waves of convenient height to easily 'unstick', yet not big enough to damage...

Speaking of big hovercraft, our family once crossed English Channel on one of those big hover-ferries. The sea condition was deplorable. Route crossed Goodwin Sands. I repeatedly saw beige 'beach' along wave troughs, was very, very glad I was not a sailor beset on that notoriously lethal bank. Wave length and height were often enough to 'vent' air-cushion, which meant the entire craft tossed, rolled like any short ship in steep sea. Cabin conditions akin to wide-body jet meeting 'Clear Air Turbulence'. Ick. We often had air-gap between butt and seat. Even those passengers not sea-sick were 'significantly impaired'. We lost much of the time we'd saved over a ship-crossing by having to park-up, wait for our wits and guts to settle. Then, re-pack car to locate and replace everything that had been tossed around...

FWIW, the following year, the craft had been lengthened, significantly improving ride, and seat-belts fitted...

 

[Scott Kenny]

They're really only useful for limited niche situations, and those niches are too small to fund commercial development. And too costly to get a government to throw money at the problem beyond design studies.

 

[ILikeTanks]

They're really only useful for limited niche situations, and those niches are too small to fund commercial development. And too costly to get a government to throw money at the problem beyond design studies.

The maritime environment of tomorrow, with more frequent storms, icebergs and increasing amount of ships, would make GEV (hovercraft, WIG or compound) sound appealing. It would be impractical in a way to build more canals socially, so the ability to move equally good on any surface inherent to GEV would allow not taking detours but instead utilize the polar ice caps.


a small WIG like those of today would need to operate less than 1m from the surface. The air cushion generated is porportional to the ratio of wingspan/beam above ground, while the height of waves stays constant. This means that if you take the same WIG, but enlarge it into the scale of a cargo ship (1000 times the original weight, 10 times size in every axis), the operating height would become 10m. (edited)



Now imaging building a WIG displacing 10000 tons, able to operate within the cushion at 30 meters, this would become unaffected by storm.



So it should rather be noted that existing recreational WIGs in fact glide smoothly without rolling you'd typically experience or observe on a speedboat. I believe to that contraty to popular belief, the seakeeping of a WIG can actually be superior to that of displacement ships of similar size below a certain thereshold of waves, and this is scalable (in a large WIG that thereshold would be higher than the vast majority of sea conditions).

A large WIG with mean operating height above 10m would be ignoring most sea conditions below as long as the vessel keeps on moving. A WIG with same mass as a container ship would be capable of riding on an air cushion higher than 30m, a scale that would even allow operation above rural areas and tsunamis. Compare this to a container ship in today, and see the superior seakeeping (but not stopping) (however this is not improbable, large vehicles such as ships and airplanes don't stop normally on their voyages).

 

[Nik]

A caution: Arctic sea-ice may be thinning, year on year...

Arctic Sea Ice News and Analysis | Sea ice data updated daily with one-day lag

... but pressure ridges...

Pressure ridge (ice) - Wikipedia

en.wikipedia.org

...may still exceed a dozen metres height above 'mean surface'.

How such, in contrary wind, could affect a 'low flying' GEV is not something I'd care to experience. Worst case, the 'washboard' effect may destabilise altitude regulation...

Really big GEVs, of course, may 'ride' much higher than their 'midi' kin...