A weighty situation

[Gerald Arana]

My .77 needs 2,8oz per flight Bob.. L

This I gotta see! 

Jerry

[Doug Moon]

Goodness,

There is a lot of heat over something which can be handled simply which would affect all gas flyers equally and with a fair approximate weight not too far from actual weight.  Simply add one ounce for each .10 of displacement to the scale weight of the airplane. My F-51,s would add 6 ounces to its scale weight.  My Bearcats and Critical Mass would add 7 ounces to their scale weight.  Fox .35 airplanes would add 3 ounces and so forth.

Al

That’s a good idea. Simple and straight forward.

[Brett Buck]

There is a lot of heat over something which can be handled simply which would affect all gas flyers equally and with a fair approximate weight not too far from actual weight.  Simply add one ounce for each .10 of displacement to the scale weight of the airplane. My F-51,s would add 6 ounces to its scale weight.  My Bearcats and Critical Mass would add 7 ounces to their scale weight.  Fox .35 airplanes would add 3 ounces and so forth.

    Yes, that would be a potential "solution". That of course presumes that there is a problem to solve in the first place (which, given the other tolerances, there isn't). And as soon as you did that, the people who are worried about the problem will want to either measure everyone's engine (he said it was a 46 but it's really a 75), and/or argue that 7.5 ounces is not enough for a 75, since David runs about 8.5 ounces in his, not 7.5.

   If this was a real safety issue, then it might be worth considering, but when you have the same airplane being weighed from 62 ounces to 67 ounces (which is the range I have gotten over the last few year (and its really 66.5)) and using a rusty fish scale with a calibrated eyeball deciding when to release the pull, these variations are all in the noise. To significantly improve it you would need some sort of calibration program for the measuring equipment, which we don't need to do nor are we going to do.

   This is more about the electric fliers feeling aggrieved over having to weigh with the battery in. A simpler solution would be to allow them to weigh the airplanes without the battery, and counting on the margin to cover the difference. I am not sure what Frank has in mind for a "reasonable" pull test, but his point is that 10G is too much. Leave out the battery, and it's 7.5gs or something for electric, and about 1.6x over the flight loads instead of the (by design) 2x. I can live with that, it's not like IC airplanes are flying off the ends of the lines with an *actual* 1.7x (once you add 8 ounces of fuel).

     Brett

[Tom Luciano]

Im looking at this in a little different perspective, as I see a tie with the Ukraine line thread. My electric plane comes in at 63.5 oz ready to leave the ground. Im waiting for the one time im weighed in and im over.  So, Im Flying the 4 strand 016 lines. The day i come in overweight my lines are now illegal.  Yet, the guy with the IC engine that weighs 62 oz.dry, fuels his plane and takes off at 67 oz legally with 016 lines. Thats my issue. I couldnt care less if  me or  IC Joe pulls an extra 5 pounds .
My 2 cents
Thanks

Tom

[Charles Carter]

It is 2018 and we are still using stainless steel wire?  How long has stainless steel wire be around?  Didn't we at one time use wooden bellcranks connected to stainless steel wire?  If you have noticed we don't use wooden bellcranks anymore but we are still using stainless steel wire. We have modern and sophisticated model airplanes connected to old technology.  Do you realize all the technological gains made in fishing line industry?  If we used modern technology to connect to our handles and airplanes we all could benefit from using thinner and better lines.   Wouldn't the “line break” point be elevated to the point where both IC and electric models could both be flown on the same thin lines because there actual take off weight would be well below the “line break” of the same thin lines?

[Joseph Daly]

Although I am new to stunt, I do not understand why we would not have the same playing field? To me it should be equal. I did like Paul’s idea about adding weight to equal the playing field. This is much like NASCAR they make all the cars weigh the same and in the top series’s they also figure the weight of the driver so that they level the playing field. The lower ranks they simply weigh the car with the driver in it and make all cars equal for the most part. This is just my opinion, I agree with what Bob is trying to do and I think it is the right thing to do.
Thanks
Joe

[Dave_Trible]

I would be more in favor of weighing/pulling the electric battery free, or a little less knowing we have a substantial safety factor built in.  I have nothing under 70 ounces and always use .018 and always feel like I need to tie my butt to a tree to pull the planes.  It will take it for sure but I can't see having to pull any more when it has nothing to do with me.  I'd rather make whatever adjustments the other direction.

Dave

[frank williams]

   I would be curious what you would consider a pull that is not excessive.

 But I think that the idea that you are shooting for 63 ounces or whatever so you can use .015s  is not much of an argument - although I won't be rushing to stop anyone from shooting themselves in the foot that way.

     Brett

I don ‘t necessarily feel that 10 g’s is too much, but ten 10 g’s with also an imposed  “stair step” line diameter minimum  is over specified I feel.  The “stairstep” diameter specification is a remnant of the previous ic rule.   Nominal flying g’s are 3, a runaway ic is probably about 5 g’s.   Simply a 10 g pull is satisfactory.

At present I’m shooting for 63 oz’s …. Yes, not so much to use 0.015 stranded, although some planes will tolerate them, but to take advantage of the 0.012 solids.   10g pull before you fly and you’re ready to go.  Maybe a =/- delta for ic/elec if needed.

[Brett Buck]

At present I’m shooting for 63 oz’s …. Yes, not so much to use 0.015 stranded, although some planes will tolerate them, but to take advantage of the 0.012 solids. 

   .012 SOLIDS!  Wow, that is not something I would have contemplated as an issue.

   Brett

[Brett Buck]

It is 2018 and we are still using stainless steel wire?  How long has stainless steel wire be around?  Didn't we at one time use wooden bellcranks connected to stainless steel wire?  If you have noticed we don't use wooden bellcranks anymore but we are still using stainless steel wire. We have modern and sophisticated model airplanes connected to old technology.  Do you realize all the technological gains made in fishing line industry?  If we used modern technology to connect to our handles and airplanes we all could benefit from using thinner and better lines.   Wouldn't the “line break” point be elevated to the point where both IC and electric models could both be flown on the same thin lines because there actual take off weight would be well below the “line break” of the same thin lines?

    GSUMP lines are something being experimented with in other venues, so far, no one has proposed them for stunt (along with the necessary engineering evaluation) and termination requirements. I don't know enough about them to do it myself.

     Stainless steel stranded lines have the advantage of 70-ish years of experience with very-well-understood characteristics. That is not irrelevant to the discussion.

   Brett

[Rick_Huff]

Seems to me that this issue is mainly centered on the line diameter requirements.  I agree with Brett that a few pounds, more or less, in the pull test doesn’t matter very much.  However, the line diameter requirement does have an effect on the way the plane flies.  Whether you like the reduced drag of smaller diameter lines or the stiffer more responsive feel from larger diameter lines, shouldn’t it be left up to the pilot to decide what they like?

Rick

[Randy Cuberly]

Seems to me that this issue is mainly centered on the line diameter requirements.  I agree with Brett that a few pounds, more or less, in the pull test doesn’t matter very much.  However, the line diameter requirement does have an effect on the way the plane flies.  Whether you like the reduced drag of smaller diameter lines or the stiffer more responsive feel from larger diameter lines, shouldn’t it be left up to the pilot to decide what they like?

Rick

Yes, especially if the smaller diameter lines are stronger (or just as strong), and stretch less as in the case of some of the currently available stuff!

Unfortunately, most safety provisions while suggested by engineers are most often decided by lay politicians!

Randy Cuberly

[Trostle]

Point taken, Lauri! 

Bob

Bob,

Have you ever seen one of Lauri's engines.  They are a masterpiece of machining and they run extremely well.

Keith

[Dan McEntee]

One thing that is lost in this discussion, is that , yes, an IC model takes on 4 to 8 ounces of fuel for take off, typically. But as soon as the engine is started, that weight starts coming off and continues to come off until the end of the flight. Electric models weigh the same throughout the flight. Yes, that is all very obvious but I'm gonna guess that whoever was involved in the new pull test rules took that into consideration. When does everyone think that the most stress is on the lines, the beginning, middle or end of the pattern?  Some may say that the most stress is in the latter half of the pattern after the triangles, and by that point, about half the fuel/weight or more is gone. When it comes to the idea of fairness or who has an advantage, I would say it is all in the electric court. They can build a model that weighs the same and balances the same throughout the flight. I think that would kind of "balance" against having to pull a few pounds more. Some where in the concept of trying to get an electric model weight down to where you can use smaller diameter lines is the right size/wing area/wing loading to achieve that. The answer to that question may lay entirely in a new model design to best use the consistent dead weight that is the electric power plant. So far, most people are just converting existing design with slight modification to mount the equipment. With as much success that the electric stunt model has had, I feel that there is no disadvantage to the extra weight. You just have to learn to work with what you have and design an air frame to give you want you want, not just "build a lighter model." I hope that makes sense.
    Type at you later,
   Dan "Gimme My Nitro" McEntee

[Ken Culbertson]

Seems to me that this issue is mainly centered on the line diameter requirements.  I agree with Brett that a few pounds, more or less, in the pull test doesn’t matter very much.  However, the line diameter requirement does have an effect on the way the plane flies.  Whether you like the reduced drag of smaller diameter lines or the stiffer more responsive feel from larger diameter lines, shouldn’t it be left up to the pilot to decide what they like?

Rick

I agree 100%  The pull test should be the qualifier and you should be able to fly on sewing thread if it will pass the pull test.  I for one would like to see a bit more lbs added to the test.  When these big heavy planes lose tension overhead and hit the lines on the other side of the circle they pull a whole lot more than any pull test.  Why do you think we have to wear that sill noose around our wrists.  Most everything I fly has a floating bellcrank and properly mounted it can take double the required test.  I say up the pull test and drop the line size requirement entirely but that's just me and I could be wrong!

[Brett Buck]

This I gotta see! 

    That is perfectly plausible, he is using very advanced techniques to maximize the specific output, and can do it because he is building the engine from scratch. I also expect that he is running a very efficient propellor.  We take existing engines and figure out how to make them run, and sometimes that means using very inefficient systems and just building a bigger fuel tank.

    Brett

[Steve Helmick]

While I really don't care even a little bit about making it either "fair" or "equal" for electron burners, I am somewhat shocked that you all seem to agree and accept that one fluid ounce of high alcohol content fuel would equal one ounce of weight. It seems to me like the proposal is for one fubar to replace another fubar in the rules. Since I have no idea how much your battery measures in fluid ounces...leave it alone.  Steve













 

[Dave_Trible]

While I really don't care even a little bit about making it either "fair" or "equal" for electron burners, I am somewhat shocked that you all seem to agree and accept that one fluid ounce of high alcohol content fuel would equal one ounce of weight. It seems to me like the proposal is for one fubar to replace another fubar in the rules. Since I have no idea how much your battery measures in fluid ounces...leave it alone.  Steve

Steve our methanol is something like .82 oz. weight per ounce fluid-less oil.  For discussion purposes it's close enough 1-1. What is strange about that is I can readily feel 1/2 oz. of lead nose weight on the planes.  I don't seem to notice losing 7 oz. in the nose while I fly.

Dave

[Brett Buck]

While I really don't care even a little bit about making it either "fair" or "equal" for electron burners, I am somewhat shocked that you all seem to agree and accept that one fluid ounce of high alcohol content fuel would equal one ounce of weight. It seems to me like the proposal is for one fubar to replace another fubar in the rules. Since I have no idea how much your battery measures in fluid ounces...leave it alone.  Steve

     I was figuring about 6 ounces for my 7.1 ounce tank, which seems pretty close to me.

     Of course, if you accept the concept that the tolerance stackup leads to about a 5 lb tolerance in the actual pull test, the difference is completely lost and moot.

     Brett

[Brett Buck]

Steve our methanol is something like .82 oz. weight per ounce fluid-less oil.  For discussion purposes it's close enough 1-1. What is strange about that is I can readily feel 1/2 oz. of lead nose weight on the planes.  I don't seem to notice losing 7 oz. in the nose while I fly.

     Try doing the hourglass first.

      One of the things I notice when flying Classic airplanes, even with 4 ounces of fuel, they go from too sluggish to too sensitive from beginning to end because the tail volume is so small.

      Brett

[Dennis Adamisin]

I think we did the right thing a few years back when we retired the pull test based on engine displacement and introduced the pull test based on model weight.  However, we ALSO  defined minimum line sizes at different weight points. 

The point that Bob made in his original post was essentially that we did not quite complete the deal.  The criteria we use for weighing electric models makes perfect sense.  We would have an awful hard time explaining to a third party why we would not treat an IC airplane by the same criteria. 

However, I want nothing to do with bringing fueled models into the "180" building for weighing!

Since our minimum line sizes and pull test are based on weight, there is an opportunity to simply use DIFFERENT weight tables to drive the minimum line size requirement.  I suggest using the current weight schedule for electric models with batteries installed and use a different (lighter) weight schedule for IC powered models with empty fuel tanks.  To show how that would work I prepared the example below, based on modifying the table we have in the rule book.

We could argue (discuss) whether the weight differentials correct, but I think something in this format is a workable solution that would be easy to administrate.  NOTE: had a devil of a time getting column alignments - please pardon the mess!


  Electric Powered            IC Powered                  Required Minimum Diameter of Each Line                      Pull Test
w/Battery Installed   w/Fuel Tank Empty                Single Strand              Multi Strand           
      (ounces)                (ounces)                        1 Line   2 Lines                 2 Lines                  Electric                     IC Powered
---------------------   ----------------------             -------     --------              --------                  ---------        ------------------------------------------
       0 - 14.0                   0 – 12.0                      0.014"    0.008"                 0.008"                   10 g             10g based on model weight plus 2 oz
   14.1 - 40.0             12.1 – 36.0                       0.014"    0.010"                 0.012"                   based on       10g based on model weight plus 4 oz
   40.1 - 64.0             36.1 - 58.0                       0.014"    0.012"                 0.015"                   model           10g based on model weight plus 6 oz
   64.1 - 80.0             58.1 - 72.0                       0.016"    0.014"                 0.018"                   weight          10g based on model weight pus 8 oz
   80.1 - 123              72.1 - 113                        0.021"    0.018"                 0.021"                                       10g based on model weight plus 10 oz

I admit the weight differential would over-compensate for the fuel load on Lauri's magnificent engine! 

[Randy Cuberly]

It would seem that the airframe on and electric airplane, especially the fuselage could be build significantly lighter than on an IC airplane.  There is far less vibration stress on the airframe.  Wood in the fuselage could be thinner and even lighter.  I would think less hardwood and plywood would be required.

I know for a fact that a couple of the nicely finished electrics here in Tucson weigh less than some of the similar sized IC airplanes.  That would mean that the airframes would have to be very light.

John Callentine's 650 sq in electric for instance weighs 61 oz with battery installed.  most of the similar sized IC planes here weigh at least that much with no fuel on board!

Or am I all wet about this!  I have very little real electric experience but it just seems logical that they could be built lighter!

Randy Cuberly

[RandySmith]

One thing that is lost in this discussion, is that , yes, an IC model takes on 4 to 8 ounces of fuel for take off, typically. But as soon as the engine is started, that weight starts coming off and continues to come off until the end of the flight. Electric models weigh the same throughout the flight. Yes, that is all very obvious but I'm gonna guess that whoever was involved in the new pull test rules took that into consideration. When does everyone think that the most stress is on the lines, the beginning, middle or end of the pattern?  Some may say that the most stress is in the latter half of the pattern after the triangles, and by that point, about half the fuel/weight or more is gone. When it comes to the idea of fairness or who has an advantage, I would say it is all in the electric court. They can build a model that weighs the same and balances the same throughout the flight. I think that would kind of "balance" against having to pull a few pounds more. Some where in the concept of trying to get an electric model weight down to where you can use smaller diameter lines is the right size/wing area/wing loading to achieve that. The answer to that question may lay entirely in a new model design to best use the consistent dead weight that is the electric power plant. So far, most people are just converting existing design with slight modification to mount the equipment. With as much success that the electric stunt model has had, I feel that there is no disadvantage to the extra weight. You just have to learn to work with what you have and design an air frame to give you want you want, not just "build a lighter model." I hope that makes sense.
    Type at you later,
   Dan "Gimme My Nitro" McEntee

My 60s sized  ships  use  just under 5 ounces for the  VECTRA  and  just over 5 ounces  for the KATANA , average that weight it is  2.1/2  ounce . I think t s funny so many people think we all are using  7 to 8 1/2 ounces of fuel,  and some want to add a minimum of 6 ounces to your  IC plane?
I agree  if we fly the  2 type planes together  the field should be level,  HOWEVER  as I have been told  by several people flying Electric,  they have a  huge set of advantages over  IC  as it stands  now.

Like the advantage to start the motor and the pattern,  Big one for Electric

Run time,  big advantage when you can get every flight almost to the second, advantage electric

Program the computer controlled motor to help you with certain maneuvers, like a burp, followed by 5 seconds of FULl Blast power to increase the speed to help with placing the plane better where you want it on landings.

Being able to programs in more or less simulated 4/2 break  instantly.

Being able to have the motor shut itself down automatically if you hit  the  prop on the  ground on takeoff

There are several more  but the point is made, and not to mention being able  to get much more practice at many more sites.  And  there is  NO telling  what else people will be  doing  in the future ,with computer controls to help fly your maneuvers

 I develop, sell, planes and equipment for both systems, and  I would  not want  one to have more advantages over  the other, no matter  what is motivating the plane.  In my mind all is  NOT level  now.

Randy

[Brett Buck]

I agree  if we fly the  2 type planes together  the field should be level,  HOWEVER  as I have been told  by several people flying Electric,  they have a  huge set of advantages over  IC  as it stands  now.

Like the advantage to start the motor and the pattern,  Big one for Electric

Run time,  big advantage when you can get every flight almost to the second, advantage electric

Program the computer controlled motor to help you with certain maneuvers, like a burp, followed by 5 seconds of FULl Blast power to increase the speed to help with placing the plane better where you want it on landings.

Being able to programs in more or less simulated 4/2 break  instantly.

Being able to have the motor shut itself down automatically if you hit  the  prop on the  ground on takeoff

     I more-or-less agree with this assessment, and to me it is clear that the advantage will grow with time and experience. We have about 70 years of IC engine experience, and 30 with the definitive and probably final configuration. They are more-or-less optimized at this point and at least a fair number of people are able to achieve nearly ideal performance most of the time.

    Having said all that, I still think that IC in perfect shape has advantages over electric in the current state of development in a few conditions, specifically, heavy but smooth wind. Electric has advantage in most other conditions, particularly light to dead air, or light turbulent air.

      I don't think the rules should drive you to a solution, but at the  same time, if something its better, it's better, and trying to change the rules to even up the odds by favoring one over the other is something I wouldn't have much enthusiasm for. Electric is not the sort of leap forward that happened when we went from ST60s and the like to tuned pipes, and we didn't change the rules to try to help them keep up (or as Windy suggested, start a different event to separate them out).

       The issues discussed here are really just about feeling aggrieved, with some justification, but don't make any difference from a competitive or engineering standpoint. It's not really worth fixing, but by the same token it doesn't hurt anything if they are "fixed".

     The line size requirements don't make a lot of sense a long as we are weighing the models and pulling 10gs. and if we can, we should get rid of them. Last time I broached the subject, I was told they would never go away, but maybe that has changed.

     Brett

[roy cherry]

good morning  i have been following this thread as i wait for ome weather to go testing my latest model  i fly f a i so if you pass the pull test you can use any size line you care to but what  causes me some concern is that only oficciall flights are pulled for a pull test to be valid every flight at a contest ought to be pulled including all test and practist flights if their are any safty concerns  other wise to me it seems pointless        roy   

[RandySmith]

As I wrote  earlier, I think this is  much ado about  nothing,  just let  people pull 10 gs  and  run whatever lines they want, as long as they test OK
Simple solution, it will  work, and  gets us past calling  IC guys bullies, and  insinuating they are liars , that  we DO NOT need, and  does  not serve  us well

Randy

[frank williams]

Without a doubt this is a simplest and best solution to the problem at hand.  10g pull only.

[frank williams]

I disagree.  In general people are smarter than you think.  FAI flyers don't seem to have a problem.

[RandySmith]

I disagree.  In general people are smarter than you think.  FAI flyers don't seem to have a problem.

Yep  this is right the rest of the world has been doing this for many years, and you will not find anyone flying a 64 ounce ship on 008s, I think  you would be  hard pressed to find one flying on 012s,   Even  015s  are  lines I personally would not use on a  64 ounce  60 sze ship, too spongy, better control and feel  is  much more important  than the .003 difference, and if you have to , you can run 014 solids. 
I do not think  008s  would even  pass the 10 G  pull test,  and  if you are doing 10 G pull test, then your lines break while flying pulling 3 Gs, something  else seems  wrong

Randy

[Dave_Trible]

In all my time in this sport, the very few failures I’ve seen were all, save one, were where the wire got damaged,  mostly where the ends were made by either working back and forth at a hard point where the cable exits the ferrule or a kink.  The only other failure was a brand new set of Sullivan’s from years ago shredded in the middle on the first flight- an obvious flaw in the cable.  The line weight really wouldn’t have mattered very much other than the heavier line will hold with more damage not yet seen.  Line condition I think is more important than weight.  You can only hope a pull test will find the weak point on the ground.

Dave

[Steve Helmick]

Brett you may not be aware of this per your comment but Gsump lines have been submitted by Tom Hampshire for a rule change to allow for the use in CLPA on 5/2/18. Proposal and initial vote links. Looks like it passed initial vote 6 to 5.  https://www.modelaircraft.org/files/CLA19-02.pdf  https://www.modelaircraft.org/files/CLAerobatics2018InitialVoteResults.pdf    Dennis Adamisin, Bob Hunt, Phil Cartier, and Frank Williams also signed the proposal.

"Gsump lines"?  I assume you mean Spectra or MicroDeema fishing lines, but I've never heard those referred to as "Gsump". I have not tried either, but I know there is some information in the AMA rulez about how they are to be fastened at the end....but there have been reports that it doesn't work. I figured that there would need to be some improvements in the rules there before further applications would be allowed. But maybe I figured wrongly.    Steve

[mike londke]

I apologize for posting bad info. I didn’t look at the date close enough. It appears this proposal was dropped. So I deleted the post.

[Brett Buck]

In all my time in this sport, the very few failures I’ve seen were all, save one, were where the wire got damaged,  mostly where the ends were made by either working back and forth at a hard point where the cable exits the ferrule or a kink.  The only other failure was a brand new set of Sullivan’s from years ago shredded in the middle on the first flight- an obvious flaw in the cable.  The line weight really wouldn’t have mattered very much other than the heavier line will hold with more damage not yet seen.  Line condition I think is more important than weight.  You can only hope a pull test will find the weak point on the ground.

    Right - we are hardly treading new ground here. This sort of issue is a common one in the aerospace industry - trading off increased safety/margins for performance. You can't build spaceflight pressure vessels to the same margins as a stationary steam boiler, for example.

    I think that the line pull test/line size requirements follow common safety factor rules for performance (roughly a factor of two after a single failure) and that's a good standard to use in this case. The previous chart had some real anomalies, in both directions, so the latest change was to even that up. It just happened that the most critical break point fell right in the middle of the current range of airplane weight at 64 ounces. That's what the engineering said, so that's what it is.

     If people are willing to move past the requirement (apparently mandatory in the past, maybe not mandatory now) line size requirements, then the issue essentially goes away - from an *engineering* standpoint.

     I dispute the "fairness" aspect as it appear to have more to do with looking bad to some people for some reason. Weigh the airplanes with or without the battery or fuel, you are barely affecting the safety due to the other tolerances in the system, and if if makes someone feel better to say the airplane weighs 55 ounces than 64, then fine with me. It's entirely cosmetic, and if someone is all hot to fly their 60-sized electric at a liftoff weight of 64 ounces on .015 stranded, or .012 solids, breaking loose and hitting someone is not the biggest issue.

     Brett

[Ken Culbertson]

Just out of curiosity, has anybody ever devised a method of measuring line pull in the air?  Other than combat I have only seen two in flight line failures and both of them had just passed a pull test.  We pull both lines together yet the "ah sh**" situation usually hits one line full force.  If you don't break a line you sure do put a lot of stress on the bellcrank and flap horn.  I am sure there is a reason but why don't we use "stops" on the bellcrank to limit movement if one line is yanked.   How many of our ships could stand the pull test if each line were done separately, even at lower lbs.

[Jim Svitko]

I have also been curious about measuring the line pull in the air.  With the proper equipment (instrumentation?) I suppose it could be done if someone wanted to go thru the steps.  But, is it worth the time spent?   Maybe, for some, but for me, it is easier to do the math.  I know the weight (mass) of the plane, the radius of the circle, and with a standard lap time (5 seconds, give or take a few tenths?), I plug the numbers into the formula.

[Trostle]

I apologize for posting bad info. I didn’t look at the date close enough. It appears this proposal was dropped. So I deleted the post.

No need to delete your post.  The basic proposal to allow GSUMP lines (spectra) did pass the initial vote of the Contest Board 6-5, where a simple majority is needed to pass the initial vote.

Keith

[Randy Cuberly]

Just out of curiosity, has anybody ever devised a method of measuring line pull in the air?  Other than combat I have only seen two in flight line failures and both of them had just passed a pull test.  We pull both lines together yet the "ah sh**" situation usually hits one line full force.  If you don't break a line you sure do put a lot of stress on the bellcrank and flap horn.  I am sure there is a reason but why don't we use "stops" on the bellcrank to limit movement if one line is yanked.   How many of our ships could stand the pull test if each line were done separately, even at lower lbs.

A stop on the bell crank wouldn't limit the force on the line when it hit the stop.  It would simply make it occur sooner...and possibly more often!

Further, if one line breaks when it hit the end of travel the other usually does NOT.  I have see stunt planes do a dozen or more loops on one line before crashing or in a couple of cases run out of fuel!  Of course if it's the up line that breaks there is probably not enough time left before the crash to even blink....still NO flyaway!

I'm of the opinion that all of this is a non problem but would be highly in favor of a simple pull test requirement like the FAI has...If it passes the pull test...It flies!  Simple and effective in my opinion.

In other words a line diameter requirement is unnecessary.  If you can find lines that are strong enough to pass the pull test requirement why should anyone besides the pilot care if they stretch, etc, etc, etc...

What's next lines can't be too shiney because they'll blind the pilot or judge...

Randy Cuberly

[Ken Culbertson]

A stop on the bell crank wouldn't limit the force on the line when it hit the stop. 
Randy Cuberly

I was thinking more in line with damage to the rest of the control system if there is no practical limit on bellcrank movement.  You are right about the 2nd line not usually breaking but once the loops start there is little or no centrifugal force to break it.  There is however a very valid reason to keep the line size rules.  Without stupid rules like that one to argue about we would have to do something constructive.  My vote goes to pulling the "cr**" out of the plane then fly on the lines you did it with, even if it is dirty kite string.

[peabody]

I've been pondering......
A tuna piped IC set-up weighs around a pound (or more) when all is said and done....
I was told that an electric motor of similar power weighs 6 ounces....and a battery that is probably too much weighs 10 ounces....
Same same water buffalo....

EXCEPT that batteries are always getting lighter.

Who has the advantage?

[Randy Cuberly]

I've been pondering......
A tuna piped IC set-up weighs around a pound (or more) when all is said and done....
I was told that an electric motor of similar power weighs 6 ounces....and a battery that is probably too much weighs 10 ounces....
Same same water buffalo....

EXCEPT that batteries are always getting lighter.

Who has the advantage?

Yeah and don't forget the empty fuel tank weighs up to about 1 3/4 oz.

Personally I believe that on the larger competitive setups on both sides the difference is insignificant with possibly the advantage going to the electric!  In fact I think I pointed that out, with the actual weights, in a previous post that received NO comments!

Plus the fact that it's easier to build an electric lighter since the vibrations loads are much lower on the fuselage!

I'm beginning to believe that we are being Conned guys!   

Whatever happened to common sense?

Randy Cuberly

[Gerald Arana]

Whatever happened to common sense?

Randy Cuberly
[/quote]


It went out with the Obummer administration! 

Jerry

PS: What's common cents? 

[peabody]

Yup Randy...the con is on.....
Checked weights (WITH Battery v. dry IC) at the recent contest.....very close....PLUS the 6 or so ounces of fuel....I reached out to Paul Winter....his electric Yatsenkos with battery weigh what empty IC versions of the commie planes.....Have fun!

[Frank Imbriaco]

 Composite aircraft can weigh less than traditional wood /painted finishes.

Can't say  I agree that building lighter aircraft is easier ; IC or electric.

[Brett Buck]

Yup Randy...the con is on.....
Checked weights (WITH Battery v. dry IC) at the recent contest.....very close....PLUS the 6 or so ounces of fuel....I reached out to Paul Winter....his electric Yatsenkos with battery weigh what empty IC versions of the commie planes.....Have fun!

  I know I will regret it, but what "con" are we talking about now?  There is virtually no one flying today at a competitive level that thinks Electric is at a disadvantage in any way, if anything, Electric has an advantage. Great, something works slightly better than the last thing, that's a wonderful thing. Most people are completely incapable of even evaluating it in either direction, because they can't get either one to work properly and optimally, so they are comparing the mistake they make with the mistakes someone else is making, not comparing a perfect working system to another.

     No one cares, it's not important, and it's not a "con".

      Brett

[peabody]

Brett
My examples demonstrate that electric has NO disadvantage as far as weight...more likely, IC engines are heavier at take off.
Just sayin

[Brett Buck]

Brett
My examples demonstrate that electric has NO disadvantage as far as weight...more likely, IC engines are heavier at take off.
Just sayin

  Suppose they are (in fact the current rules more-or-less guarantee that they take off with less margin over the pull test than electric - something everyone has long accepted and was designed into the rules)  - who cares? What difference does that make and why is it relevant?

     Brett

[peabody]

The thread began with a thought that an EMERGENCY safety proposal be made....
It morphed into proposing a rule change that would compensate for the "weight advantage IC engines had over electric"....
My statement of fact is that there is no real weight advantage for IC engines.....
Just sayin

[M Spencer]

Think over this ' PARITY ' is the word , I think .

With all the supposed ( reported ) advantages of Electric , I.C.E. need ' the Boost ' .

[Brett Buck]

The thread began with a thought that an EMERGENCY safety proposal be made....
It morphed into proposing a rule change that would compensate for the "weight advantage IC engines had over electric"....
My statement of fact is that there is no real weight advantage for IC engines.....
Just sayin

   There is certainly no emergency and if you dismiss that, the rest of it is a "don't care"/"in the noise"/irrelevant. Change the weight for electric, change the weight for IC, it doesn't make any consequential competitive or safety difference either way.

     And as always, you have immediately jumped to the conclusion that this is a "con", again spewing nonsensical accusations over a minor difference of opinion, and alluding to some sort of plot or conspiracy. One would have though you had learned your lesson in the 93-2005 time frame, but I guess not.

      Brett

[Randy Cuberly]

   There is certainly no emergency and if you dismiss that, the rest of it is a "don't care"/"in the noise"/irrelevant. Change the weight for electric, change the weight for IC, it doesn't make any consequential competitive or safety difference either way.

     And as always, you have immediately jumped to the conclusion that this is a "con", again spewing nonsensical accusations over a minor difference of opinion, and alluding to some sort of plot or conspiracy. One would have though you had learned your lesson in the 93-2005 time frame, but I guess not.

      Brett

I must take the blame (credit) for first mentioning the term "Con".  I did it however as a joke indicating that the reason for the requested change was simply to provide an advantage for the "Evil" Electric Guys!  it wasn't intended to be a serious challenge!

I believe this whole  fact that we have required line diameters and a pull test to be just more belt and suspenders "seudo" safety regulations that have no real foundation in fact or necessity!  Of course I really don't think Electric guys are "Evil"...well maybe one or two of them... and they know who they are!  But I have many friends and good nice people that have gone to the dark side and still remain NICE PEOPLE!  I certainly confess that I don't believe that the electric systems are better than the best IC systems but that they do have the technical advantage to become so!  I don't believe they are there yet however.  There is some small experimentation going on with IC engines that may level the playing field again.  Experimentation with air boxes and potential fuel injection systems while expensive could easily advance IC beyond the electrics and give more consistency...potentially of course!  Electrics are cheap and easy so they will have the high ground for a while.  It may simply happen that there is not enough remaining energy or desire in the old crowd that has an interest in Stunt to really worry about future advancement!   I would think if there are any real advances in either it will likely be from the Europeans.  They seem right now to have a bit more development interest! 

Right now even R/C Competition other than the stupid drones (and certainly the commercial usage for those has a determined place in the future) is highly questionable and on a big down turn!

Personally, I find disappointment in the fact that my period of greatest interest so far in stunt also comes at a time when my physical abilities due to age are also on a steep down slide!  RATS!  Nothing ever seems to come together...such is life!  Oh well I've hopefully got a few more years wiggleing the handle even if I don't ever actually win anything!

Randy Cuberly