I felt you needed a bit of support ;-)
N
On 31/07/2013 14:22, GRAHAM SINGLETON wrote:
> Thanks for that Nigel
> As you say, fascinating! I'm glad my memory is not so innacuarate
> after all!
> Graham
>
> ------------------------------------------------------------------------
> *From:* "nigel_graham@m-tecque.co.uk" <nigel_graham@m-tecque.co.uk>
> *To:* europa-list@matronics.com
> *Sent:* Wednesday, 31 July 2013, 13:42
> *Subject:* Re: Europa-List: Tri-gear Flap Cross Tube Slot Length
>
> A fascinating insight into the reasoning behind the recommendation for
> the optimum flap setting can be found on page three of this early
> factory newsletter, dated March 1994.
> This did of course relate to the first prototype, G-YURO, which was
> powered by the 80 horse 912 driving a fixed pitch Warp Drive prop.
>
> Happy days. The enthusiasm and excitement was palpable. Isn't it time
> somebody developed a new homebuild?
>
> Nigel
>
>
> On 30/07/2013 10:23, Frans Veldman wrote:
> <frans@privatepilots.nl <mailto:frans@privatepilots.nl>>
> >
> > On 07/29/2013 11:25 AM, GRAHAM SINGLETON wrote:
> >
> >> don't use 30 degree flap, Europa tested it and found you are
> starting to
> >> lose aileron control at the low speeds achieved in ground effect.
> > I have some trouble believing this (and even when it is true it is
> > questionable whether this is still a valid reason for the XS with the
> > increased aileron span and with more powerfull engines).
> >
> > With higher flap settings you are getting more drag than additional
> > lift. With 10% more flap (30 degree instead of 27) you will get maybe
> > just 5% more lift. If the ailerons are inadequate for this tiny bit of
> > extra lift I think they would have difficulties handling 27 degrees as
> > well. Furthermore, in the XS the ailerons are substantially increased in
> > lenght, significantly more than 5%, and should have much more control
> > power at low speeds! Even if control problems were the limiting factor,
> > than it is questionable whether the same limit would still be needed for
> > the XS.
> >
> > I thought that the limitation in flap was because of the 80hp engine
> > used for the certification, which might have lacked sufficient power to
> > exercise a go around with full flaps under full load (which is, if I
> > remember correctly, a certification requirement. For the same reason the
> > older Cessna's have 40 degree flaps, where the newer ones have 30 degree
> > which was instantly rewarded with a 30Kg higher MTOW without any
> > structural changes).
> >
> > Furthermore, in the tri gear the fact that you have the option to use 30
> > degree flaps doesn't mean that you will have to use this all the time.
> > There are situations where more flap would be welcome, and there might
> > be situations where using less flap would be better. I can't see the
> > benefit of the 26 degree limit. Of course for the mono you have no other
> > option than to land with full flaps, so maybe in this case the
> > limitation is justified.
> >
> > I know folks having drilled a new hole in the lugs on the flap control
> > tube, so that the actuator can drive the flap further (and faster). No
> > control difficulties are observed even in quite a few nasty situations
> > with 30 knots wind and lots of turbulence. Instead the short field
> > capabilities are somewhat improved.
> >
> > Regards,
> > Frans
> >
> >
> >
> >
> >
> >
>
>
> *
>
>
> *
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