Weight limit discussion

[David Lockhart]

Gene,

Just my opinions -

So far as what flies best, reference the other post I made about wing
loading and power to weight ratio.

The only time adding weight to a plane makes sense and makes the plane fly
better is when the added weight results in eliminating inadequate structural
rigidity (stuff can be strong enough to not break, but weak enough to flex
enough to adversely affect performance).

I think we would both agree (as would Chuck, Bob, and many others on this
list) that IF the added $$$ were expended on the exotic goodies to reduce
the weight of a given plane (from 11.5 to 11, or 10.5 to 10), the plane
would fly better (and heck, maybe move from being illegal to legal).

Increasing the weight limit could allow you to not spend $$$ on your plane
and legally fly at the Nationals (worth noting the only planes that ever get
weighed at the Nationals are those that are likely to make the finals or top
few places).  And you could reasonably competitively fly the 11.25 or 11.5
lb plane against similar designs that are of legal weight (but I would
advocate that the vast majority of the time lighter is better).  BUT -
increasing the weight limit would only result in reduced costs in the short
term - in the long term it would cost you more if you want to remain
competitive because.

The top dogs have sub 10# planes for a number of reasons - they do spend the
$$$ on every lightweight goody they can find, and they have years of
experience that has taught them how to build light, assemble light, choose
the lightest components, etc (or contract/buy light for those top dogs that
don't build, which is actually the majority).  My two Vivats are 9.75 lbs
+/- 1 oz and I believe they are lightest Vivats in existence - minimal
paint, careful selection of components, and lots of time spent figuring and
designing minimal integrated structures needed to mount all the components.
Maybe the average builder would would build a pound heavier - in which case
they plane would close to, but under the weight limit.  The manufacturers
know a production plane needs to be able to be built by an average
builder/buyer under 11 lbs.  So making the Vivat any bigger than it is would
not be a very wise move by the manufacture with the current rules structure.

Change the rules - allow 11.5 or 12 lb planes.  It has been pointed out many
times on this list that the 2x2m size is not yet the limiting design factor.
Allow a higher weight, the top dogs will be flying bigger planes - which
will be heavier than 9.75 lbs, but still probably not 11 lbs.  And the
average guy building the plane will still build/assemble/accessorize at a
higher weight level - and no doubt some will exceed the new weight limit -
leading to another outcry to increase the weight limt, leading to another
full iteration of the cycle.  How many iterations will there be??  It all
depends on how quickly people in the event forget or ignore past history and
how shortsighted they are looking at unintended results of changing the
rules.

Right now you are flying an Aries, which we can agree is a competitive
airframe, even if slightly overweight (and again I think we would agree that
lighter is better).  Up the weight limit, and the bigger planes that take
advantage of the increased weight limit will render your Aries (at 11.5 lbs)
and my Vivat (at 9.75 lbs) just as uncompetitive against the new designs as
the Obsession, Hydeout, Elan, etc are today against the Aries (or my Vivat).
If the weight limit goes up, the plane of the top dog will get bigger and
more expensive, and so will the overweight less competitive plane chasing
it.

Think of it another way - and this is pretty easy to do.  Do a little
research on what the "average" and "top dog" setups would be for the variety
of 40, 60, 90, and 120 sized pattern kits and ARFs available today.  Maybe
even figure it out for 25, 27, 30, 33% etc. IMAC type planes.

The bigger you go, the higher the average cost.  I fail to see how the
average cost goes down by increasing the weight limit (because the planes
get bigger) given the time for the full effect of the change to be realized.
History of the event shows the average cost goes up (when engine
displacement allowed the planes to get bigger).  Completing an analysis of
the currently available designs and equipment shows the average cost is less
on smaller (lighter) planes.  Competitive nature predicts increased cost if
the weight limit is increased.

Dave

----- Original Message -----
From: Chuck Hochhalter
To: discussion at nsrca.org
Sent: Friday, February 25, 2005 10:22 PM
Subject: RE: Weight limit discussion






Funny Gene, I have the same dilemma, a 11.5 lb Aries and will have to spend
a few bucks to fly Nats if that is where this season takes me.

Someone earlier said that a plane doesn't make the pilot.  I agree to a
point but. here is the GREAT DISTRICT 6!!!  (couldn't help myself) we have a
ton of intermediate flyers who are great pilots and I personally believe
that they are so closely matched that equipment does play a part in how
competitive you can be.
I look forward to the challenge of flying against Mark, Martin, Jim, Errol,
Richard and others I know I have missed, what a great year it will be, and I
know that I can have confidence in my skills but also in my plane.

This is my first 2 meter plane, IMO to allow the lower classes a higher
weight range will allow those who are learning to build light, as it is an
art, and want to continue to progress up the classes, they will be able to
get to the 5kg limit using baby steps and not having to jump from whatever
they flew in sportsman to a 2 meter 11 lbs aircraft just to compete at NATS
for the FIRST time.

By the time I fly advanced, I am sure I will have started another plane, and
began investing more into my hobby and into pattern.
Once I have progressed to this point in pattern the likely hood to step away
from pattern is less and therefore worth the investment.

I hope this makes some sense, just a view from an up and coming pattern
pilot.

Chuck Hochhalter
District 6 Sportsman Champion 2004


-----Original Message-----
From: discussion-request at nsrca.org [mailto:discussion-request at nsrca.org] On
Behalf Of Gene Maurice
Sent: Friday, February 25, 2005 8:50 PM
To: discussion at nsrca.org
Subject: RE: Weight limit discussion

Dave,

I've got an 11½  pound Aries. To get it down to 5 kg will cost me hundreds
of dollars (carbon pipe, carbon tube, etc.). How does an increased weight
limit equate to costing me more? I'm not sure I understand this logic. How
and where will I spend MORE to add weight. Buy a gas engine? The gassers in
the size category we're talking about are substantially less $ than a DZ and
don't produce near the power my OS 160's do.

If the top dogs are building/flying at 10#, a pound below the limit, what
exactly will you do with another pound? Make their planes stronger and more
durable? Boy, that would be bad for everyone.

BTW, if heavier flys better, add lead, it's cheap.

Gene Maurice
gene.maurice at comcast.net
Plano, TX
NSRCA 877
AMA 3408

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