Anderson Ed wrote:

I agree with Alan, that getting that 100lbs trimmed down is a goal to
shoot for. Not having the resources nor spending the time that Evert
Hatch had in developing the 13B for aircraft use, I am actually fairly
please that the installations are as close as they are.  Also, not
knowing the configuration of the -3,-4 of Evert's makes it somewhat
difficult to compare and draw lessons on where improvement is feasible
given the limited resources of most builders.  My assessment based on
limited knowledge is that Evert's configurations probably saved weight
in the areas of the PSRU, exhaust system and intake system and probably
the coolant system over my FWF configuration.

 However, feasibility is certainly a constraint and basically that means
$$.  Best I recall was that Evert's PSRU would have cost in the vicinty
of $7500 compared to $2000 ($2500 currently) for my Ross PSRU, so don't
know what that would have worked out to $/lb, but $7500 would have
priced it out of my range.

 I estimate I could pair down approx 25-50lbs over my current weight,
but would have to stretch beyond that. Just so much you can do with the
configuration you have.   A future goal of mine is a complete
reconfiguration of the FWF including the motor mount, exhaust/intake
systems and coolant systems.  Some things were simply driven by the
under the cowl configuration which was my case was largely dictated by
motor mount braces and space under the cowling.  So as the good ideas
keep coming in, I have a reference file stuffed with all the good
suggestions many have made.  One that I will avoid, however, is any
requiring airframe modifications (such as the P-51 scoop) as just too
uncertain of the overall airframe/performance impact.

Keep those suggestions rolling in, next configuration will incorporate a
number of them.

Ed Anderson

Paul wrote:

I don't think you need the P51 scoop with an RV6. I think Jim Mosur's
configuration would work fine.

Other than the obvious, such as light weight alternators and starters
you could run the light weight rotors with lighter weight balance
weights. Perhaps Everett was doing that.

Paul Lamar
 
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