Alan Tolle wrote:

I am interested in the weight and balance figures reported by Ed Anderson in
the last post.   Here are some numbers for comparison.

My RV-6A (completed in 1991, 800 hours total time) Has a Lycoming 0360-A1A
with a long hub Hartzell constant speed prop.  The airplane has a full IFR
instrument and radio complement.  The aircraft empty weight is 1067 pounds,
or 103 pounds less than Ed's   The extra battery weighs about 23 pounds, but
I do not see how it could be possible that the rotary engine installation
could be 80 pounds heavier than the Lycoming.

The empty weight center of gravity is in exactly the same place in both
aircraft at 68.7 inches aft of datum, which is right on the forward edge of
the CG envelope.  This is OK because everything (except fuel) that is put
into the airplane takes the CG aft.

My gross weight calculations figure full tanks, 170 pound pilot and
passenger and 115 pounds of baggage.  (I know this totals 1750 pounds but
this is a cross country, no aerobatics number)  At this weight the aircraft
CG is 1 inch forward of  the aft CG limit.  (Ed's figure probably uses
somewhat less baggage.)  When the fuel burns off to 5 gallon minimum the CG
moves right to the aft limit.  It is this condition for which we have to be
alert --- full load of people and baggage, low fuel.  This is not so much of
a problem in the tricycle gear version.  However, in the tail dragger the
super light elevator greatly complicates the landing task, and  more than
one RV-6 has been lost due to this.

>From the beginning of RV kit construction the location of the battery has
been used to adjust the weight and balance.  It has gone everywhere from in
front of the firewall to just in front of the horizontal stabilizer way back
in the tail cone.

I am still curious about the 80 pound weight difference.  Guess I will have
to wait until I see the airplane.  Maybe Oshkosh.

 
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