What Chris describes is not at all unusual.  A number of aircraft fly better in 
an aft CG as the elevator gets too heavy with a forward CG.  A C-182 is a good 
example.  A 200 horse Muskateer is another.  It flies better and is easier to 
land if your CG is a bit aft simply because the elevator gets so heavy during 
landing when the CG is forward even though both configurations are still within 
the acceptable CG range.  Flying with a forward CG in these planes requires so 
much aft trim that the down force on the tail and trim drag is enough that the 
plane flies slower in a forward CG. 

The stock KR has so little stabilizer that an aft CG configuration can get very 
pitchy.  I flew my KR with the small tail for 500 hours before cutting it off 
and building a larger tail.  I've flown it another 650 hours since with the 
larger tail, so I think I can comment on this from a position of first hand 
experience.  After building a larger horizontal stabilizer and elevator, I 
really don't notice much difference in handling between a forward and aft CG in 
my KR as long as I stay within the 6" CG range as recommended by most builders.

I built the new stab and elevator to an 8' span using the templates Mark 
provides on his web site.

-Jeff Scott
Los Alamos, NM

> Could you go into further detail about "how" it flew better with a forward
> CG than an aft CG?

Sure, the plane under normal conditions (no baggage) would require
significant up trim to unload the stick, and when pulling power, would
drop the nose unless you held onto the stick. "Lawn dart"is a
description used more than once.

Conversely, with plenty of stuff in the baggage compartment (at or
near aft CG limit), the plane seemed to "float" in balance and handled
much better and was faster to boot. A pure dream to fly.

This was discussed often. It was considered by some to be good
practice to ignore the front half of the CG envelope.

It is possible that the CG envelope was shifted a bit forward than it
should have been and in fact I spoke with someone in good authority
that the aft limit was quite conservative and flying AT the published
aft limit would in fact produce good results, and it did.

> See http://www.n56ml.com/wb/index.html for more on the KR aft CG, which I'm
> pretty sure is common to most aircraft. This story should scare you...it
> certainly scared me!

I actually had read that last year, another well written piece and in
fact I am sure I saved it to PDF as well in my KR own knowlege base.

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