Technology and Paticipation

David Lockhart DaveL322 at comcast.net
Sun Jan 9 19:57:33 AKST 2005


John,

To further answer/evaluate the line of thinking you are on, current pattern rules have - no displacement limit on engines, a dimensional limit, and a weight limit.  With the current rules, the only real limit is the weight - so.......

How about a 30% Ultimate Bipe - give or take 70" span, 78" long, 1700 squ, and maybe 20 lbs???  Maybe one of the IMAC types on this list could do a reality check on my numbers - but I think the estimate is close enough for discussion purposes.

If you want to approach things from a "minimum" standpoint for weight - it is pretty easy - go back to several iterations in the rules - when the engine displacement was a 60 2C and weight limit was still 11 lbs.  Structural failures were rare.  Illegal planes were rare, and the ones that existed weren't competitive, so they attracted very little attention.

Regards,

Dave Lockhart
DaveL322 at comcast.net


  ----- Original Message ----- 
  From: John Pavlick 
  To: discussion at nsrca.org 
  Sent: Sunday, January 09, 2005 11:33 PM
  Subject: RE: Technology and Paticipation


  Troy,
   Good points. I understand what you're saying. Sorry, I'm an Engineer so sometimes I have a hard time explaining things that appear logical and obvious to me. All I was trying to say was that if we worded the rules so that "Weight - Ready To Fly" really meant what it said then you would weigh an electric with the batteries in it (charged) and a glow / gas plane with a full tank of fuel. The way it is now, it's open to interpretation - which fosters the type of behavior we see happening now. I'm not trying to start trouble, just make everyone think and be more careful when we draft and / or accept rules. In Engineering we work to a spec. When we're done with the first prototype, the design either meets the spec. or deviates from it in some way. This is all duly noted during the release process. When you write a spec. you try to accomodate Marketing's interpretation of the spec. This is called covering your a##. You have to make it immune to interpretaion as much as possible. This is to avoid working on weekends (when you should be at the field, not in the lab). Because of this, I've developed a fairly good sense of what will hold water and what won't. This rule doesn't hold water. When 3 people can read it and come up with the answer they want to hear, then it needs to be fixed / clarified. Here's some more "out-of-the-box" thinking:  What is the purpose of the weight limit? Safety I would think. Why is it a MAXIMUM limit. Lately it seems we're trying so hard to build BIG, light airplanes that some parts aren't strong enough (like wing tubes). In R/C car racing there's a MINIMUM weight rule. Since I don't think anyone purposely sets out to build a heavy plane, it just ends up that way (at least that's the problem I always run into) why do we even need a maximum weight rule. Maybe this works for "scale" models but I think it should be different for pattern planes. Lighter weight is an advantage. Maybe, if what you really want is light airplanes, have a MINIMUM weight rule. Everyone will try to work towards minimum weight. End result - same as with a max. weight rule BUT no more "unfair" advantages. Sure, some planes will be lighter than others, but none will be shaved to ribbons trying to be "legal". Does this make sense, or am I missing something? I understand that we're trying to keep things "safe" by limiting the amount of potential damage an 11 lb. airplane can cause when the wings fold, but...
  John Pavlick
  http://www.idseng.com
    




   -----Original Message-----
  From: discussion-request at nsrca.org [mailto:discussion-request at nsrca.org]On Behalf Of Troy A. Newman
  Sent: Wednesday, January 12, 2005 4:14 PM
  To: discussion at nsrca.org
  Subject: Re: Technology and Paticipation


    John et al,

    read this carefully. I'm not in favor or against any specific technology...But I think this point blow needs to be understood very well by us as a pattern community. Rules advantages to a given technology are a slippery slope. Regardless of the technology we choose to help out.

    Big thing in the current rules the battery is not the fuel. Its the fuel tank! The electrons are the fuel. So weigh with a  dead battery.

    I think that a case could be made that the current AMA rules could be interpreted either way. FAI has already set a standard in that Jason's models at the 2003 WC as well as those used at the Euro champ in 2004 were weighed with the Batteries installed.

    This is an interesting idea and I'm not taking a position on other to say what the rules are giving us. I think that opening up the weight limit for Electric only is not a very good idea. The reason is we are dealing with some limits. These limits help keep our sport in a price range and in a performance range. Allowing electrics to weigh without batts gives a huge advantage to the electrics. Right now the limiting factors for electric are weight...Batteries and motor combos. The power is equal to that of glow motors not more and not less EQUAL or as the NFL would call it parity...the battery technology right now is coming up short or just making the grade. The amount of power you can have are very dependant on the batts we can use. More power means more battery in today's technology an this mans the weight is higher 4P 8000mah packs vs the 3P 6000mah packs. But the weight limit is keeping the batts to a specific size and capacity. When the batts change and get lighter or more output the weight will come down. This will allow you to make weight even with the batts easier.

    If you blow the weight limit higher now you are driving more and more power in favor of the electric setup. This also drives costs. Example. Chip's DV bipe is a very big model. But with the opportunity to make weight without the batts...Chip now has a distinct advantage in using electric power. His wing loading is better being the bipe as he can carry 13 or 14 lbs with the extra wing. On the other hand a glow motor as it gets above a 140 to 160 becomes almost a problem in terms of fuel consumption vs power. Guys are complaining about fuel consumption rates now on the glow motors. This will drive people to gasoline...Not that Gasoline is bad...Just makes it now the advantage over glow. The result is you are now driving the guy that don't want electric away from glow over to gasoline.....So the glow systems are now the antiques.

    Then we change the rules to encourage glow motors to make a come back....We did this with 2 stroke vs 4 stroke. The 4 strokes have less power so let us give them extra cubes...60 2 stroke and 120 4 stroke. A couple years later 4 strokes have the advantage and we give the 2 strokes a boost...No engine limits just size and weight. Then the 2 strokes came back with more power....and the limits of 2M and 5KG means the performance of the models is way more than ever before and the rules evolve to make the flying harder rolling loops, circle and snaps. Now electric comes on the scene and gasoline too..The end result is a keeping up the Jones'


    Here is the JUST of my argument: So do we change the game again to encourage these technologies or do we keep the game the same and make the tools fit the game? We have already proven that an advantage in the rules will drive the technology to that as the preferred choice. If we keep the rules the same and make the technology come to us then the game is less effected and there are more choices to do the job. YS 160, OS 160, Hacker, ZDZ....Now everybody gets to play on equal footing...the game. No specific equipment is getting the granny clause because its tough to make the rules with it. It has been proven many times now that Electric is capable in both performance and rules compliant. Gasoline is also in the works and being ready to prove its mustard too. Glow is the preferred choice for now. I'm in favor of keeping the game the same and letting the guys that want the new technology to develop it to compete in the same game on the same field. Giving a hand out to one technology over another has in the past driven costs up, driven changes in the equipment and made the products we use even more and more specialized than they already are. This means decline in participation in my book.

    Gasoline and Electric are already Viable and has proven to work in the environment we already have. Yes perhaps your airframe choices are less if you choose electric or gas today..But there will be more and more for both gasoline and electric as time passes. The rules changes can't take place until 2007 regardless. In that 2 years today's models will be old news and something new will be in works like Hydrogen power models or something.


    Troy Newman
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