Re: Larger fuel tank under seat + higher cabin headroom.


Doug Humble <hawkidoug@...>
 

Please don't take offense Chris - but I think the "flogging" was before you acknowledge you wanted to make significant changes to the Quickie design. This list isn't meant for those kind of discussions. I'm not sure the Performance list is either, but I don't belong. We are basically here to help those building the Q2/Q200 in its current form. The successful builders and fliers here try to steer the new people away from drastic design changes and that is sometimes considered "flogging". The intent is to keep everyone safe and, on a more shellfish level, keep our birds reputation from going down the toilet.

It seems to me that there is a design with three flying surfaces out there, but I can not remember what it is called. I'll keep searching until I find it for you.

Doug "Hawkeye" Humble
A Sign Above www.asignabove.net
Omaha NE
N25974

----- Original Message -----
From: Christopher
To: Q-LIST@...
Sent: Thursday, September 14, 2006 8:36 AM
Subject: [Q-LIST] Re: Larger fuel tank under seat + higher cabin headroom.


Here is what has me all fired about about a stabilizer and elevator
on the Tail:

Quote:

Hi Chris,

Here is quick summary of what I know about adding a T tail to a
tandem Wing airplane:

1. DO NOT add anything other than a sub foot span sized T tail to
your Project unless you are a structural engineer or you have a
structural engineer direct your modification effort by calculating
how much reinforcement the tail cone and vertical fin will need for
a given size H. Stab.

2. The T tail opens up the performance envelope of a tandem wing
plane. They cruise faster by 5-10% and land slower by about the
same margin. The glide slope angle is much more controllable and
approach speed is much more manageable with an elevator on an aft
stabilizer driving the pitch control. As a side benefit, you don't
need elevators on the front wing any more once elevators are
installed on a medium sized H. Stab. so you can add flaps to both
wings. This reduces the stall speed yet further and turns the
planes into STOL capable performers.

3. The elevator on the T tail can work on conjunction with the
canard Elevators if you don't want to modify the standard dragonfly
control system beyond adding an elevator to a T tail stabilizer. I
found in my X plane simulation of a Q200+ 5' span T tail H. Stab.
that reducing the canard elevator throw to about 20%of normal and
using the elevator on the T tail for most of the pitch control made
a much easier flying plane than an unmodified Q200 for the same
reason above: slow flight was much more controllable and speed
management was much better.

It was possible to slow the plane down in a 2g steep turn and have a
steeper glide slope than without the T tail. Stalls are more
predictable and flare can be much deeper without the pitch buck
or "nodding" that canard planes do when at minimum speed. No
smashing nose first into the runway when coming in too slow.

4. The X plane simulation T tail Q200 had snappier handling than
the Unmodified Q200 and was much more fun to fly around. The normal
Q200 feels a lot like a C172 or Boeing 737. the T tail Q200 feels
more like an Extra 300.

5. I gave up my plans to build a Q200 and have since designed my
own T Tail Q200 variant. Once I finish my mechanical engineering
degree I will conduct a series of structural analyses and design the
airframe. The aerodynamic characteristics of the X plane model of
this design will be proven with a 1/3
scale radio controlled model.

------------------

--- In Q-LIST@..., "Darrell Daniels" <log@...> wrote:
>
> Chris,
> I was thinking one goy on the group had a T Tail and took the
tail off.
> Darrell
> ----- Original Message -----
> From: "Christopher" <qdf_files@...>
> To: <Q-LIST@...>
> Sent: Thursday, September 14, 2006 4:29 AM
> Subject: [Q-LIST] Re: Larger fuel tank under seat + higher cabin
headroom.
>
>
> > David,
> >
> > Thanks for responding... I, if I am being told accurate
information
> > is that the performance envelope of the Q are opened up with a T-
> > Tail allowing slower approach speeds if the a stabilizer with an
> > elevator is added to the top of the tail which is five to six
feet
> > long becoming a tri-foil aircraft... if you wan't to call it
that.
> >
> > I wanted to look into deleting the elevators off the canard, if
this
> > can be done. I don't care if the airplane becomes something else
if
> > the performance is improved by as much as 10%.
> >
> > Due to the public floggings of opinion which come about from
someone
> > even suggesting a radical change to these airplanes I want to
keep
> > discussion off list, if you would be willing to do so. I have
been
> > referred to you for some other questions I had too.
> >
> > I have a DF, but the way I see it, except for the length of the
> > wings they are the same airplane, essentially and this mod, if it
> > works as well as claimed by someone who did a study on the T-
Tail,
> > would apply to either aircraft. This group is much more active
than
> > the DFly group so I passed the question here about this
possibility
> > plus I wanted to look into the idea of flapperons, but not my
main
> > thrust of interest, mainly the T Tail and perhaps a raised
canopy so
> > I don't hit my head on the top.
> >
> > Christopher
> >
> > -- In Q-LIST@..., "David J. Gall" <David@> wrote:
> >>
> >> What was the project?
> >>
> >>
> >> David J. Gall
> >>
> >> > -----Original Message-----
> >> > From: Q-LIST@... [mailto:Q-LIST@...]
> >> > On Behalf Of Christopher
> >> > Sent: Wednesday, September 13, 2006 5:44 PM
> >> > To: Q-LIST@...
> >> > Subject: [Q-LIST] Re: Larger fuel tank under seat + higher
> >> > cabin headroom.
> >> >
> >> > That's the same thing an engineer told me on another project
> >> > which suceeded.
> >> >
> >> > Christopher
> >> >
> >> > Tht--- In Q-LIST@..., oneskydog@ wrote:
> >> > >
> >> > >
> >> > > In a message dated 9/13/2006 8:12:52 AM Mountain Daylight
> > Time,
> >> > > qdf_files@ writes:
> >> > >
> >> > > I'm pretty dedicated
> >> > > towards doing something different from a regular Q or DF
with
> > my
> >> > > project even if it takes me ten years to finish it. I want
to
> > put
> >> > a
> >> > > T-Tail on it as the sole elevator and perhaps look into
> >> > flapperons
> >> > > for both wings.
> >> > >
> >> > >
> >> > >
> >> > > >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>.
> >> > >
> >> > > DOA RIP
> >> > >
> >> > > Regards,
> >> > >
> >> > > One Sky Dog
> >>
> >
> >
> >
> >
> >
> >
> > Quickie Builders Association WEB site
> > http://www.quickiebuilders.org
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
>

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