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Promethium

rudder and flight dynamics

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Hello allLooking for a bit of help with the rudder on my current project. The problem is when i put in say left rudder it results in a roll to the right where it should induce a roll to the left ????? i have been searching and tweaking to no avail and was hoping the answer is lurking in the collective minds on this forum.Any help on this would be much appreciatedCheersPaulPS here's a pic of the current projectBETA10.jpg

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Hello allLooking for a bit of help with the rudder on my current project. The problem is when i put in say left rudder it results in a roll to the right where it should induce a roll to the left ????? i have been searching and tweaking to no avail and was hoping the answer is lurking in the collective minds on this forum.Any help on this would be much appreciatedCheersPaulPS here's a pic of the current projectBETA10.jpg
Applying left rudder causes a yaw to the left. This is because left rudder generates a force to the right. This force acts behind the centre of gravity so it causes a yaw to the left. Also, because it is above the centre of gravity it causes a roll to the right.

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To expand on my previous post, one the aircraft begins to yaw to the left the right wing will move forward faster than the left wing. This will result in the lift on the right wing being greater than on the left wing. This will cause the aircraft to roll to the left.The rolling moment coefficient due to rudder deflection is sometimes called Cldeltar where deltar is rudder deflectionThe rolling moment coefficient due to yaw is sometimes called Clr and r is the yawIn both cases l is rolling moment.

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Hi mghI understand exactly what you are saying about the induced roll in the opposite direction and thanks for pointing me towards those values. The thing is the behavior of the real aircraft is such that a rudder defection to the left results in a roll to the left so i will do some tweaking and see what i come up with.Thanks again :)DiaThis has pretty much been a solo effort :( but to answer you question yes there is a 2D panel both standard ratio and wide screen as well as a 3D panel and (it gets better) a paint kit here are some picsBETA3.jpgBETA2.jpgBETA4.jpgHope you like it. By the way i used pics of G-AZOE for the profile shape of the model :)CheersPaul

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ok got the whole thing sorted now roll in the opposite direction, roll in the same direction both caused by the rudder the offending value was Cl_dr Roll Moment - Rudder = which needed to equal a negative number so a yaw to the left induces a roll to the left which can be found in record 1101 Primary Flight dynamics :) yyyyyyyaaaaaa thanks for the help

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Well, I see you've got the f*** lever just in the right place. It was extremely well placed for violently removing the skin from the knuckles of the left hand with absolutely no effort whatsoever. You learned very quickly....I remember the throttle and carb heat being on the left side of the panel, but maybe this was because I was flying the GAT rather than the AESL version. Underpowered, slow, stressed to +9 and -3 (better than an F4 Phantom!) and dead easy to flick around the sky. Just at this point I'm bitterly regretting never having taken any internal photos of the beast, but the paint kit will be extremely useful...! Hmm - I also put in a few hours on G-AWMI which was missing the spinner, a strip of insulation around the back of the canopy and also the insulation in the control column well. Somewhere there is a picture of me taxying MI and I'm well wrapped up in a hooded parka and wearing a heavy pair of gloves. Drafty and cold wasn't in it....-Dai

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(wee update) I think I've found the panel photo you are working from - it doesn't show the throttles. I've no idea if this pic will help but... You can't see the throttle knob but it should be white-and-handprint coloured.-Dai

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Hi Dia Thanks for the pic Tte Airtourer i am modeling off is owned by the the Liliydale aero club here in Melbourne Aus (which also happens to be the local airfield). i have over 200 photos of that particular aircraft as the club kindly gave me permission to crawl all over the thing :) the throttle control in that aircraft is as you see in the model but there is huge variation between the layouts of different Airtoures and it would be imposable to match them all :( as this plane goes with my Lilydale airfield scenery i wonted to be true to it. here's a pic of the real thingIMG_%38%300.JPGa link to the panel i am working from (this is a combination of a couple of pics)PanelAnd a pic of the night lighting (thanks in no small part to these forums thanks guys)3DNIGHT.jpgEnjoyand thanks again for all the help so far it probably wont be the last time i ask something :( PaulPS If people are interested in this project I might make a proper post chronicling its development there is already something like that over at the Vista Australis forums :)

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I blame you for me wasting an hour+ looking up Airtourers on the net yesterday... :( The latest version of the CT4 made me grin widely - an Airtourer fitted with an all-glass cockpit - what a strange concept! You're right about cockpit variation though; I knew about it but even so, the amount of variation took me by surprise. I did (finally) manage to turn up a couple of cockpit photos from the era I was flying them (mid-Seventies), so with your permission I'd like to mangle your cockpit when it's finally released? And yes - what's the link to the Aussie site?-Dai

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Hey oI take no responsibility if you have a thing for very nice aircraft :( the Link to the Aussie is www.vistaoz.org/ you need to register to view the forums and the thread in Evolution of a Victa Airtourer as for the cockpit if you wont to do a custom 2D be my guest although most of the gauges in my panel are interconnected and wont work without the others so be warned :D have funPaul

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