From reading Clarence Mather's A6 notes it seems that the idea of a 50%
stab area limit was based on the AMA's general rule that stab area over 50
% of the wing area must be considered as wing area. Since A6 was not an AMA
event for a number of years this rule was apparently never applied. When A6
was made an official event, a specific rule was included that specified
that there was no limit on stab area. This specific rule brought the AMA A6
rules in line with the unofficial rules that had been in effect for a
number of years.
My model, which is not actually a tandem but does have a very large stab,
has been flown at all but one Indoor Nats since 2006. It has never been
challenged as illegal. I have never seen an A6 with a VP prop. I have never
seen a biplane A6.
Some years back - and before A6 became an AMA event - a group of A6
competitors got together and came up with a set of rules they called the
"A6 National Rules". (I was not a part of this process) Below are the rules
and the included commentary. I believe these are nearly the exact rules
that were adopted when A6 became an AMA event. At a later date the plastic
covering restriction was lifted which made A6's easier to build to a
competitive weight.
Bill Gowen
*A-6 National Rules1. Maximum projected wing area 30 sq. inches. To
facilitate areaprocessing a dimensioned wing outline drawing with area
calculationsshall be provided to the CD.2. All wing, rudder & stabilizer
construction including wing &stabilizer posts shall be 1/16" Sq. minimum,
except ribs. Minimum ribsize shall be 1/32" X 1/16". Posts may be rounded
only in the area ofmounting tubes, if used.3. Propeller 6-inch maximum
diameter. Blades to be flat 1/32"minimum sheet wood, no forming (no twist
or camber).4. Maximum motor stick length 6 inches measured from the
thrustbearing face to the rear hook.5. Weight 1.2 grams minimum without
rubber.6. Covering: tissue, condenser paper, gampi. No plastic.7. No High
tech materials including boron, carbon, Kevlar and foam.8. Rubber powered
Comments (not part of the rules): Note that there are no restrictions on
the following: Tail boom dimensions Tail area Prop. Spar dimensions
Prop. Shaft dimensions Prop. Shaft material Bearing material Motor stick
dimensions other than the 6" rule. Also, laminated construction would be
legal.*
On Sun, Aug 21, 2016 at 8:08 PM, don_at_slusarczyk.com [Indoor_Construction] <
Indoor_Construction_at_yahoogroups.com> wrote:
>
>
> Bob,
>
> Actually Clarence Mather, the creator of A-6, wrote the following in a
> letter published in the 2002-2005 Winning Indoor designs in regards to
> tandems.
>
> " Perhaps it would have been better not to limit the area of the stab. As
> Dave suggests, tandems might be fun to experiment with. The added weight of
> the large “second” wing might cancel out the added lift, because the rear
> wing cannot produce as much lift as the front."
>
> Read his whole letter on page 9
> https://indoornewsandviews.files.wordpress.com/2012/10/
> winning-indoor-designs.pdf
>
>
>
>
>
>
>
>
Received on Mon Aug 22 2016 - 06:03:21 CEST