Trimming Help

[David Lockhart]

Paul,

Most of the trim advice being given is based (rightly so) on some
assumptions -
- the plane is straight and true,
- ail hinges are sealed,
- servos are tracking evenly throughout the range of throw (as measured by a
throw meter - Budd Laser, CRC, Ivans Gadget, etc),
- all references to ail throw and ail differential refer to actual measured
throw at the aileron (as opposed to an ATV/endpoint/differential setting in
the radio).

Another thing I would suggest - if possible, have another experienced
pattern pilot fly the plane and see if they find the same problem - and it
gives you an opportunity to very critcically watch the plane and evaluate
without needing to concentrate on the actual flying.

As Dean P said, negative ail differential is rarely needed, but not out of
the question.  Most of my planes end up with no differential, or a very
slight amount of positive differential - but I did have one that required
negative differential.

Good luck,

Dave Lockhart
DaveL322 at comcast.net



----- Original Message -----
From: "Paul Lawrence" <pwl45 at yahoo.com>
To: <discussion at nsrca.org>
Sent: Monday, March 29, 2004 8:19 AM
Subject: RE: Trimming Help


> The plane is a Tai Ji 60. I may have found an
> incidence
> problem too. I don't really know where the reference
> line is for this model and I am also still learning
> how to check incidence, but if I block up the plane
> and get the wings at 0 degrees and then check the
> stab, it is showing -1 degree of incidence. That seems
> excessive.
>
> I'm flying Intermediate and the yaw really shows up on
> the humpty bump and full roll up on stall turn. When I
> perform the humpty bump, I pull to vertical, 1/2 roll
> right and the plane heads off to the left(belly in).
> On the full roll up, the plane heads off to the right
> after rolling right.
>
> So far, I have received a lot of good advice and have
> several things to try. Thanks.
>
>
>
> >
> > -----Original Message-----
> > From: Paul Lawrence [mailto:pwl45 at yahoo.com]
> > Sent: Sun 3/28/2004 10:33 PM
> > To: discussion at nsrca.org
> > Cc:
> > Subject: Trimming Help
> >
> >
> > After getting soundly beat in Ocala last weekend, I
> > realized that I have been getting proverse yaw as my
> > plane rolls.
> > It wasn't evident until I saw other well-trimmed
> > planes flying.
> > The plane yaws in the direction of roll input and I
> > have been experimenting with a multitude of aileron
> > differential settings and can't seem to remove the
> > yaw.
> > With zero differential, the plane still yaws in the
> > direction of roll.
> > The trimming chart says to reduce differential in
> > this condition, but I have reduced it to zero.
> > Should I program in negative differential(doesn't
> > sound good) or should I program a litle bit of
> > opposite rudder correction to offset the proverse
> > yaw?
> >
> > Also, does CG and Incidence affect adverse or
> > proverse yaw while rolling?
> > The plane was a little nose heavy and I have also
> > been adding tail weight to try and clean up the
> > rolls, but still can't get that yaw out of the
> > rolls.
> >
> >
> >
>
> =====================================
> # To be removed from this list, go to http://www.nsrca.org/discussionA.htm
> and follow the instructions.
>

=====================================
# To be removed from this list, go to http://www.nsrca.org/discussionA.htm
and follow the instructions.