Design: Dihedral Recommendation

[jim ivey]

Ted
Most of those style planes are flat across the top of the wing. I built my extra with wing on table upside down and flat. This gives a effective dihedral due to the thinner tips. I don't believe you would go wrong here to do it that way.

Jim Ivey


----- Original Message -----
From: george kennie
Sent: Saturday, May 10, 2003 10:34 PM
To: discussion at nsrca.org
Subject: Re: Design: Dihedral Recommendation

Put in 7/32" dihedral, and move the stab down an additional 1/2". Of course we
don't know what the engine offsets are( I think I would try 2&1/2 right and
1&1/2 down).
Does that thing have a balanced rudder? If it does, you'll have adverse couple
with what the manual calls for.
Good luck.
G.

Ted Sander wrote:

> It's flying season, and for all sorts of poor reasons, I'm just now getting
> to boring holes for my wing tubes in my scratch built Edge 540.  While not
> pure pattern, I hope to get it to come in "pattern legal", so I can use it
> as a dual purpose intermediate plane for our few local pattern and IMAC
> contests.  Wing is 1 3/4 " below thrust line, stab 1" below.  Standard
> straight leading edge (what makes it an "Edge").  Original plan was no
> dihedral at all (centerline of tips on same plane as the root).  Now I'm
> starting to question myself.  Realizing that there are lots of things that
> contribute to roll coupling I haven't included here, anybody have rough
> guidelines on a starting place for the dihedral angle to build in, if any?
> Plane will have most of the provisions for getting it dialed in - wing/stab
> adjusters, even a way for moving stab up or down, if needed.  Dihedral will
> have to be built in.  If the rest of the plane proves itself out, I have no
> issue fine tuning the design in the future by cutting new wings - but would
> like to at least get it sort of close for this first attack.  How much
> dihedral does a Focus have, for example?  Any words of wisdom if I should
> increase or decrease it due to the effective forward taper of the wing?
> Thanks in advance for any advice.
>
> =====================================
> # To be removed from this list, send a message to
> # discussion-request at nsrca.org
> # and put leave discussion on the first line of the body.
> #

Ted Sander wrote:

> It's flying season, and for all sorts of poor reasons, I'm just now getting
> to boring holes for my wing tubes in my scratch built Edge 540.  While not
> pure pattern, I hope to get it to come in "pattern legal", so I can use it
> as a dual purpose intermediate plane for our few local pattern and IMAC
> contests.  Wing is 1 3/4 " below thrust line, stab 1" below.  Standard
> straight leading edge (what makes it an "Edge").  Original plan was no
> dihedral at all (centerline of tips on same plane as the root).  Now I'm
> starting to question myself.  Realizing that there are lots of things that
> contribute to roll coupling I haven't included here, anybody have rough
> guidelines on a starting place for the dihedral angle to build in, if any?
> Plane will have most of the provisions for getting it dialed in - wing/stab
> adjusters, even a way for moving stab up or down, if needed.  Dihedral will
> have to be built in.  If the rest of the plane proves itself out, I have no
> issue fine tuning the design in the future by cutting new wings - but would
> like to at least get it sort of close for this first attack.  How much
> dihedral does a Focus have, for example?  Any words of wisdom if I should
> increase or decrease it due to the effective forward taper of the wing?
> Thanks in advance for any advice.
>
> =====================================
> # To be removed from this list, send a message to
> # discussion-request at nsrca.org
> # and put leave discussion on the first line of the body.
> #

=====================================
# To be removed from this list, send a message to  
# discussion-request at nsrca.org
# and put leave discussion on the first line of the body.
#
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.f3a.us/pipermail/nsrca-discussion/attachments/20030510/c268904c/attachment.html