Bud, thanks for your reply. Pete has already jumped in and asked my next
question. Thanks again, Paul
On Mon, Jan 18, 2021 at 8:22 AM Bud Yerly <budyerly@msn.com> wrote:
> From history Paul.
>
>
> Raise the popular tail wheel aircraft and note the position in level
> attitude of the main axle to the leading edge of the mean aerodynamic chord.
>
> If you drop a plumb bob from the leading edge of a say a 7AC Champ or
> Citabria (rectangular wing so the mac is the leading edge) the string goes
> through the axle.
>
>
> There are many aerodynamic effects as well as geometry effects to
> positioning landing gear for a delightful conventional setup.
>
> As you push the stick forward, the main wing begins to go negative
> preventing nose over as the tail cannot overpower the wings negative lift.
>
> The gear length allows a very near stall attitude at touchdown.
>
> The elevator position is such that it is above the wing downwash at
> touchdown for stalled landings.
>
> Rudder area is such that the rudder can control the aircraft below stall
> speed.
>
> Fuselage area vs tail area and sideslip capability for crosswinds.
>
>
> Geometry is important also. Much has been written:
>
> The angle of the gear to the CG to the vertical CG axis longitudinally.
>
> The angle of the gear to the CG laterally for stability.
>
> Tail volume and length in relation to the gear. (AKA short coupled)
>
> Tail wheel to main gear distance in relation to gear width.
>
> Main gear movement in relation to touchdown forces (splay, compression,
> springiness etc.).
>
>
> All these things determine whether a conventional gear aircraft is
> delightful or a handful to land.
>
>
> Best Regards,
>
> Bud Yerly
>
>
> *From:* owner-europa-list-server@matronics.com <
> owner-europa-list-server@matronics.com> *On Behalf Of *Paul McAllister
> *Sent:* Sunday, January 17, 2021 10:16 PM
> *To:* europa-list@matronics.com
> *Subject:* Europa-List: Aerodynamicist question - Bud Yerly
>
>
> Hi Bud (and anyone else who is knowledgeable on the topic)
>
>
> I was once told l that there is an ideal front wheel position for tail
> drggers, something like 100mm in front of the MAC and that wheel placement
> of the mono was not ideal. I can't remember where I heard this or if it
> was from a knowledgeable source.
>
>
> Would you happen to know if there is any validity in this?
>
>
> Thanks and regards, Paul
>
|