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<DIV><FONT size=2>And they have quit improving glow engines?</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Didn't they just come out with a 2.0 ci glow engine thats
light enough to stick on a Pattern plane?</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Saying we can't do something because technology wil
advance means you must want to go back to the days when the Sig King Kobra was a
top of the line plane. Anything with higher performance than thhat had
using 1975 technology is not allowed.</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Glow planes DO bennefit from carrying more weight... you can
bolt on that 2.0 ci engine and carry a 30 oz fuel tank to feed it.... and
because you weigh empty you gain the bennefits of added power making the added
fuel weight inconsequential. Glow can compensate for the higher fuel
consumption that comes with higher power and not blink.</FONT></DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=Davel322@comcast.net
href="mailto:Davel322@comcast.net">Davel322@comcast.net</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=nsrca-discussion@lists.nsrca.org
href="mailto:nsrca-discussion@lists.nsrca.org">NSRCA Mailing List</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Thursday, June 21, 2007 12:09
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [NSRCA-discussion] Fwd:
Electric Weight Proposal Logic andRationale</DIV>
<DIV><FONT size=2></FONT><BR></DIV>
<DIV>Not a good proposal.</DIV>
<DIV> </DIV>
<DIV>The fatal flaw is this - Glow planes receive no benefit from carrying
additional weight. Adding weight to glow reduces the power to weight
ratio, carrying un-needed fuel detracts from performance. Adding more
battery weight to an electric could substantially increase the power output
AND power to weight ratio.</DIV>
<DIV> </DIV>
<DIV>Additionally, the proposal fails to acknowledge the inherent benefits of
electrics over glow (reduced structure is possible with reduced vibration,
reduced finish is possible with lack of oil...and many more).</DIV>
<DIV> </DIV>
<DIV>An additional flaw (conceptually) is that this idea is very
shortsighted. Electrics are still in their infancy. The motors,
batteries, and ESCs will all get lighter and more efficient (and cheaper) with
future develepment. Airframes tailored for electric will continue to
improve further reducing weight. Within the existing rules structure, a
very solid arguement could be made that electrics can already achieve equal
performance to glow, and a very solid arguement could also be made that a
cutting edge electric has better performance than a cutting edge glow.
Electrics do not need any additional advantages at this time and will be
dominant in the near future within the existing rules structure.</DIV>
<DIV> </DIV>
<DIV>An average flying weight for glow of 11.5 lbs assumes the average dry
weight is 11 lbs. 11 lbs is not the average dry weight.</DIV>
<DIV> </DIV>
<DIV>The assumption that 20 fluid oz is the average tank size needed for
completion of a pattern flight assumes a Masters or FAI preliminary
flight. Not all flights are for Masters and FAI. Substantially
less fuel is needed for Adv, Int, and Sportsman. Further, the assumption
would also seem to be based on a glow engine with a very high fuel consumption
ratio. Plenty of 2C setups complete Masters and FAI on 12 oz.....well
managed 4Cs do almost as well. Perhaps 14 fluid oz would be a better
average (~11 oz actual weight).</DIV>
<DIV> </DIV>
<DIV>The past few years, I've been fortunate to be flying some very high
quality composite models (glow Vivats and electric Prestiges). The
Vivats were 9 lbs 14 oz + 12 oz of fuel (more than enough for the Webra 160MC
to get through 1.5 PO7s) for an average flight weight of 10 lbs 4 oz. My
electric Prestige with TP5300s was 10 lbs even on the 2006 NATs
scale.....current configuration puts it at 10 lbs 3 oz. At ~$1900 USD
per copy, the Vivat and Prestige are not cheap, but hardly the most expensive
option. On the lower end of the price scale, there are plenty of options
from UltraRC, Fliton, etc, that can be well under weight electric or
glow. The Black Magic series is among the biggest planes currently and
recently available and can be built at 10 lbs electric and well under 10 lbs
glow.</DIV>
<DIV> </DIV>
<DIV>Applicable to this proposal (and others past, current, future) is that
the proposal should be evaluated from the perspective of a competitor looking
for a competitive advantage - ie, not how the proposal will effect current
equipment/desigsn, but what higher levels of performance could potentially be
achieved by a competitor looking to exploit the new rules. Historically,
any increase in size, weight, or displacement has resulted in larger and more
expensive airframes.</DIV>
<DIV> </DIV>
<DIV>Regards,</DIV>
<DIV><BR>Dave Lockhart</DIV>
<DIV><A href="mailto:DaveL322@comcast.net">DaveL322@comcast.net</A></DIV>
<DIV> </DIV>
<DIV> </DIV>
<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid">--------------
Original message -------------- <BR>From: Ron Van Putte
<vanputte@cox.net> <BR>I got the following from John Fuqua. He is
going to submit a proposal to increase the weight limit for electric-powered
airplanes to 11.5 lbs. I suggested to him that he "float" his rationale by
the NSRCA Discussion List, to get some feedback. Here is his response.
<DIV><BR class=khtml-block-placeholder></DIV>
<DIV>Ron Van Putte<BR>
<DIV><BR>
<DIV>Begin forwarded message:</DIV><BR class=Apple-interchange-newline>
<BLOCKQUOTE type="cite">
<DIV style="MARGIN: 0px"><FONT
style="FONT: 12px Helvetica; COLOR: #000000" face=Helvetica color=#000000
size=3><B>Date: </B></FONT><FONT style="FONT: 12px Helvetica"
face=Helvetica size=3>June 21, 2007 10:40:36 AM CDT</FONT></DIV>
<DIV style="MARGIN: 0px"><FONT
style="FONT: 12px Helvetica; COLOR: #000000" face=Helvetica color=#000000
size=3><B>To: </B></FONT><FONT style="FONT: 12px Helvetica" face=Helvetica
size=3>"Ron Van Putte" <<A
href="mailto:vanputte@cox.net">vanputte@cox.net</A>></FONT></DIV>
<DIV style="MARGIN: 0px"><FONT
style="FONT: 12px Helvetica; COLOR: #000000" face=Helvetica color=#000000
size=3><B>Subject: </B></FONT><FONT style="FONT: 12px Helvetica"
face=Helvetica size=3><B>Electric Weight Proposal Logic and
Rationale</B></FONT></DIV>
<DIV style="MIN-HEIGHT: 14px; MARGIN: 0px"><BR></DIV>
<P><FONT face=Arial size=2>Now that I am flying electrics I have come to
realize the penalty that electric planes have when being built that gas
planes to not have. That building penalty is significant under the current
rules. Electrics must be built lighter, to include paranoid attention to
everything used - wood, paint, fittings, etc., - all to make weight. Much
more of a concern than gas planes. Also I remember many instances at the
NATs when we were weighing airplanes, when the contestant was doing all he
could do to meet weight with a gas plane to include cleaning the fuel
residue inside and out. A lot of gas planes were weighing in at 10lb 11oz,
10lb 11.9 oz, even one that was only a few grams under 5 kilos. Then they
get to add a minimum of 16 to 20 ozs of weight by fueling up (and there is
no limit to fuel capacity). Takeoff weights are 12 lbs or more. This
situation seems bizarre and illogical when you put some thought into it.
Electrics have a finite weight and gas! planes are open ended at Takeoff.
Even though the 2005 NSRCA survey did not support an electric weight
increase it occurred to me that the survey did not offer any logic or
rationale as to why some increase would be justified or not. I have
attempted below to come up with a reasonable compromise on electric weight
allowance. I believe the rationale supports an increase but it would be
nice to have NSRCA membership look at it to find the fatal flaw in the
rationale before it gets submitted. The two paras below are taken from the
proposed change. Lets put it out and see what the discussion list comes up
with.</FONT></P>
<P><FONT face=Arial size=2>John</FONT> </P>
<P><FONT face=Arial size=2>Change paragraph 4.3 Weight and Size page RCA-2
to read: No model may weigh more than 5 kilograms (11 pounds) gross, but
excluding fuel, ready for takeoff. Electric models are weighed with
batteries<B><I> and are allowed an additional 8 ounces for a total of 11.5
pounds ready for takeoff.</I></B><I></I> No model may have a wingspan or
total length longer than two (2) meters (78.74 inches).</FONT></P><BR>
<P><B><FONT face=Arial size=2>Logic behind proposed change, including
alleged shortcomings of the present rules. State intent for future
reference.</FONT></B> </P>
<P><FONT face=Arial size=2>Today’s 2 meter RC Aerobatics fuel powered
aircraft typically use fuel tanks with a 20 fluid ounce capacity. A 20
fluid ounce Crank Tank containing 25% Cool Power Pro Pattern fuel was
tested. The fuel weighed 17.3 ounces. Allowing for variation in tank sizes
and fuel type a conservative weight of 16 ounces of fuel on average seems
appropriate. This means that an allowable takeoff weight for fuel powered
aircraft is at least 12 pounds. Assuming that all fuel is consumed during
the flight, the average weight for the aircraft is 11.5 pounds. By
restricting electric powered aircraft to the takeoff weight of unfueled
aircraft an unfair weight penalty is being arbitrarily imposed against the
electric model. By allowing electric aircraft an AVERAGE flying weight of
the fuel powered aircraft, flying weight equity is
restored.</FONT></P></BLOCKQUOTE></DIV><BR></DIV></BLOCKQUOTE>
<P>
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