V-22 Osprey

[NitroDad]

I like building crazy stuff, so how about it is it possible to build one of these, would that be totally kick a#@ to see a V-22 Osprey flying at the local field? Dave whats your thoughts?
http://www.globalsecurity.org/military/systems/aircraft/v-22-pics.htm

[NitroDad]

I was thinkin a two engine setup might be a pain, and that a single engine that drives both rotors might work. Kind of like an axle in a car, except I think the blades would have to spin in oppisite directions to keep it stable, like the real thing. I have to confess though I have never flown a heli, but hey I'v got one, and this would be a good reason to learn right? Dave what u think?

[Dave Robelen]

Hi,
Since you asked I will toss in my $.02 worth. While at NASA I worked with the V-22 development program where we used tethered free flight models to develop all the necessary stability aids and control mixes. From what I saw, it would be very unlikely that we could use hobby grade equipment to do any thing similar. There is at least one modeler who has built a V-22 style heli, but the most it has done is fly in a limited vertical flight mode. It is the transition bit from vertical to horizontal flight that gets really messy. You are right on target with the cross-linked rotors and reverse rotation, these are found in the full scale machine. I would move on with the hobby heli, and watch for more sophisticated equipment to try a model V-22.
Good luck, Dave

[NitroDad]

Well I'm an adventuress person, so lets say hypothetically I tried this little undertaking, lets say I used two .30 sized units (my brain isn’t working) the main shafts, you know what I mean, would I need twice the engine? I think lots of power might be the key from vertical to horizontal flight, also is it possible to use multiple gyros?

[Dave Robelen]

Hi,
The engine size would be related to the weight of your machine. The smaller rotors are not quite as efficient as a pure helicopter, so you would need a little more power than a standard heli. Transitioning to horizontal flight actually reduces the required power, as the wings begin to pick up a bit of the work. A V22 model would need both collective and cyclic controls seperately on both rotors. It also will ned a controllable tail rotor in the horizontal plane. Along with this fun, it will also need aerodynamic controls to kick in as it transitions. Gyros for all three axis, and a computer programmed to integrate all this into the proper control codes for the various functions. All of the early NASA models flew on a tether on an arm that rotated to allow transition practice. This tether fed signals and power to the controls so that the computer did not have to be squeezed into the model early on. There was also an emergency winch that would pull the tether tight when the model got into trouble. Saved a lot of rebuilding. You may be able to do a Google search for the NASA papers on transitioning from vertical to horizontal. They would shed some light on your project.
Have fun, Dave

[NitroDad]

Are you serious about a computer? What about a pcm radio, I have a JR 783 (i think). I't a JR pcm for sure, I got it when a buddy needed some money, I gave him $40, he insisted I take his R\C stuff because his now exwife was getting rid of it alittle at a time, BS hu! I felt bad but I took it, I got a JR 8ch heli pcm, Hitech focus 4ch,2ch airtronics pistol grip radios, a concept .30 heli, two RC10's, and a Greatplanes Spitfire. By almeans I came out good, but I did tell him if he wants it back call me. Hell I tried to just give it to him 40 bucks!

[NitroDad]

Well, back to the prodject at hand, would i be able to covert an airplane prop or is that something I would have to make, or maybe some big ducted fans instead of heli parts, yea just have to make sure it is perfictly balanced to the center of the fans, that might even remove the need to having both turning oppisit directions? Maybe? Dave maybe I'm onto something here, or not them NASA guy have probly tried everything, but its worth a thought!

[Dave Robelen]

Hi,
The NASA guys went through all sorts of designs before settling on the V-22 as the most practical. The real need for the heli type rotors is to supply enough lift when in hover mode. Meanwhile, both rotors need to be controlled independently for steering and stability. When I reffered to a computer, I was talking about some serious computer power processing the signals inside the vehicle coming from gyros, accelerometers,control movements and such. There is a period during the transition from heli to airplane (or back) when these machines are unstable as all getout. Feeding all of the information through a computer that is programmed to make the right moves is necessary to get the job done. Why not start with a homemade heli, and work outward from there.
Cheers, Dave

[NitroDad]

Dave that sounds like serious stuff, theres got to be a redneck solution to it all, if there is a way, and I mess with it long enough I'll find it. Thats what I do solve problems.

[NitroDad]

Still thinkin, haven't givin up yet, ecspeically after I got to see one take off at Edwards AFB. Driving a truck has some bonuses.

[MPlante]

I am an actual V-22 mechanic. Have 8 years V-22 3 years ch-46. Currently working on fully functional model, electric config. Spent months researching and utilizing my resources to get an accurate blueprint and specs as well as making this happen within a reasonable budget. If there are questions pertaining to a design flaw that you may have please feel free to ask i will help the best i can. some information may not be disclosed however nothing in an rc model should be that extreme. Also building a website for my progress when things are together shall be posting in hopes to help others out.Good luck.