|
|
|
| Electric Flight Discuss Electric Flight in Canada |
Topic Review (Newest First)
|
| 11-25-2010 10:00 AM | ||
| Max |
Re: Biplane---which wing used to check CG??? Quote:
|
|
| 11-24-2010 09:41 AM | ||
| JimMcIntyre |
Re: Biplane---which wing used to check CG??? Quote:
Best answer is, find the CG for both wings (taking sweep into account) separately and average this point (choose the point halfway between). To take sweep into account: if constant chord wing, average 30% mac from midpoint and tip. If tapered wing, use weighted average based on area. The exception (always one) is when one wing has significantly less area than the other, then adjust accordingly (e.g. if one wing has 50% less area than the other, move 50% further toward the larger wing's CG). Not an exact science but close enough. Err on the safe side, balancing nose heavy for the first flight. Best of luck! |
|
| 11-23-2010 02:22 PM | ||
| Max |
Re: Biplane---which wing used to check CG??? Quote:
Many Bippers have the top wing straight and the lower wing swept. In that case you have to calculate the mean aerodynamic chord (MAC) for both wings and then find the 1/2 way point between the 2 MAC's [disclaimer- there is more to it than that, but that should work for most cases] As DO335 mentions, the CG is relative to the fuselage, so once you know where it should be, it doesn’t matter whether you pivot it from the top wing or bottom wing (as long as the pivot is over the CG point you calculated) |
|
| 11-20-2010 12:54 AM | ||
| benchfitter |
Re: Biplane---which wing used to check CG??? just co down from the leading edge of the forward wing and down from the trailing edge of the rearward wing and take 30percent of the two together and thats your cg . |
|
| 04-15-2009 08:15 PM | ||
| Terry Gauvin |
Re: Biplane---which wing used to check CG??? Quote:
1) Top wing directly above the bottom wing: no stagger 2) Top wing more forward than bottom wing: + stagger 3) Top wing further behind bottom wing: - stagger |
|
| 04-15-2009 06:20 PM | ||
| stilly |
Re: Biplane---which wing used to check CG??? You lost me -----negative stagger-----don't know what you mean. |
|
| 04-15-2009 08:16 AM | ||
| DO335 |
Re: Biplane---which wing used to check CG??? Quote:
If your wings have negative stagger, you' d probably find it easier to suspend the plane inverted from the lower wing and balance that way. So much for always hanging off the top wing. Just be certain that the CG is at the specified location. |
|
| 04-14-2009 10:32 PM | ||
| stilly |
Re: Biplane---which wing used to check CG??? on top of the top wing(model upside down)or on the bottom of the top wing |
|
| 04-14-2009 09:28 PM | ||
| Bdegan |
Re: Biplane---which wing used to check CG??? Biplanes are generally balanced using the top wing. At least all three of mine have beem that way. Never pay again for live sex! | Hot girls doing naughty stuff for free! | Chat for free! |
|
| 04-14-2009 09:00 PM | ||
| stilly |
Biplane---which wing used to check CG??? l have a World Models biplane ep.Which wing do you check the CG of the plane on??The upper wing or the bottom wing.lt says in the manual --3.25 back from the leading edge of the wing where it meets the fuse.But the picture that they show you is measured on the upper wing.Any ideas. |
|
Your Privacy Choices