Igor Sikorsky Prize: Stock Helicopter Challenge

[Bluejayek]

This was my attempt:

It failed - the rotors couldn't even lift themselves upwards, let alone the entire craft. But heck, this is closer to a real helicopter than all the magic turbines I see being pumped out.

These aren't magic turbines. Magic turbines are where you are lifting with just the pods SAS or nothing.. these all have serious engine power.

How is your ship able to pivot those rotors anyways with stock parts? I didnt know that was possible.

Finally, please use spoilers

[RedDwarfIV]

These aren't magic turbines. Magic turbines are where you are lifting with just the pods SAS or nothing.. these all have serious engine power. How is your ship able to pivot those rotors anyways with stock parts? I didnt know that was possible.

Finally, please use spoilers

1 - Yes, they are magic turbines. Magic as in 'this could not work in real life because it takes advantage of KSP's inherent lack of proper wing lift physics'. How many real life helicopters do you know of that spin their pilots dizzy under normal operation? Small magic turbines need only their canards to fly once you get them started, but they still use engines to get them off the ground. Large ones are impossible without the engines - and what you are making are large magic turbines.

2 - The idea was that the rotors would have the decouplers, which are hollow inside [or at least the most likely to be], spin around the White Owl tail part. I put canards on the decouplers for lift [taking advantage of the magic turbine principle, I admit.] Then I put in a release mechanism and engines on the rotor parts.

Launching procedure would go:

/Engines start

/Full throttle

/Decouple rotors

/Rotors fly up and into their places, their lift holding them up against the tail parts.

/Liftoff

However, the rotors couldn't even get themselves off the ground, so I scrapped the entire plan and built a VTOL that can't be entered here.

3 - Done.

[Bluejayek]

1 - Yes, they are magic turbines. Magic as in 'this could not work in real life because it takes advantage of KSP's inherent lack of proper wing lift physics'. How many real life helicopters do you know of that spin their pilots dizzy under normal operation?

I agree spinning the pilot is a terrible idea, but that doesn't seem related to the comment about lift physics. Also, can you explain why (apart from the pilot thing) a principle of a spinning top with wings wouldn't actually lift in real life? (This is what a helicoptor has for its rotor after all...)

I might just be a bit confused as to the magic turbine phenomena.

[RedDwarfIV]

You can get a rotor to spin quite a lot more easily than an entire craft. With a helicopter, you need only one engine. For something like a real-life magic turbine you would need jet engines on either or several sides. Plus, the rotor for a magic turbine would have to be so much larger than a helicopter rotor to achieve the lift to make up for the craft's drag. And then you wonder if its even feasable to get such a large rotor up to lift speed without it shearing apart.

And then there's the question of what the hell do you do with a magic turbine that only goes up and down. If the Coléoptère C450 couldn't make the turn to level flight, a magic turbine as big as these certainly aren't going to.

The magic turbine phenomena is the fact that, to have the maneuverability effects neccesary, the cannards produce a disproportionate amount of floatiness compared to their size. This is because KSP doesn't run a physics simulation by the shape and size of a wing, it runs the physics simulation by what lift rating you give the part in its .cfg file. Thus you get a tiny wing that can cause a small craft to reach ludicrous speeds through nothing more than the cabin spinning.

Edited September 6, 2012 by RedDwarfIV

[iplop]

1 - Yes, they are magic turbines. Magic as in 'this could not work in real life because it takes advantage of KSP's inherent lack of proper wing lift physics'. How many real life helicopters do you know of that spin their pilots dizzy under normal operation? Small magic turbines need only their canards to fly once you get them started, but they still use engines to get them off the ground. Large ones are impossible without the engines - and what you are making are large magic turbines.

2 - The idea was that the rotors would have the decouplers, which are hollow inside [or at least the most likely to be], spin around the White Owl tail part. I put canards on the decouplers for lift [taking advantage of the magic turbine principle, I admit.] Then I put in a release mechanism and engines on the rotor parts.

Launching procedure would go:

/Engines start

/Full throttle

/Decouple rotors

/Rotors fly up and into their places, their lift holding them up against the tail parts.

/Liftoff

However, the rotors couldn't even get themselves off the ground, so I scrapped the entire plan and built a VTOL that can't be entered here.

3 - Done.

Complaining about realism while designing a helicopter that jettisons its rotors into cradles is a tad silly, no?

Proof that these designs aren't so unrealistic:

What you came up with is extremely interesting and I'd love to see it work but don't put down the other submissions just because yours didn't fly.

Edited September 6, 2012 by iplop

[Bluejayek]

Thank you for clarifying.

[RedDwarfIV]

It was the only way I could see to create a vehicle with a stable cockpit and rotors that span independantly from the rest of the craft. That it failed was not surprising.

Also, neither of those images show anything that could be upscaled to carry a person.

Also, I'm not putting down the submissions. I'm saying that they are not helicopters. If there were only a few submissions, I'd have said 'OP should say "Magic Turbines allowed"', but I don't think that's neccesary what with all four pages having only one exception, and that didn't fly.

Edited September 6, 2012 by RedDwarfIV

[MaverickSawyer]

Does

look interesting enough to you? Not stock (DamnedRobotics rototrons with altered .cfgs to make them more like a bearing, and a few bits and pieces from other packs), but still scary as hell. I call it "Jeb's Blender".

[Sbowyer28]

Red if you have something negative to say, Keep it yourself...

[RedDwarfIV]

There is a difference between magic turbines and helicopters. If the OP is happy to treat magic turbines as falling under the category of helicoptors, fine. I just thought it would be a lot more interesting for people to try and find a way of making an actual stock helicopter than taking a design which relies on a game physics quirk to fly and then making it bigger - a design that we already know works.

[VincentLaw]

To Appease RedDwarfIV, I have made a completely stock real helicopter with coaxial rotors that spin in opposite directions and independently of the fuselage. It took a lot of trial and error but is far from optimized. Also no canard or control surface "cheats" are used. Pictures and included craft file below:

[Bluejayek]

how do you make them spin independantly?

[RedDwarfIV]

Checking the .craft now. If it really is a co-axial independent-rotor helicopter, you will have effectively made the closest vehicle to the thread requirements so far - in that it would actually be a helicopter.

[RedDwarfIV]

Independant rotation confirmed. Though the SAS does not appear to have any unusual features, the rotors just, well, go around it.

Wait. DEVELOPMENT JUST IN. I'm guessing it was built in the VAB [with the possible exception of the craft's main body] where triple-symmetry could be used.

[Following information is based on evidence.] The rotors are fixed to a single structural pylon - which are notoriously bendy, so as the single pylon goes around in its spot, the rotors go with it. This assembley would have then been transferred back to the SPH for testing and such before being posted.

I disassembled it in the SPH to find that out. Ingenious design there.

[zekes]

Vincent, you are amazing

My only problem is control. I can't seem to control my choppers correctly. they will not remain upright.

Edited September 6, 2012 by zekes

[RedDwarfIV]

I was finding getting it to go in a straight line difficult, as if the contrarotating blades weren't doing their jobs at equal efficiency.

[zekes]

I find the parachutes help a bit, but the only way to really fly well is if the blades could move freely to find the right pitch angle....

Heres my heavy lifter.....

Edited September 7, 2012 by zekes

[VincentLaw]

Here is a smaller more stable version of my coaxial helicopter. I have not come up with a way to steer it, so it just hovers up and down (or crashes if you don't deploy the stabilization parachutes). I did calibrate it so that the fuselage does not rotate as much. As RedDwarfIV guessed, I did most of my building in the VAB. Also, if anyone is curious, I use decouplers in some places like the engine mounts because they are magic glue. Without them, the engines would fly off at regular RPM.

Edited September 7, 2012 by VincentLaw

[JackAz]

Man, that's awesome.

[zekes]

Well, I think we can say coaxial helis work, but we need some kind of control........

I'm thinking RCS. Would this work?

Im going to try to make a coaxial chopper out of my 3 bladed one. I think RCS will be adequate control for keeping the ship stable ( but surfaces on the fuselage will be necessarily).

Edited September 7, 2012 by zekes

[VincentLaw]

I have now achieved stable controlled flight. Basically I had to change the pod orientation so that the controls were on the same axis as the rotor. As discussed previously, the controls buttons are switched, so you pitch up with yaw left, and down with yaw right; roll left with pitch down, and right with pitch up. Remapping the keys is highly recommended. Unlike with the flying tops though, you can't trim the roll controls to increase thrust because the contra-rotating blades cancel each other out. So the only way to climb or descend is by altering the throttle instead. There is no effective yaw control, but the aerodynamics of the design cause the tail to try to point opposite the direction of motion, which is sufficient to steer anywhere you want to go. There is a quirk, at least on my computer, where this helicopter spontaneously explodes after about 3 minutes of cruising, so I will probably do a complete rebuild if I can't eliminate that.

(still stock)

Also, in my testing, RCS was not nearly strong enough to control a helicopter.

Edited September 8, 2012 by VincentLaw

[iplop]

I have now achieved stable controlled flight. Basically I had to change the pod orientation so that the controls were on the same axis as the rotor. As discussed previously, the controls buttons are switched, so you pitch up with yaw left, and down with yaw right; roll left with pitch down, and right with pitch up. Remapping the keys is highly recommended. Unlike with the flying tops though, you can't trim the roll controls to increase thrust because the contra-rotating blades cancel each other out. So the only way to climb or descend is by altering the throttle instead. There is no effective yaw control, but the aerodynamics of the design cause the tail to try to point opposite the direction of motion, which is sufficient to steer anywhere you want to go. There is a quirk, at least on my computer, where this helicopter spontaneously explodes after about 3 minutes of cruising, so I will probably do a complete rebuild if I can't eliminate that.

(still stock)

Also, in my testing, RCS was not nearly strong enough to control a helicopter.

It's official, you win the thread! ;D

[zekes]

I tried flying the kamov and It won't come off the ground.... Can you tell me how you did?

Edited September 8, 2012 by zekes

[VincentLaw]

It's a little heavy starting out, but full throttle should be enough. It is for me anyway. If that isn't good enough, you could try releasing the external drop tanks (stage 3). I'll check to make sure that is the correct version though. Also, I am interested to know if it explodes after 3 minutes of flight for anyone else. I am still working on a solution for that.

Edit: I just checked and that is the correct version. It does lift off the ground after about 6 seconds of full throttle starting out fully loaded. Just consider the drop tanks optional. If it still won't lift off the ground for you let me know.

Edit: As far as I can tell, the explosion problem is just associated with cruising in forward flight. I just tried hovering for 5 minutes and never exploded. There is probably some maximum speed you can fly forward without having to worry, but hopefully there is a way to raise that speed limit. The strange thing is that you can go fast for short periods of time. I just reached about 72 m/s in a dive before the forward motion caused the blades to intersect and destroy each other (which is not what is happening with the cruising explosion).

Edited September 8, 2012 by VincentLaw

[MaverickSawyer]

My Triebflugel encountered explosions in forward flight as well. I think it's due to weakening structural links, but I am not sure.