tenacious101010

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I have an American Eagle BT-13 Composite fuselage and need help as to how to attach the horiz and vert stabs. I thought of building them to flush mount to the stubs on the fuselage with a spar running thru the fuse and holes cut for the spar. This seemed like it would be tough to keep everything aligned properly like building the stab on a building board would. Another option seems to be to completely cut out the ends of the horiz stab stubs and sliding a pre built horiz stab assy thru the opening but that didnt seem like it would be easy to get the opening accurate to fit the stab.
Does anyone have any pictures and/or suggestions? I assume the vertical stab will go in similar to the horizontal method, using a vertical spar to interlock into the horizontal stab. Any help would be greatly appreciated. Pictures would be a great help.
Thanks, Denny

Ed Smith

How you do this will determine how the airplane flies, so pay attention to the step by step.

Finish the stab complete. Gouge out the fuselage stubs so the stab slides through EASILY, not tight.

The stab has to be aligned to the wing in four dimensions, horizontally, side to side, square (LE to LE) and incidence. So you will need the finished wing screwed to the fuselage in it's final position.

See the pictures. You will need at least two incidence meters. I am using three. Forget moving one meter around. Set up the fuse/wing assembly with the correct incidence. Slide the stab in place and set to the four aforementioned dimensions. When it is correct glue it in place with the appropriate glue/resin/filler.

The vert stab has to be correct to two dimensions, vertical squareness and centre line offsite. With the experince with the stab installation I am sure you can figure that out.

Of course you could ignore all of the above. Just slap it all together and wonder why the airplane flies like a brick outhouse. If it ever gets off the ground.

Ed S

tenacious101010

My Feedback: (97)

Thanks for the in depth explaination Ed. I just needed ideas from someone with experience with the composite fuselage and attachment of the stabs. Normally I would be telling someone that didnt understand the alignment proces the same thing, but I will probably build the stabs, install them, then align my wing to the fuselage and the horizontal. I am building this project with an American Eagle composite fuselage but using a wing made from Brian Taylor plans. I did not recieve the foam wing cores, so I dont have a reference as to where front of the leading edge should be as far as incidence. I am adapting a wing profile (airfoil) that was not designed for this composite fuselage and the wing saddles are not even close, they will need reshaping so it may be easier to align the wing to the horizontal. The alignment of the horizontal is pretty close to where it needs to be so if I build the horizontal and align it with the fuselage horiz stab stubs, I can then mount the wing aligned with that and then rework my wing saddles. Thanks again for the input on attaching the stabs.
Denny

moggyman64

Hi Ed Smith,

Great reply to this post, can I ask you what you mean by "centre line offset" relating to the rudder. I thought that the centre line of the rudder would fit to the centre line of the fuse.

Regards

keith