Tailplane question

[Lou Parker]

I'm building the tail-plane of my wooden aircraft and the plans have
specific measurements of the ribs every couple of inches to get the
shape from leading edge back. Unfortunately when I built the ribs it
came out looking as if it would create a whole lot of drag. In fact
when I follow the measurements, the first 3 inches go from 1/2" to 3"
in thickness immediately, and then smooth out. Not only does this just
look wrong, but not even close to the drawing supplied. I've checked
my numbers 3 times now, and keep getting the same results. Can anyone
tell me where to find information on the design and construction of
tail-planes? I may have to redesign this part.
Lou

[Ed Wischmeyer]

> I'm building the tail-plane of my wooden aircraft and the plans have
> specific measurements of the ribs every couple of inches to get the
> shape from leading edge back. Unfortunately when I built the ribs it
> came out looking as if it would create a whole lot of drag. In fact
> when I follow the measurements, the first 3 inches go from 1/2" to 3"
> in thickness immediately, and then smooth out. Not only does this just
> look wrong, but not even close to the drawing supplied. I've checked
> my numbers 3 times now, and keep getting the same results. Can anyone
> tell me where to find information on the design and construction of
> tail-planes? I may have to redesign this part.

Tailplane drag is not likely to be all that significant in the grander
scheme of things. A thicker tailplane can give you more authority. The
TurbineLegend and its descendants had tailplane thickness of either 13
or 16% (forget which), and I believe the RV series is at 9%. This isn't
an engineering answer, of course, but it doesn't sound to me like you've
necessarily got a problem.

What kind of plane is it, and what speed range? What are the chord,
thickness, and span of the tailplane?

Ed Wischmeyer

[Jan Carlsson]

check the coordinats one more time, so you don't have a comma in the wrong
place!?

Jan Carlsson

"Lou Parker" > skrev i meddelandet
om...
> I'm building the tail-plane of my wooden aircraft and the plans have
> specific measurements of the ribs every couple of inches to get the
> shape from leading edge back. Unfortunately when I built the ribs it
> came out looking as if it would create a whole lot of drag. In fact
> when I follow the measurements, the first 3 inches go from 1/2" to 3"
> in thickness immediately, and then smooth out. Not only does this just
> look wrong, but not even close to the drawing supplied. I've checked
> my numbers 3 times now, and keep getting the same results. Can anyone
> tell me where to find information on the design and construction of
> tail-planes? I may have to redesign this part.
> Lou

[Ed Sullivan]

"Jan Carlsson" > wrote in message >...
> check the coordinats one more time, so you don't have a comma in the wrong
> place!?
>
> Jan Carlsson
>
> "Lou Parker" > skrev i meddelandet
> om...
> > I'm building the tail-plane of my wooden aircraft and the plans have
> > specific measurements of the ribs every couple of inches to get the
> > shape from leading edge back. Unfortunately when I built the ribs it
> > came out looking as if it would create a whole lot of drag. In fact
> > when I follow the measurements, the first 3 inches go from 1/2" to 3"
> > in thickness immediately, and then smooth out. Not only does this just
> > look wrong, but not even close to the drawing supplied. I've checked
> > my numbers 3 times now, and keep getting the same results. Can anyone
> > tell me where to find information on the design and construction of
> > tail-planes? I may have to redesign this part.
> > Lou

You didn't mention the name of the aircraft you are building, and have
you checked with the designer?

Ed Sullivan

[Badwater Bill]

>
>You didn't mention the name of the aircraft you are building, and have
>you checked with the designer?
>
>Ed Sullivan


Ed:

I thought you were dead.

BWB

[Badwater Bill]

On 19 Jan 2004 07:43:37 -0800, (Lou Parker) wrote:

>I'm building the tail-plane of my wooden aircraft and the plans have
>specific measurements of the ribs every couple of inches to get the
>shape from leading edge back. Unfortunately when I built the ribs it
>came out looking as if it would create a whole lot of drag. In fact
>when I follow the measurements, the first 3 inches go from 1/2" to 3"
>in thickness immediately, and then smooth out. Not only does this just
>look wrong, but not even close to the drawing supplied. I've checked
>my numbers 3 times now, and keep getting the same results. Can anyone
>tell me where to find information on the design and construction of
>tail-planes? I may have to redesign this part.
> Lou


Do not redesign anything. You didn't mention what airplane you were
building but 3 inches is nothing since the tailplane is streamlined
when you get the skin on it. The airplane most likely needs that meat
for strength.

BWB

[Ed Sullivan]

(Badwater Bill) wrote in message >...
> >
> >You didn't mention the name of the aircraft you are building, and have
> >you checked with the designer?
> >
> >Ed Sullivan
>
>
> Ed:
>
> I thought you were dead.
>
> BWB

Bill,

Only in the dorsal lower mid region

EBS