Al - Aviation Junkie

Can somebody please explain how on earth these guys are hovering nose down??? Like Scott Foster at ETOC this year where he kind of torque rolls stationary nose down..

All the rest of the stuff he does is understandable but hovering and keeping it in the hover..
Theres no prop-wash over the tail surfaces.. or is there a little from the prop sucking the air down?? I dont get it.. I dont see how his rudder an elevator has any effect..

STLPilot

My Feedback: (21)

It's basically the EXACT same principal as hovering a helicopter inverted. The only difference is that you have something more top heavy and needs much more control.

locoworks

sorry STLPilot but it is not like an inverted helicopter. a heli has cyclic control on the blades and therefore can push more one side of the 'prop' than the other to maintain a balance. the vpp only has pitch control and no cyclic. i think the model would need to be balanced as good as perfectly on the rotational axis of the prop, sort of like treating the airframe as a prop on a prop balancer with the prop shaft as the pivot. on that note, it may be possible to put a 3 servo ccpm setup on the front of a shocky and do away with the elevator and rudder servo's at the back end, or maybe use some mechanical mixing at the rear from the 3 ccpm servo's to control the rudder and elevator for extra control over the cyclic prop.

Al - Aviation Junkie

I agree, not that I've tryed(I'm still waiting for my VPP) but I don't think its anything like a heli... In fact I think these little buggers are more difficult to fly than a heli, or it could be the fact that I can fly heli's quite well an I'm still getting the feel for shockys...

I've watched the Scott Foster clip over and over and still can't see how he has such rudder and elevator authoroty when hovering nose down...

About the CCPM foamy... I think it would be way too intricate not to mention heavy... But who knows... we aready have VP Props on the damn things!!

Al - Aviation Junkie

I agree, not that I've tryed(I'm still waiting for my VPP) but I don't think its anything like a heli... In fact I think these little buggers are more difficult to fly than a heli, or it could be the fact that I can fly heli's quite well an I'm still getting the feel for shockys...

I've watched the Scott Foster clip over and over and still can't see how he has such rudder and elevator authoroty when hovering nose down...

About the CCPM foamy... I think it would be way too intricate not to mention heavy... But who knows... we aready have VP Props on the damn things!!

locoworks

i dont think it would be too intricate, it is essentially a direct drive flybarless micro heli top end with short blades mounted sideways ( in heli perspective )on the front of the shocky. it would need 3 servo's which are rudder , elevator and pitch. the same 3 that would be needed for VPP version along with aileron ofcourse. it would be a similar weight too albeit on the nose. i guess the battery would need to be behind the wing for CG purposes. give me a year and i may have a prototype? ( unless some unscrupulous lout pinches my idea from this thread ) LOL.

MKMotorsport

this might be completely off base- but my skill level has been advancing to the point ive been thinking about this more and more... weighted control surfaces?? combined with perfect balance as mentioned above?? am i onto something?

emnm79

My Feedback: (5)

I think what dion meant, was that one set of controls will be backwards, depending on your positioning, and that it is more difficult because the weight on top of the thrust always wants to pull the plane out of the hover, whereas in a normal hover, the weight always helps keep it in a hover being below the thrust...

The problem is that the airflow over the controls is a fraction of that of a normal hover/flight, but there is some, making it possible But I also think the weighted control surfaces might work, but hinder the balance/wingloading of the plane... There's only one way to find out

*gets ready to order the new vpp from HL*

c.meijer

Hi´ see you att ETOC
claes meijer/Sweden

TITANFLYER

Iv been flyn one for a while the main key to a nose down hover is to enter it exactly nose down. If you dont it will fall off to one side or the other. Vertical nose down rolls will help keep the nose straight down and extend the hover with a nice torque roll.

BytheBookie3

The faster the prop spins on the nose of the plane, the more centrifugal force, and thus more stability. If the plane is very light weight then he would need less pitch to keep the plane up and would be able to keep the blades almost flat, resulting in more rpm's and thus more stability. The "4d" pilot can thus make it look like a long controlled hover. The pilot can also fly the plane back a bit and then fly down again to adjust the plane straight during the temporary reverse and foward flight. It is not really possible at this time to control a planes surfaces during face down hovers because during those hovers there is a vacum aroung the tail. I would suggest for backwards flight though by trying to think of the plane as literally being already flying foward in the other direction except the throttleand rudder are reversed.

Hope this helps.[8D]

spec36

were can i find this video of scott ?

stryker_kyle

How do you guys setup the mixing for the prop pitch? Same as a heli?

jeffmeden

You guys forgot the other thing that makes a heli easier to hover, namely the tail rotor :-) Also, the problem with a cyclic on a VPP plane is that all of the torque to rotate the plane has to go through the center hub and then get transmitted to the plane, meaning there will be a LOT of lateral stress on the mount, and even then the effect will be dulled by how relatively short the prop is, and how far the prop is from the center of gravity (compared to a heli with a HUGE 'prop' and a short distance to CG). Not that it wouldn't be cool as hell ;-)

lthibault

Link to the Scott Foster video?

imfly1234

wow, 4d...and here i am working on my 3d. this stuff gets more and more interesting by the minute~

richardb9333

Hi guys , this is Donatas new arrow 4D at its best ! www.pauzuolis-rc.com/video/arrowmvppdp.wmv

Texas Instruments For Life

You guys are missing one important concept. Balance. If you were to place little weights in the control surfaces of the aircraft, you would be able to accuratly shift the aircrafts CG to keep it sitting nice and steady in its hover. Sure it would be hard to master, but it would work, and that is all that matters. I am sure that there is somebody out there who could master it.

ross_jsy

vid a couple of you guys where asking for [link=http://www.youtube.com/watch?v=1nfSdp07mj4&mode=related&search=]here[/link]