>>
> The real confusion is that there are people
> flying around with the anti
> servo tab not in line with the tailplane. This
> means they are either
> pulling or pushing slightly on the stick, or
> that the tailplane is not
> balanced out properly.
Frans, take it again:
Balancing is nothing to do with that.
Balancing is to prevent possible flutter.
Only case when the trim tabs and the stabilator
are in line is then, when they are in their
neutral position.
That is if the plane is correctly build as per
manual.
In that case only the plane is in its cleanest
condition.
You are able to achieve that with a certain
combination of weight, speed, CofG etc but that is
a special case.
What faster we fly that more we get lift by wings.
That is why we have to push more or trim nose down
= trim tabs move upp when flying faster.
The stabilators=B4 trailing edges move then down.
They cannot be in-lined any more.
Overall, tailplanes /stabilators are neutralized
only when CofG = CofL (w zero stick forces).
If you have to declect tailplanes (and wanna
neutralize stick forces) you have to trim trim
tabs to other direction.
The aerodynamical forces /deflected trim tab are
then equal with the aerodynamical forces
/deflected tailplanes.
They are balancing then each others by
aerodynamically.
They have to be un-lined normally, more or less!
If not I am a Donald Duck!
That is why we usually and almost always see them
(trimtabs) in deflected position only.
I am sure you will confirm that when you get take
more photos.
In your photo you were flying 110 knots, w/o stick
forces, trim tabs and tailplanes in line:
congratulations, your plane is very economical
with that speed because obviously tailplanes are
in their neutral position and the plane is most
streamlined.
Otherwise - your neutral is not exactly neutral.
I assume your fuelflowcomputer will confirm that.
If you wanna fly slower or faster (with same load
and conditions) I am sure your tailplanes and trim
tabs are not any more in line.
The stick forces in Europa are quite light around
100 knots. Also the necessary movements to keep
level flight are small.
I would like to say: almost invisible when looking
photos!
Look at attached photo: I was flying around 120
knots with one Dynamic WT9.
My trim tabs are slightly deflected upwards - so
the stabilators have to be deflected downwards a
little bit.
If flying faster - they have to be deflected even
more of course.
The stabilators are very powerful - that is why
they are near their neutral position almost
always.
That is why also the trim tabs are *almost*
in-line fith stabilators.
Notice - just almost. If you have trimmed, they
are not exactly in-lined any more.
***
Concorde did this by pumping fuel into fin or out
---From there. The stabilators could be so almost
always in their neutral position and the plane was
very clean.
With Europa, we could have let is say 10 kilos of
fuel inside the fin...
That was my thought only. No confusion at all.
Just aerodynamic.
I am sure I will get a fast speed reply ;)
Raimo
Terveisin, Raimo Toivio
Europa XS Mono OH-XRT #417
37500 Lemp=E4=E4l=E4
FINLAND
p +358-3-3753 777
f +358-3-3753 100
toivio@fly.to
www.rwm.fi
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