"Sailing Aircraft"

[Tophe]

in the French teenage magazine "MonQuotidien" #4 269.

"Aircraft manufacturers have unveiled aircraft that will fly before 2030 (...) The 'Sailing Aircraft' will be able to cruise on sea and in the sky. This 4-seat boat will be convertible into airplane. In flight, wings will be set horizontal. After landing on water, wings will come back vertical. One can even open the canopy to have wind in the hair."

 

[mz]

Those bearings and the actuators have to be pretty hefty. Also it will tip over on water unless it has a paravane.

 

[Avimimus]

I'd hate to have to pilot that on sea or in the air if the winds picked up. I wonder what margin it has?

On the other hand, I could see a semi-submersible conventional seaplane that could wait for bad weather to improve before attempting a takeoff (although strength might create weight issues).

 

[Arjen]

As a sailing boat, with sails that big it would need a substantial keel or equally substantial leaboards/centreboards/daggerboards. A properly weighted keel would be out of the question - no flying with that much weight - so boards it is, and I can't see them. And some outriggers. Big ones. IF it will sail, it won't fly. IF it will fly (a big if, considering those hinges and actuators), it won't sail.

Nice picture though.

 

[AeroFranz]

wasn't there an inter-wars German flying boat that had a standard equipment of masts and sails?

 

[Arjen]

Dornier Wal (filed under "Flying boat, inappropriate use of")

 

[Tophe]

And there are also patents of actual flying sailboats:
http://www.google.com/patents?id=kMuAAAAAEBAJ&printsec=drawing&zoom=4#v=onepage&q&f=false
http://www.google.com/patents?id=mTstAAAAEBAJ&printsec=drawing&zoom=4#v=onepage&q&f=false

 

[Arjen]

*Very* interesting.

 

[Avimimus]

I can see the Dornier making sense (in light of potentially unreliable engines). I can't actually think of a good reason for the recreational designs, though.

 

[Arjen]

I don't expect they'll ever be built, but they look more realistic than the thing from the magazine. Sort of an intellectual exercise.

 

[Jemiba]

In the case of the Dornier Wal, the sail was just a makeshift solution AFAIK,
but the Rohrbach Ro III, roughly contemporary to the Dornier Wal actually was
delivered with jury rig.
(Photo from F.Gütschow "Die Deutschen Flugboote")

 

[Matej]

in the French teenage magazine "MonQuotidien" #4 269.

"Aircraft manufacturers have unveiled aircraft that will fly before 2030 (...) The 'Sailing Aircraft' will be able to cruise on sea and in the sky. This 4-seat boat will be convertible into airplane. In flight, wings will be set horizontal. After landing on water, wings will come back vertical. One can even open the canopy to have wind in the hair."

Identified as the creation of the designer Yelken Octuri. http://www.octuri.com/en/aircraft-of-the-future/sailing-aircraft/

 

[Tophe]

Thanks for this dreamy link...

 

[Arjen]

@jemiba's Ro III: Much, much better as a sailing boat than the Wal.

 

[Jemiba]

@jemiba's Ro III: Much, much better as a sailing boat than the Wal.

With its configuration it could well behave similar to one of those otrigger canoes from
the South Seas. Actually, this rig was developed by Adolf Rohrbach himself and the quite
elaborated realization seems not to be just for emergencies, I think.
Another photo from http://www.histaviation.com/Rohrbach.html

 

[hesham]

Hi,


the same concept from Mr. Domenjoz;


https://retrorambling.wordpress.com/category/aviation/

 

[Jemiba]

It really looks, as it was intended to be driven by sail in the air ! Judging the direction
of the wind needed for propulsion and the needed speed for staying in the air, it
seems to me, that some physical laws were overlooked by the inventor !

 

[Stargazer]

It really looks, as it was intended to be driven by sail in the air ! Judging the direction
of the wind needed for propulsion and the needed speed for staying in the air, it
seems to me, that some physical laws were overlooked by the inventor !

If I tell you that his name "Demenjoz" is pronounced exactly like "Demain j'ose !" (tomorrow, I dare!) it makes you wonder... :

 

[_Del_]

As a sailing boat, with sails that big it would need a substantial keel or equally substantial leaboards/centreboards/daggerboards.

I wonder if you couldn't use manage to use one wing as a keel and one wing as a sail. Not in that design, but speaking generally.

And there are also patents of actual flying sailboats:
http://www.google.com/patents?id=kMuAAAAAEBAJ&printsec=drawing&zoom=4#v=onepage&q&f=false
http://www.google.com/patents?id=mTstAAAAEBAJ&printsec=drawing&zoom=4#v=onepage&q&f=false

Those are rather clever also.

Never given the idea any thought. Very interesting thread!

 

[joncarrfarrelly]

Sails don't work for airborne propulsion, didn't work on balloons or dirigibles,
definitely wouldn't work on an airplane. Also he didn't have enough hull for it
to be a viable boat.

Remove the wings and it would make an OK salt-flats/dry lake runner or iceboat. ;D

 

[Avimimus]

Well there are ways to theoretically build wind powered dirigibles (probably small, 'planktonic', unmanned observation drones which have an efficient buoyancy adjustment system and can pick an altitude with favourable wind direction).


Btw. Would it be appropriate to discuss actual cases of disabled seaplanes/floatplanes adrift in this thread? It is important context for why sails (or other forms of ditched propulsion) were so desired.

 

[hesham]

the same concept from Mr. Domenjoz;

https://retrorambling.wordpress.com/category/aviation/

Hi,

http://www.retroplane.net/forum/files/domenjoz_sail_glider_159.pdf

 

[riggerrob]

Dear avimimus,
There are a few experimental submarines that change buoyancy to dive forwards or climb forwards. They have substantial horizontal "wings."
Military submarines have trim vanes to allow them to fine adjust depth without changing buoyancy. Dive/trim vanes work the same as rear elevators on airplanes.

Theoretically, you could build a dirigible that achieves forwards speed simply by varying buoyancy. Reducing buoyancy in the bow (vent lifting gas or fill a ballute with air or slide ballast forward) would cause the airplane to dive forwards. This method is slow and cumbersome, so dirigibles only use it to supplement propellers and tail surfaces.

 

[riggerrob]

And there are also patents of actual flying sailboats:

US7252264B2 - Flying sailboat - Google Patents

A vehicle adapted for airborne flight and waterborne sailing has a fuselage ( 20 ) with left and right wings ( 52, 54 ) that pivot independently about a respective longitudinal axis from a generally horizontal orientation for flight to a generally vertical orientation to provide wind-driven...

www.google.com

US3987982A - Wind-powered flying boat - Google Patents

A water-based sailing vehicle that is able to accelerate from rest under wind power, become airborne, and fly above the water. At low speeds, the vehicle performs as a displacement sailboat. At higher speeds, the weight of the vehicle is supported by a combination of hydrodynamic lift from the...

www.google.com

DearTophe,
The proa on the bottom makes the most sense as it vaguely resembles some of the ultra-high speed sailboats designed to exceed speed records. As long as you keep all the engine and crew weight in the main hull, they are less likely to tip over (pole end). They even use hydrofoils to reduce water-resistance. Keep in mind that record-setting sail-boats are strictly single-mission and can only sail in shallow waves.
Because record-setting sailboats are single-ended, they are even more difficult to tack than traditional Polynesian proas.

 

[Peripatetica]

the same concept from Mr. Domenjoz;

https://retrorambling.wordpress.com/category/aviation/

Hi,

http://www.retroplane.net/forum/files/domenjoz_sail_glider_159.pdf

Domenjoz was an odd one, and there's all sorts of misinformation about him out there on the web. I've found his surname spelled at least four different ways, and of course he was not, as many contemporary newspaper accounts claimed, the first pilot to loop-the-loop in North America. He did circle the Statue of Liberty, though, and toured internationally. His Blériot XI is at the Smithsonian's Udvar-Hazy in Virginia.

He said that he grew up sailing on Lake Geneva and he definitely was one of the earliest - as in well pre-WWI - barnstormers. He was also an instructor at Blériot's flight school in Pau, hence the very Blériot-influenced fuselage on the sailing glider. So he should have known that the thing would not work, yet he and a partner took out patents for it in both France (as posted in part above) and England, and he later took out a U.S. patent in his name alone (also posted in part above - thanks!). There are at least two extant pieces of film footage of Domenjoz "flying" it at Old Orchard Beach (OOB), Maine, United States in 1929, but in both instances the aircraft was being towed by a car. One piece of film shows it airborne with sails rigged; in the other it's just the glider aloft, with no masts, let alone sails. OOB at the time had a very long stretch of hard-packed sand, like Daytona Beach (Florida), and because of that coupled with how far east it is, there were many transatlantic flight attempts from there in the late 20s.

I tried to find previous references to OOB on this forum & didn't see much, but apologies if I'm repeating known info.

If you ever want to see the actual Domenjoz sailing glider (or "gloop", for "glider" + "sloop", as it was nicknamed at the time), it survives, still in Maine, on static display at owlshead.org. It has been fully restored and really is a beautiful oddity. You should see the cockpit - you'd need four arms and a trained monkey to work all the controls. I have a lot more info on it and Domenjoz himself, but won't bore you unless there's interest.

 

[Richard N]

The most advanced sailboats are the America's Cup AC 75s competing in New Zealand January 2021 for the finals in March. In winds above 8 knots they fly on their foils at speeds up to 50 knots.

A good technical description of the boats:

View: https://youtu.be/sjs76uHEqeM?t=812


One of the races:

View: https://youtu.be/2EeTR9U4F98


More info in this thread: https://www.secretprojects.co.uk/threads/americas-cup-flying-boats-in-new-zealand-2020.36134/

 

[hesham]

Mr. John Domenjoz.

Les Ailes : journal hebdomadaire de la locomotion aérienne / directeur, rédacteur en chef, Georges Houard | 1925-04-09 | Gallica