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Guest jonpoint

GeeBee update (renewed)

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Hi Folks,Since this disappeared from the list I thought I'd restart it ;)I have been doing some more playing but I've been to busy to achieve much yet. I would like more input on the flight model changes as I really have my hands full with everything else :-(My suggestion is that we nominate a few people to be the modifiers/testers then post the different flight models, try them out and vote on them. I'm pretty useless here - I can modify all I want but there ARE others better qualified to try out the changes :-)I'd like to nominate Ansgar, Hans Petter, GeeBee Jim (if he can lay off the nitro pills long enough...) and invite anyone else (who thinks they know how a plane SHOULD fly) to join. By documenting changes as we go and also by trying out each other's models we can eventually vote for the 'best' model. The model chosen will be used in the 'beta' GeeBee R2.Good idea (or shoot me down...)?Jon Point*************************(effyouthree@hotmail.com)*************************

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Good idea! I'll be honored to help test this aircraft but I'm not too familiar with this old taildragger. This is a very special aircraft and GeeBee Jim probably is the only forum member being able to advise you.However, if you know the "benchmark speeds" -- V rotate, stall, Vmax etcwe could all test whether it flies according to specs. Then, if it flies at less than the proper take-off speed you may reduce wing area / add weight and vice versa. If it's able to fly faster than the real GeeBee you may add some drag and vice versa. In short, the best way to test this (or any other) aircraft is to compare it to published specs. best regards,Hans Petter

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Sign me up Jon, glad to help. I continue to play with it, and find it a real kick. Control functions in the air are just fine, and landing is just a tad more difficult then the Mustang, as it should be. Spreading the mains a bit should make it just right. Takeoffs remain unpredictable, and fighting that mysterious, incorrect right hand torque, results in a lot of wing dragging. I like the top speed where it is, but the engine needs to vibrate the craft more.I enjoy crosscountry airport hopping, but as you can expect, all strips will not accommodate it.GeeBeeJim@aol.com

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Just checked Delmars book, and it says that his replica R-2 did just about 300 MPH, which I think is just about where you have it. For what it's worth.Jim

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Jim,Glad to have you aboard - I knew you'd be interested anyway :-beerchug"..the engine needs to vibrate the craft more."Well, all things being equal, things should rattle a bit more with the new soundfiles! I ended up using some of the recorded ones after editing out some of the sounds that made the loops sound silly. They are sorta more 'brutal' than the preview ones. After all, the GeeBee doesn't have a muffler - or even an exhaust manifold, just 9 pipes sticking straight out of the cylinders and peeking out from under the cowl! I tried very hard to capture that feel, especially at idle. Above 33% throttle, the prop wind noise suddenly picks up and sorta drowns the exhaust sound a bit. The engine sounds ARE louder now but I've left the wind noise where it is because it's got lotsa wires and they'd make a racket - especially at 200+KTS, er sorry - MPH ;)With luck I'll post the files and a Resviewer script to you tomorrow. :-hahJon Point*************************(effyouthree@hotmail.com)*************************

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Hi Jon,as I see everything is OK and coming forward here. If you need my support... a short mail and I

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Yes Jon, crazy right hand torque must be wash related. I have noticed that as tail rises, and the left wing begins to dip, a quick blip of left rudder will reverse the roll action. And the sound, I love the prop noise the best. Now when I buzz Sequim Valley, I can see the people running out of their houses, looking skyward while covering their ears. ( Well .... I can almost see them. )Gotta run to the Doc's now, I think that I need my medication changed.Jim

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Jim and others,Yep, I turned it all off last night - every bit of effect. Then I turned 'engine torque' off and tried it out 'straight' to see what happened. By golly, it went straight :-) Still needed some up-elevator to get off the ground but once in the air she went straight... up. Climbs well when you're not using the ailerons to keep it straight. Goes even better - 244kts level flight at 3kft! Seem to be wasting a lot of power with that 'issue'.What this leaves me with is, if we want opposite torque, we will have to switch 'engine torque' off and do it with wash effects. As soon as you turn the torque on, you must compensate with wash and that gets tricky because wash isn't a stable and repeatable effect - it's affected by airspeed AND prop speed. Simply revving the engine at low ground or airspeed doesn't do much, whereas the torque effect should be quite high. Conversly, at high airspeeds, pulling the revs back should cause a slight effect but the 'wash' seems to fall off exponentially, putting the plane into a spin :-grrThe existing flight models attempt to compensate for the opposite torque using wash and it quite obviously doesn't work. Hence the instability when applying or cutting power. This is also why it likes to 'flip' on the runway during takeoff - too much torque, too much wash effect. Once the speed builds a bit, the airfoil effects come in and... :-erksI'd really like to know how to reverse the torque effect. I've stuck a (-) in front of every variable I can find but no luck at all :-( Any ideas welcome!Jim,I'm glad you like the new sounds, they're actually mixed from 3 different sources now, so at any time you may hear a DC3, a Beaver or even a (the) real GeeBee. The 'run' sound is DC3/Beaver!Thanks for the comments and support!" ..skyward while covering their ears. ( Well .... I can almost see them. )Gotta run to the Doc's now, I think that I need my medication changed."Dunno about that! If your medication gets PEOPLE running out of houses, maybe we should arrange downloadable prescriptions for the racing package :-beerchugJon Point*************************(effyouthree@hotmail.com)*************************

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>>Jim, >>I'm glad you like the new sounds, they're actually mixed >from 3 different sources now, so at any time you may hear a >DC3, a Beaver or even a (the) real GeeBee. The 'run' sound >is DC3/Beaver! >Jon: Maybe just a tad louder ? He, he, he. Just love that ticking at idle, and the prop thrashing at the top end.Ya got it nailed buddy ! ! !

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Please try to off-set the engine a tad to limit excessive torque. Modern aircraft actually have off-set engine(s). Torque SHOULD vary with speed, being most pronounced when revving up at low speeds.Hans Petter

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Hans Petter,You are correct that torque should vary with changes in revs. This can ONLY be done by invoking 'engine torque'. All other wash effects are engine speed or airspeed related, which is not the same!I was going to try offsetting the engine next however, as I mentioned above, as soon as you invoke 'engine torque', we have the wrong direction. I am beginning to think that we may have to live with the (wrong) direction. What I am going to try is to make everything work 'the wrong way' in the hope that, when we work it out, the whole shebang can be reversed to suit.If not, I will have to 'simulate' the engine torque with wash effects, which will require that 'engine torque be turned off whilst flying (or you'll have the rock 'n' roll we've got now).Next week I'll post you all a physics file to try, if not 2!Have a great weekend :-beerchugJon Point*************************(effyouthree@hotmail.com)*************************

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Jim,"Jon: Maybe just a tad louder ? He, he, he."(Voice from Star Trek) "She's already clipping, Captain - the engine's just ain't goin' to take it..." Seriously, I can't really make it any louder without clipping it even more (then it just sounds like a chainsaw through a cheap speaker - like some of the standard LGS sounds). As it is, you have to turn down the engine sound to hear the radio - although, with the abuse we're likely to get from ATC with this thing, that may be good ;)"Just love that ticking at idle, and the prop thrashing at the top end."Thanks. BTW, the idle sound is about 50/50 Beaver and GeeBee - I needed the Beaver sounds for the low-end. The GeeBee idle sound was very thin but the exhaust noise... sweet-as :-) The top end is actually DC3 with a bit of Beaver prop noise over the top! Everything was done as external sounds then filtered and bass-boosted to rattle your head in the cockpit! I just had a problem editing around the fuselage vibes in the Beaver sounds but I think it'll do as is now :-hah Have a great weekend :-beerchugJon Point*************************(effyouthree@hotmail.com)*************************

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