 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
| HomeDiscussion Groups General ModelsRailroadsRocketsRadio Controlled Air ModelsHelicoptersLand ModelsWater ModelsModelGeeks.com Contact UsLink To UsSearch & Site Map |
Model Forum / Radio Controlled / Air Models / May 2004Goldberg Tiger 2 ?? !!!
I have a newly completed Tiger 2 that was test flown this weekend. The plane performs well except for a tendency to snap to the left when giving large up elevator inputs at moderate to high RPM's. It simply will not do a loop without snapping to the left. I'm not talking a minor tracking problem I mean a full wingover snap. At lower RPM's it behaves as would be expected. The plane is balanced correctly on both axises and is built straight. All incidences are correct. Is this a torque problem? Would a bit of right thrust help? Any help or suggestions would be apreciated. FDW > except for a tendency to snap to the left when giving large up >elevator inputs at moderate to high RPM's. I assume by "high RPMs" you mean high airspeed. How much elevator travel do you have? What do you consider a "normal" loop? A little 1 - 2 degrees right thrust MIGHT help. However, some planes simply won't loop tightly, like in "bite your own tail". I suspect you're trying to loop to tightly with too much elevator travel. This is causing a high-speed stall, and the plane snaps out. Ease off the elevator travel until the plane will loop with full stick input at full throttle and not snap out. Dr.1 Driver "There's a Hun in the sun!" be aware that you can stall the wing at any airspeed!!! I agree with Gerald. I've had the same thing happen to several of my planes. To much elevator at any speed will snap a plane. Keep reducing the travel until at full stick it won't snap. Then you will have as tight a loop as you can get from your plane. Eddie Fulmer You are correct in that I meant airspeed not RPM. But it is not an overcontrol problem. The plane snaps over whenever it gets above 60 degrees A of A or so even with moderate up elevator input. I can't even get vertical without it snapping. I'm going to try a couple of degrees of right and maybe one degree or so of down thrust just for curiosity's sake. I've been flying R/C for nearly 20 yrs. and have never had a plane act this way for no apparent reason. I need to get this thing straightened out since it is my 12yo's first low wing and was picked because it was supposed to be gentle and predictable. I let you know after this coming weekend if the thrust change helped. FDW Let us all know what you find out. Very interesting. Eddie Fulmer >I need to get this thing straightened out One of the other things you may want to check is the wing and tail feathers for warp. You could be introducing more lift one one side than the other. I fly a Tiger 60 and while bigger, is supposed to have similiar flight characteristics. It is one of my favorite take it and fly it planes, like a Chevy, always performs reliably and can always do more than I know how to ask of it. Let us all know what you come up with. Did you make any mods to the kit as you built it? Andy We can make a box of wood.....FLY!! Tail heavy > You are correct in that I meant airspeed not RPM. But it is not an > overcontrol problem. The plane snaps over whenever it gets above 60 degrees [quoted text clipped - 7 lines] > change helped. > FDW Tail heavy? I say NOSE heavy! A forward CG will encourage a snap roll. A nose-heavy airplane flies with excessive up-trim (i.e., decalage) and a resulting higher angle of attack, in order to compensate for the nose-down tendency of the forward CG. As a result, since a nose-heavy airplane flies with too much decalage in normal flight (i.e., up-trim), adding some more 'up' elevator to do a loop will effectively increase the angle of attack to the stalling angle. This results in a pronounced snap roll. BUT, the original poster said the Tiger 2 balances correctly, so I remain mystified. A stumper, indeed. Don Bailey > Tail heavy > [quoted text clipped - 13 lines] > > change helped. > > FDW Has the washout been checked? -- Paul McIntosh http://www.rc-bearings.com > Tail heavy? I say NOSE heavy! A forward CG will encourage a snap roll. > A nose-heavy airplane flies with excessive up-trim (i.e., decalage) and [quoted text clipped - 27 lines] > > > change helped. > > > FDW your problem might be too much elevator. > I have a newly completed Tiger 2 that was test flown this weekend. The plane > performs well except for a tendency to snap to the left when giving large up [quoted text clipped - 5 lines] > thrust help? Any help or suggestions would be apreciated. > FDW Sounds right to me. -- Paul McIntosh http://www.rc-bearings.com > your problem might be too much elevator. > > I have a newly completed Tiger 2 that was test flown this weekend. The [quoted text clipped - 8 lines] > > thrust help? Any help or suggestions would be apreciated. > > FDW |
Reply to this Message |
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2009 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.