Yes, but trimming nose down is done to lower the angle of attack of the w
ing, and
thus lower the induced drag, allowing a higher airspeed. It is still pushi
ng down, just not
as much as at lower speeds.
All non symmetrical airfoils that do not have reflex in the trailing edge
have a negative CM (pitching moment). This is why the tail is necessary i
n the first place. The tailplane provides a downforce that balances the ne
gative pitching moment of the wing. In a flying wing design, there is a ne
cessity for more washout at the tips and/or reflex in the trailing edge of
the wing to counteract the negative CM of the wing (effectively adding down
force at the tail).
Without the tail, the wing will rotate nose down and then tuck under.
Glenn
From: mikenjulie.parkin@btinternet.comTo: europa-list@matronics.comSubject:
Re: Europa-List: Europa Tailplane - Mod 73Date: Sun, 15 Jul 2007 01:43:10
+0100
Glenn,
I am not so sure about that statement. As one accellerates, more nose down
trim is required - standard in any aeroplane. That implies that if the ta
ilplane was taken out of the equation, the aircraft would pitch up - not do
wn. Aerodynamicists, am I missing something here??
regards,
Mike
----- Original Message -----
From: glenn crowder
Sent: Sunday, July 15, 2007 12:57 AM
Subject: RE: Europa-List: Europa Tailplane - Mod 73
Once the tailplane(s) departed, the wing by itself has a negative pitchin
g moment. Once themain wing heads down with nothing to stop it, would norm
ally tend to pitch all the way under, which would certainly break the wing
attachments. Glenn
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