"Koopas Ly" wrote in message
om...
I would think that the only source of increased drag from a forward
c.g. condition is profile drag due to a more nose-up elevator trim tab
or elevator.

There are several factors that translate into increased drag:

* Drag from the trim, if used (as you noted)
* Drag from the elevator itself (as you noted)
* Increased induced drag from the horizontal stabilizer/elevator due to
increased lift on that airfoil
* Increased induced drag from the wings since the increase in lift on the
horizontal stabilizer translates into added weight for the aircraft, which
has the exact same increase in induced drag that adding physical weight to
the aircraft would have

How do you see a forward c.g.'s extra drag translating into premature
airspeed bleeding? Sink rate and angle of descent would
increase...but airspeed?

I'm not sure I understand your question. Is this a continuation of the "why
is there increased drag?" question? Or are you asking, even if one assumes
increased drag, why does the airspeed bleed off quicker?

If the former, I hope my earlier bullet points answer your question. If the
latter, that should be obvious. For a given configuration, deceleration is
strictly related to the net difference between thrust and drag. When thrust
is greater than drag, you accelerate. When thrust is less than drag, you
decelerate.

Furthermore, the rate at which you decelerate is directly proportional to
that net difference. For a given thrust, more drag means a greater rate of
deceleration. Moving the CG doesn't affect thrust, but it does affect drag.
Moving CG forward increases drag (as noted above) and thus increases the
deceleration rate.

Pete