All true. Only the structure of the tailplane and its support is
symmetrical in a vertical plane. So if it will take 12 degrees or so in the
"up" direction then it should take similarly in the "down" direction.
Duncan McFadyean
On Friday, February 01, 2002 6:14 PM, Dave Simpson
[SMTP:dave_simpson@londonweb.net] wrote:
> There's a bit of an airworthiness issue involved here.
>
> The tailplane, like the rest of the structure is proven to take certain
> loads calculated from speeds and control surface deflection. In the case
of
> the tailplane/elevator, it's either 1/3 full deflection at max dive speed
> (actually around 1.1 x Vne) or full deflection at Va, whichever is the
> greater. So if the surface and its supporting bits are stressed for
these
> loads, then it should not be permitted to experience more than these in
> service, otherwise we're nibbling away at the safety margins.
>
> Roughly the load on the tailplane is proportional to its deflection. So
an
> increase from +4 deg. to +6 deg. results in a 50% increase in load.
>
> So you might break it off.
>
> Dave
>
>
> ----- Original Message -----
> From: <DJA727@aol.com>
> Subject: RE: Tailplane mass balance stops
>
>
> > A question,
> >
> > If you have a 6 degree travel at full deflection and 4 degrees is
> required, why would that be a problem? I would think that less that 4
> degrees would be a problem, not more. One problem I have dealt with is
the
> definition of the neutral point of the elevator. I have the required
travel
> up and down, but it really hinges (no pun intended!) on where you make
that
> point of zero degrees. One would hope to never actually hit that limit of
> travel unless in an emergency.
> >
> > Just wondering out loud.
> >
> > Dave Anderson A227
> >
>
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