stunthanger.com

General control line discussion => Open Forum => Topic started by: Kevin Wright on September 11, 2012, 07:42:37 AM

Title: Preferred Imitation Stab Thickness
Post by: Kevin Wright on September 11, 2012, 07:42:37 AM

Folks,
I'm about to do final assembly of my first Fancher Imitation (Fuse, Wing and Stab completed)
and I've just noticed a potential issue with the stab thickness shown on my set of plans.
My plan set was ordered from Steve Moon of UltraHobby and show the stab as being
1/2 inch thick however, elsewhere on this forum the stab is shown as being about 1 inch thick.

Can anyone out there clarify before I glue the stab in place?

Thanks,
Kevin

Title: Re: Preferred Imitation Stab Thickness
Post by: Bill Little on September 11, 2012, 10:49:32 AM

HI Kevin,

The original Imitation used a fully airfoiled stab/elev. about 1" thick.  Maybe Ted and Brett will have an opinion and will chime in here.

BIG Bear
RNMM/AMM

Title: Re: Preferred Imitation Stab Thickness
Post by: Mike Griffin on September 11, 2012, 03:59:09 PM

Kevin here is a previous thread I started on this subject you might want to look at.

http://stunthanger.com/smf/index.php?topic=28374.0


Mike Griffin

Title: Re: Preferred Imitation Stab Thickness
Post by: Brett Buck on September 11, 2012, 10:33:02 PM

Quote from: Kevin Wright on September 11, 2012, 07:42:37 AM

Folks,
I'm about to do final assembly of my first Fancher Imitation (Fuse, Wing and Stab completed)
and I've just noticed a potential issue with the stab thickness shown on my set of plans.
My plan set was ordered from Steve Moon of UltraHobby and show the stab as being
1/2 inch thick however, elsewhere on this forum the stab is shown as being about 1 inch thick.

Can anyone out there clarify before I glue the stab in place?

Thanks,
Kevin

  The original has/had a 1" thick deeply airfoiled stab and that is what is shown on the plans. I don't know what the Ultrahobby plans show, but I expect it is 1/2" thick and flat with a round LE.  Either would probably work fine, but since you have it built I would suggest going ahead and using it. My Imitation XL has that sort of stab and it qualified at many NATs with no real problems.

     I will allow Ted to speak for himself of course, but in general I am not a big fan of the 1/2" thick flat stab. Many times it works well, and occasionally we have run into problems. These are minor problems, generally "princess and the pea" sort of problems. It usually manifests itself and slight difficulties with getting the bottom of square maneuvers perfectly flat. All of the local flat stabs have ended up with turbulators applied near and on the LE, which more or less fixed it. But a whole lot of airplane have been with that sort of stab, since it was what Paul Walker used on the Impact, and most of them flew fine.  

    I think the ideal stab shape is about 1/2" thick with an "arc" airfoil and about a 1/16" LE radius. AND the corners rounded off at the elevator hinge line.

   Brett

Title: Re: Preferred Imitation Stab Thickness
Post by: Tim Wescott on September 11, 2012, 11:10:35 PM

Quote from: Brett Buck on September 11, 2012, 10:33:02 PM

    I think the ideal stab shape is about 12" thick with an "arc" airfoil and about a 1/16" LE radius. AND the corners rounded off at the elevator hinge line.

One foot?  Or is there supposed to be a decimal point in there?

Title: Re: Preferred Imitation Stab Thickness
Post by: Brett Buck on September 11, 2012, 11:11:44 PM

Quote from: Tim Wescott on September 11, 2012, 11:10:35 PM

One foot?  Or is there supposed to be a decimal point in there?

  How about a slash?

    Brett

Title: Re: Preferred Imitation Stab Thickness
Post by: Walter Hicks on September 16, 2012, 09:21:23 PM

Here is one that is currently flying - Even has Ted F signature on it. One of the better ones . PA 61 Se  60 oz.  Note stab thickness!

(http://i45.tinypic.com/25qvwyd.jpg)



(http://i46.tinypic.com/21ou3aq.jpg)


(http://i45.tinypic.com/29f7zme.jpg)