Aileron Cove Gap

[Acroeric]

Does anyone have an idea what the actual cove to aileron gap is supposed to be? on a BC series airplane? I can not find it in any of my manuals or drawings.

[3Dreaming]

I've never seen or heard a number quoted, it is what it is.

[Acroeric]

Not really in this case- I'm making new coves and can set it to whatever is right.

[Ragwing nut]

https://digital.library.unt.edu/ark:/67531/metadc61626/m1/15/

[3Dreaming]

Not really in this case- I'm making new coves and can set it to whatever is right.

My point was there is no published number, because the parts are designed to set the proper gap. With trying to adjust it can you make it better, maybe. Can you make it worse, absolutely.

[PA1195]

Eric.....some offshore porn entity has grabbed your www/bullyaero.com. Note the pre and post WWII coves are different. Pre has a sharp lower entry edge like Piper's J- and PA-series; post (F-19 for example) has a rounded edge. Not sure of the gap once the aileron is deflected.

Gary

[astjp2]

If the ailerons are rubbing, you have a problem, if there is any gap, it’s probably ok. What is important is the leading edge of the ailerons tipping down into the slipstream when the ailerons moves to counter the adverse yaw. IMHO Tim

[Robert Lees]

As others have said, the gap is not specified. But is important to have a gap, to ensure airflow attachment over the top surface of the aileron at full aileron-down deflection.

We had an F22 here at my airfield (before it got totalled), and it had faired aluminium gap seals on the upper surface from the factory. They were attached to the upper wing surface with screws, and essentially prevented air from flowing between the wing cove and the aileron leading edge.
The roll rate was abysmal as a result. I wonder if John Polychron et al thought it was for streamlining or for looks?

I have no photos, sorry.

Rob

[Acroeric]

Sorry guys- I probably should have been more specific..... I have built new wings for my Clipwing and also new composite coves. The airplane is experimental. These are now all wood wings and I have been able to make them much more precise than what they are replacing. I will not have any fabric pulling loose etc. I'm familiar that there needs to be a gap and the science behind the aileron design- I was just hopeful there was some gap range out there somewhere for an optimum start. I have some stock ribs and coves so can just build a mock up and measure those for a start. Much of this stuff has been rebuilt so many times it is hard to tell which were the original placement of screws.

I saw our old website had been recycled- my new business took me away from working on others airplanes a few years ago and we let the web page go then as well. I'm almost afraid to check!

Mike- thank you very much for the link to the old NACA report. I have been reading those but had not seen that one!

[Ragwing nut]

When we bought a clipwing project years ago from Bill Zivko, he had made aileron hinges using rod ends so he could adjust placement. Didn't know if that was your plan or went a different route.

[Acroeric]

I am just using stock dimensioned hinges. I have made them of square stock instead of C channel. I need pics of the Zivko clipwing!! Know those guys well. They do nice work.

[PA1195]

From the above NACA report: 63" wing chord x 0.005wc = 0.3125 ~ 5/16" drill size.

Gary

[Ragwing nut]

I am just using stock dimensioned hinges. I have made them of square stock instead of C channel. I need pics of the Zivko clipwing!! Know those guys well. They do nice work.

they didn't get very far and never finished it which is why we ended up with it. We got the most perfect '47 fuselage we ever owned with the project. I still have a box of all the custom pieces and forming blocks they started making, which was mostly aileron stuff.