Maybe I can add a bit more confusion?=0AIn fact the tail plane pivot is not
at the neutral point, it's slightly forward I think (Mike?) You're right t
hat the tab is anti balance.=0AWith symmetrical sections aerodynamic centre
doesn't move, that's why all flying tails are usually symmetrical. (afaik)
Add the effect of the displaced tab and you have camber so the section wil
l now provide lift at zero AoA. ie tailplane in trail? This lift is just e
nough to balance the wing pitching moment. Increase speed and you get more
lift so nose will pitch up. Speed reduces again etc. =0AGraham=0A=0A=0A=0A
=0A________________________________=0AFrom: Frans Veldman <frans@privatepil
ots.nl>=0ATo: europa-list@matronics.com=0ASent: Monday, 12 April, 2010 19:5
1:09=0ASubject: Re: Europa-List: Effects of Flaps and Ailerons on Pitch Tri
s.nl>=0A=0AOn 04/12/2010 08:06 PM, Peter Zutrauen wrote:=0A=0A=0A=0AThe onl
y thing I'm troubled with is that the stable rest position of the=0Atailpla
ne plus trim tab is not when they are perfectly lined out in=0Arelation to
each other.=0A=0AMaybe, just maybe, this may have something to do with the
fact that the=0Ahinges are on the upper side of the tailplane, rather than
in the=0Acenter. The forces acting on the lower side have more leverage tha
n the=0Aforces acting on the upper side, hence the stable position of the t
rim=0Atab where all forces are cancelled out, is slightly up.=0A=0AThe more
I think about this, the more I think that this is the reason=0Awhy we alwa
ys see a trim tab up position.=0A=0AAny comments about this hypothesis?=0A
=0AFrans=0A
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