Ringplan - possibly the future of aviation

In 1936, in the USSR, it was proposed to create a "ringplane" by a student-engineer of the Moscow Aviation Institute Sukhanov.



The project was presented in the thesis. They became interested in this proposal, and the idea of ​​a ring-plane fighter was discussed at the scientific and technical council of TsAGI. But the pre-war situation prevented its implementation. At the beginning of 1942, Sukhanov himself created a working model of his apparatus, which confirmed all the positive characteristics. However, due to the war, the project was never sufficiently researched and did not reach prototypes, let alone mass production.

In the same war, the idea of ​​a ring wing was developed by the designer Ernst Heinkel among the Germans. His fighter "Lerche" (or "Skylark") had a 9-sided wing.



But in the end there were not enough funds for this car, and the project was closed. In 1959, the French entered the stage with a new design of the ringplane. And they brought the work to a real prototype in metal. You may have heard of the SNECMA C-450 Coleoptere? This machine is a vertical take-off, which, after climb, was supposed to go into level flight.



However, the S-450 could fly, unfortunately, also only vertically. During the transition to level flight, it lost stability and fell. That almost cost the pilot's life. So this project was closed.

It is perhaps worth mentioning that at the beginning of the 20th century, namely in 1909, also the French engineer Zhivodan assembled one of the most unusual structures of an airplane with an annular wing. Two annular wings were located in the nose and tail of the aircraft, and the pilot was in the middle. But this device did not take off either.



In 1988, Soviet engineer Arkady Narushevich and pilot Anatoly Gushchin, in the course of replacing the outdated An-2 aircraft, which was sensitive to lateral wind gusts, began to build an aircraft with an annular wing. But with an oval, not circular shape.

Small models were built that flew quite well. The team then procured materials and built the first oval wing. But this was followed by the collapse of the USSR, and even those funds that were initially allocated were withdrawn. So the team was left without funding. But it was still far from the end.



In 1998, Gushchin and Naskidyants, as well as other pilots, persuaded Narushevich to continue working on the plane. Plus, a private company appeared, which became interested in the project and allocated funding. The team rebuilt the wing, assembled the fuselage. We had to take the landing gear from the Mi-1 helicopter, and the instrument panel from the An-2. Otherwise, everything was done in the full sense "from scratch". The fuselage was counted on for two pilots and three passengers, or two pilots and agricultural cargo.

By 2004, the work was completed and testing began. The aircraft immediately showed curious good characteristics. It was practically "transparent", so to speak, before the crosswind. That is, I did not feel gusts if they did not exceed 13 m / s (which is almost 47 km / h). It could take off from a 150-meter strip (An-2 required 180 meters). But all these advantages paled over one more - the ratio of the payload and the total weight of the equipped aircraft. It turned out to be equal to 0.45. For An-2, this coefficient is not more than 0.3. That is, almost half of the mass of the ringplane is a payload.




Aircraft advantages:
The first is a lower take-off speed and a shorter runway.
The second is the high ratio of the mass of the cargo to the total mass of the equipped aircraft.
The third is the increased strength of the annular wing in comparison with the usual one, as well as its lower weight.
Fourth, there is a lot of lift at the same swing.
Fifth, this is another aerodynamic model for generating lift that opens up new horizons.

Various designs of other models are being developed on the basis of the existing aircraft.




Thanks.

a reply to: RussianTroll

Great post!!

I have not seen one before so thanks for raising this, I am looking forward to different aircraft designs to overcome our pollution, cost, noise and other challenges.

A current Russian project that might have some possibilities. 2025: Aero-platforms, ‘Saucers’ Will Carry Cargoes up to 600 Tons youtu.be...

The new heavy-duty airship projects are being actively developed in the Russia. Such innovative airships in foreseeable future will appear in the sky to surprise mankind by their ability to transport of tens and even hundreds of tons of payload, and fly in winds up to 35 m / s, and even worst on speed 100-250 km / h on the range 5,000 km and even more. Their project speed is 100 to 250 km / h.

Despite the popularization of heavier than air drones, the interest in aerostatic manned and unmanned systems continues to grow. A behind-the-scene race is unveiling in the world to design and implement the heavy-duty transport airships. The reasons are obvious: the economic crisis, the growing demand for heavy air transport traffic, the shortage of transport aviation fleet.

www.veteranstoday.com...

a reply to: RussianTroll

Interesting aircraft. I'm aware of most of these, but a couple are new to me. Thanks.

In terms of US equivalents - I'm aware of the Hiller VXT-8 Coleopter Concept and my own personal favorite - the Convair Model 49 (from 1967).
Here's a couple of links on the Model 49 - with it's tilting cockpit and interestingly mounted weapons.
www.aviastar.org...
www.diseno-art.com...

They are reinventing the biplane? So, everything old is new again? When do the air ship cruise liners come back into fashion?

a reply to: beyondknowledge

www.rusaviainsider.com...

I used to make the round paper flying tube out of a sheet of paper when I was a kid.

originally posted by: 38181
a reply to: beyondknowledge

www.rusaviainsider.com...

I used to make the round paper flying tube out of a sheet of paper when I was a kid.

The problem is the same as the old biplanes, there is increased drag inharent in the design.

The circle wing has only about 50% of the wing surface producing lift but the full weight and drag of the ring is still there. The oval design is better but still at only about 80% lift. You are basically carrying around 20% extra weight in those wings and all the drag associated with it and getting no benifit from that material.

The biplane was abandoned because monoplains are more fuel efficient or faster depending on the design. They are still a novelty but have you seen a biplane airliner recently?

originally posted by: RussianTroll
Aircraft advantages:
The first is a lower take-off speed and a shorter runway.
The second is the high ratio of the mass of the cargo to the total mass of the equipped aircraft.
The third is the increased strength of the annular wing in comparison with the usual one, as well as its lower weight.
Fourth, there is a lot of lift at the same swing.
Fifth, this is another aerodynamic model for generating lift that opens up new horizons.

Various designs of other models are being developed on the basis of the existing aircraft.

A lot of those advantages sound plausible.
One supporting factor even on conventional wings are cases where we see winglets being added to reduce the drag of wingtip vortices.

Perhaps the ring wings eliminate the wingtip vortices completely since technically a ring wing doesn't have any wingtips?

One claim I'm not sure of is the "lower weight", and of course the curved wings could complicate more conventional flatter control surfaces on flatter wings. So there may be negative cost impacts for making curved control surfaces, and possibly other negative cost and other impacts not mentioned (Making a ring wing could be more costly in general than making flat wings), but it's an interesting concept.

a reply to: beyondknowledge

Sorry, but I don't speak to Grays! Ain't no gray aliens welcome 'round these parts, I think it's high time you took your gray butt back to Planet Your Anus, and leave us good folk to our oval thingies.

Yep...they call me...The Alienist

a reply to: Arbitrageur

The more mass an airplane lifts into the air, the longer (and elongated) a conventional flat wing should be. But the wing "hangs" under its own weight in the parking lot, engines are often mounted on it. This weight is partially unloaded in flight, but the load appears in the opposite direction, since the wing, on which the lift acts, "holds" the aircraft. As a result, the wing must have a high degree of both strength and rigidity, and this is solved to a certain extent by an increase in the structural mass. Plus there is a need to resist fluctuations (remember "flutter").

For an annular oval wing, this problem is solved by the fact that it is, as it were, "closed" to itself, there are no "ends" that can oscillate. It is probably difficult to explain this in a nutshell. But a regular wing and an oval wing are like a beam and a truss of the same mass. The second will be stronger than the first.

Another point of benefit of a ringplane is associated with the fact that a conventional wing has an "inductance". When air flows, vortices are created at the ends of the wings from bottom to top. For their formation, the energy of the aircraft is consumed, so that energy losses occur, and efficiency decreases. In a ringplane, there is nowhere for air to flow in this sense, since there are simply no "wing tips".

Another feature of this particular ringplane is that the fuselage is located between the upper and lower plane of the wing, being attached to struts and suspensions. Thus, the entire wing works "in full", there is no place where it connects to the fuselage, where the air flow does not blow over it.

Further. The top and bottom "planes", although rounded, function like a conventional wing. But there is a big difference. The flow inside the ring, even at small angles of attack, produces a significant vertical component of the momentum, that is, the air "flies" backward, but also downward, and this creates an additional impulse of lift. So the lifting force of a ringplane is greater than that of a biplane of the same range.

Stalling of the flow on the upper surface of the upper wing is also possible, but the general annular air flow, as it were, entrains the air from the upper plane, and this increases the stability of the aircraft. Ring wings provide the ability to increase the angle of attack up to 50 degrees!

The ability to fly at such huge angles of attack, plus the flow deflection effect, makes it possible to fly at extremely low speeds without the use of flaps and slats. This means that the plane can confidently take off and land on short stripes.

After experimenting with the oval wing, Grechikhin, Ph.D. in physics and mathematics, who works in the ringplane group, believes that ordinary flat wings may soon be a thing of the past. Moreover, the oval wing is 2 times lighter with the same lift.

a reply to: beyondknowledge

Exactly what I was coming here to say. The only real benefit of the design is that it does remove wingtip vortices, which cause wake turbulence and induced drag. However, spheroid winglets do have potential for doing that as well.

The latest proposed modification has been derived from previous work on a “double-winglet, closed-loop design,” said Clark. Dubbed “spiroid winglets,” the technology was developed by former Boeing aerodynamics chief Dr. Louis Gratzer, who claimed it eliminates concentrated wingtip vortices, which account for nearly half of the induced drag generated during cruise.

Technology reshaping Aviation Partners’ winglets May 2006

Aviation Partners of Seattle flew a Dassault Falcon 50 testbed outfitted with new experimental "spiroid" winglets to Oshkosh, Wis., for the EAA AirVenture airshow last week. The new design is part of a NASA-funded research program aimed at boosting efficiency.

AVIATION PARTNERS TESTS 'SPIROID' WINGLETS ON FALCON 50

Another drawback of the annular wing design is the blocked view, especially for light aircraft with wings that have their circumference around the cockpit. I suppose that a clear laminate could be used, but I would imagine the transition in materials would create weak points in the wing design.

a reply to: RussianTroll

Great post!

If one searches for "annular wing," one finds beaucoup hits. As the OP points out, it's been tried many times and in spite of that we still don't see any practical annular wing aircraft in private, corporate, or government hands. I'm not trying to be That Guy, but there must be a reason why.

a reply to: RussianTroll

Definitely looks like something Russia would sink a lot of money into.

originally posted by: cmdrkeenkid
Technology reshaping Aviation Partners’ winglets May 2006

AVIATION PARTNERS TESTS 'SPIROID' WINGLETS ON FALCON 50

They announced those tests back in 2006 and 2010, but I didn't have any luck searching for the results of the tests, do you know what they found?

originally posted by: Cohen the Barbarian
If one searches for "annular wing," one finds beaucoup hits. As the OP points out, it's been tried many times and in spite of that we still don't see any practical annular wing aircraft in private, corporate, or government hands. I'm not trying to be That Guy, but there must be a reason why.

I was thinking the same thing. Part of the reason might be explained here:

originally posted by: beyondknowledge
The problem is the same as the old biplanes, there is increased drag inharent in the design.

The circle wing has only about 50% of the wing surface producing lift but the full weight and drag of the ring is still there. The oval design is better but still at only about 80% lift. You are basically carrying around 20% extra weight in those wings and all the drag associated with it and getting no benifit from that material.

The biplane was abandoned because monoplains are more fuel efficient or faster depending on the design. They are still a novelty but have you seen a biplane airliner recently?

a reply to: 38181
Cool! I had a Wham-O Turbo Tube!

a reply to: Arbitrageur

This looks like maybe it's the results from the study mentioned in the articles I linked to previously.

A CFD Analysis of Wingtip Devices to Improve Lift and Drag Characteristics of Aircraft Wing Southeast Asia Workshop on Aerospace Engineering (SAWAE 2019)

For the analysis of the various wing tip devices the three- dimensional wing is incorporated with the spiroid winglet, blended winglet, wingtip fence and a mini-winglet. The CFD analysis for the wing designs is carried out for the take-off and landing phases of an aircraft’s flight because the effect of vortices is the highest during these flight phases. The angles of attack range from 0° to 20°...

The comparison of the various spiroid winglet designs reveal that the design configuration of the spiroid winglet with parallelogram produced less drag and more lift. Hence the blended winglet with 30° cant angle can be regarded as the most suitable winglet as it produces the highest rise in lift coefficient and a comparable decrease in drag coefficient.

The results show some very specific flight profiles where the spiroid winglet is marginally superior, but looks like the 30 degree winglet is still better for lift and drag overall. Per their website they are still studying the spiroid style, but don't have much to say about it other than that.

a reply to: cmdrkeenkid
Thanks for the links.
The blended winglet designs seem to be what are getting used, so I suspect there is more testing showing they produce good results.

It's interesting they are still testing the spiroid winglets but I have yet to see those in use.

a reply to: Arbitrageur

Probably keeping the test going to keep the Federal funds running in, if nothing else.

a reply to: RussianTroll

think longand pointy with pretty dramatic wings and a cruising speed of at least Mach 1.


if we can build intercontinental bomber that can go over 3 times the speed of sound it would seem like we could convert that tech to a civilian or even military transports

be kind of a pricy ticket but people drop over 50 grand on flights on Emerits all the time


ETA: the quite boom demonstrator from nasa also had a ovid wing