Day 4 of weird Russian Vertybirds. The Mi-32 heavy lift helicopter. Unbuilt.

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ElSquibbonator@reddit

This made a cameo in the second Neon Genesis Evangelion movie!

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Realistic_Country465@reddit

You mean the First Rebuild or the Second one? (Assuming we say EoE is the first) If so, you remember where

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Novogobo@reddit

that just wouldn't work. you need an even number of rotors to cancel one another out. it's stupid

the reason why 4 is so common is that you can do everything you need to do with just changing the speeds. if two on one side speed up it tilts and then moves in the directon of the tilt, if you speed up ones opposite each other and slow the ones on the other diagonal it rotates in place.

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Objective-Maize-8264@reddit

Yeah, i'am sure Mil design bureau at their height in the 70's and 80's. Having a reputation as the worlds premier helicopter design house knew no better then some fucking Redditor of all things.

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kevchink@reddit

It actually does work. Look up the La Cierva Air Horse, it was the first to apply this concept. The rotors are all tilted to provide thrust that counteracts the torque.

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wrongwayup@reddit

Did it “work” though? The first one crashed and they apparently stopped work on the second.

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Xivios@reddit

It flew for less than 20 hours, which is still far more than the 5 seconds they'd get if the anti-torque didn't work.

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Xivios@reddit

This tri-rotor was built and did work, though it never entered mass production. Anti-torque was by way of spinning all 3 the same direction but angling them all slightly such that the offset thrust countered the torque.

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T-701D-CC@reddit

Rotors don’t speed up or slow down to affect change in the aircraft’s pitch or yaw attitude

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EvidenceEuphoric6794@reddit

I thought that was how the chinook did it, how does it do it?

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Plump_Apparatus@reddit

The Ch-47 has a collective and a cyclic, just like most helicopters. See the wiki article. The Ch-47 requires no tail rotor as the rotors spin in opposite directions to cancel out the torque. The rotors themselves are linked together(cross connected) and cannot be individually adjusted for speed. Pushing forward on the stick(cyclic) changes the pitch of the rotors blade at a single point in each rotation. Adjusting the collective adjusts the pitch of the rotor blades at all points in rotation.

To pitch down the collective on the front rotor is decreased, and the collective on the rear rotor is increased. To turn in place in a hover the cyclic is used to pitch blades on the two rotors in opposite angles 180 degrees apart, I believe the rear cyclic is controlled by the foot pedals on the Chinook, but don't quote me on it. You can find the technical manual(TM) on google if you really want.

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T-701D-CC@reddit

I forgot what the term for it is but essentially the rotor disks tilt in opposite directions. Rotors can’t independently change speed because they’re mechanically linked

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EvidenceEuphoric6794@reddit

Oh yeah I know what you mean I forgot they did that aswell as throttle (probably because whenever I make them in ksp I'm too stupid to try and set them up right)

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T-701D-CC@reddit

Yea the term is called differential collective pitch, my roommate in flight-school was a chinook guy

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EvidenceEuphoric6794@reddit

Worked on them or just knew lots?

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T-701D-CC@reddit

He flies them, I fly Blackhawks

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Novogobo@reddit

on a 4 rotor drone they do.

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T-701D-CC@reddit

Drones aren’t helicopters 🤦🏻‍♂️

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Novogobo@reddit

so what? powered rotors produce torque on the airframe, that's all that matters, if that torque isn't balanced out it'll rotate the airframe.

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T-701D-CC@reddit

Yea but that’s not how they actually turn the airframe. But what do I know it’s not like I fly helicopters for a living

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Novogobo@reddit

ok you don't know. yes it's completely possible for the operator of a machine to not know how it works, i myself don't understand how microprocessors work yet here i am typing away on a computer keyboard.

on a conventional helicopter the tail rotor counteracts the torque that the main rotor puts on the airframe. varying the pitch on the blades attenuates how much torque on the airframe that counteracts it, that is what the pedals do. if you lose your tail rotor and continue to power the main rotor the entire aircraft will indeed start to spin out of control.

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T-701D-CC@reddit

Your whole comment is completely wrong. Go ahead and read TC 3-04.4 and learn yourself something

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andrea55TP@reddit

Both of you are right I think. You're correct in saying that you need to balance torque somehow, the other commenter is right saying that rotor speed is always constant for helicopters.

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HughJorgens@reddit (OP)

There isn't much info available. HERE is an article about it.

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thefactorygrows@reddit

Was this written by an AI? I think it may have been translated as I find parts of it hard to follow!

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speedyundeadhittite@reddit

Reading a bunch of Russian to English translations, I always imagine the Russian writing it completely drunk with illegally distilled Votka.

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Caerly@reddit

Just read Russian with AI translation
https://www.aviastar.org/helicopters_rus/mi-32.php

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No_Disaster_485@reddit

Cierva air horse

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LarryGSofFrmosa@reddit

How does it do Anti-Torque

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HughJorgens@reddit (OP)

Apparently you angle the rotor slightly so that they are each pushing slightly away from the center, something like that. Three separate but equal forces cancelling each other out.

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skythedragon64@reddit

How would it not spin completely out of control, considering there's only 3 rotors?

The few 3-rotor drones I saw had to do some special trickery for this.

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Broad_Parsnip7947@reddit

Just make each prop have a counter rotating second propellor

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okonom@reddit

I'm guessing each rotor mast would be mounted slightly inclined to approximately offset the rotor torque, and further yaw control would come from the cyclic tilting the rotor disc like in a Chinook.

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skythedragon64@reddit

Ah, didn't know it could work like that. That does make sense.

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dynamoterrordynastes@reddit

They could all be tilted in the same direction to cancel the torque.

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Xivios@reddit

The Cierva Airhorse mentioned in another reply was a built and functional tri-rotor, it worked by spinning all 3 rotors in the same direction, but angling them all so that they produced a little off-center thrust each, which countered the torque.

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thefactorygrows@reddit

Maybe each one is contra-rotating props? Or just the one in the "front" of the triangle. The two at the back could go opposite? But yeah, so many questions.

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skythedragon64@reddit

That would still require one of them having some weird tilt mechanism like those 3-rotor drones do, which would be rather mechanically complex.

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nmackey@reddit

I've built a few trirotors. They are my favorite to fly. But they have two counter rotating props up front and one on a tilt mechanism for yaw in the back on a servo. They fly great. I was going to build a 6 rotor tri in which the speed of rotation in the rear is what changes yaw.

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thefactorygrows@reddit

Not if they are coaxial contra rotating. The Soviets did just that in the Kamov ka-27

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skythedragon64@reddit

Ah. Doesn't look like it has that in this image tho

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GlockAF@reddit

Blown-air anti-torque

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getting_serious@reddit

It's why so many drones go for six rotors. And I'm guessing it's also why there are two turbines in each pod - wouldn't want one out of three rotors to stop. A hex maintains more of its cog envelope after failure.

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ozbikebuddy@reddit

Geez I could so see someone making a drone like this

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N33chy@reddit

Hack one prop off a quad copter and there you go!

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archwin@reddit

I mean, three rotor drones already exist.

It’s just a matter of dressing one up like this.

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CosmicPenguin@reddit

I remember seeing one, the trick is they have to be counter-rotating props because a drone with an uneven number of props will just spin in the air.

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wrongwayup@reddit

How do you lift anything with this? You’d need the load to be under the lift vector and there’s a big hole in the middle of the triangle where that lift vector would be.

Also with an odd number of rotors you’d need some sort of anti-torque system and I don’t see it.

This is fan art at best, I doubt it was ever a serious design

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Cthell@reddit

How do you lift anything with this

3 cables from the corners

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han_solex@reddit

Spinny dorito? Sir, this is a Wankel.

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Lirdon@reddit

This would have such a large center of mass threshold in any direction. Must be a great and stable flying crane.

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taisui@reddit

I don't know how it would balance the torque though, since the props are not in pairs.

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emurange205@reddit

I think you could run two of the rotors one direction and one rotor in the opposite direction at a higher speed.

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taisui@reddit

Technically yes, but don't they all use blade angle to adjust lift rather than rotational speed?

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emurange205@reddit

Yes, but by varying the rotor speed you could balance torque.

You would need a system that would compensate for changes in rotor speed by changing the angle of the rotor blade to maintain the appropriate amount of lift.

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Lirdon@reddit

You can do that, it’s not impossible. Maybe canting the rotors a few degrees to one side or the other.

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GlockAF@reddit

As long as there isn’t a dual engine failure at any one vertex. I can’t imagine that there would be interconnecting driveshafts between the pods, but…

Autorotations would be…weird

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Does Kerbal Space Program do rotorcraft?

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HughJorgens@reddit (OP)

So did I. I will give him a shout out tomorrow when I finish.

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