What are you flying in Lim B

All Things Related to Limited B

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grasshpr
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Post by grasshpr »

Currently there is no Lim B flown in the Southeast so I won't be building just for it. I used my old beater fleet of aging Avengers last year at the Nats and will use the very same planes again this year for both classes.

As for carnage, maybe I'm just lucky, but that's the exact same 5 planes I started the '05 season with! After 2 full years of fairly active competition they will be used to start out this season also.

They barely come in under the 3.5 lb. max anyway after multiple repairs so wieght is not a factor. I don't mind swapping muffler / prop for the sake of a little more fun.

The last thing I'm interested in is gearing for yet another class. The guys down here are having a ball with open b and that includes the newbies of which there are quite a few. So far no arms race here and I certainly won't be the first or encourage any one else to introduce the kind of stuff I hear rumors about elswhere in the country.

IMHO it's not what class is popular in your area or what you personally prefer to fly that will return possitive results in the form of continuing activity and growth. I believe it is far more important to be in control of HOW I fly combat than WHAT CLASS of combat I'm flying.

What I mean is, speaking only for myself, simply that I don't need a limited class of what I already enjoy flying. I make it my business to enter every contest with the mindset that it doesn't matter in which place or with how many points I finish. I don't want to have some fantastic new design with an exotic motor to be able to outclass my friends.

I feel especially that way flying here at home, but also in the national and regional meets as well. It is more important to me to enjoy this part of my modelling hobby and if I go at it with a cutthroat win at all cost mentallity, the fun factor just went right out the window.

Please forgive the dialog but in answer to your question as to what I would fly in Lim B, honestly, I wouldn't be flying any Lim B if it wasn't kind of forced on me this year at the Nats. It makes me sick at heart that the few of us left flying scale are forced to fly ten rounds of each scale class in half a day that also includes Open B (two days in a row) just so they could ram Lim B down our (my) throat.

I'm sure to catch it for that comment, but no one seemed to listen to those of us responding that in no way did we want to fly 15 rounds in one day, and that no, we did not want to fly the whole ten round class in half a day (twice). They just posted a schedule that suited them and since they wanted Lim B, they did as they pleased.

Before any of you in the "They" category respond to ream me out, I read all your posts about the numbers, the carnage, the newbies, the open vs lim etc. etc. so no need to repeat. The majority rules and as you have made your case, I must accept and support the group descision. Well actually it may not be majority since we don't work that way, but the descision of our chosen representatives is what I mean.

The situation is simply that Lim B does not exist in my area and is not likely to untill the people taking the lead in directing contests take up the lim b banner. I remain open minded about it, but as of now am still content to fly Open B and have no interest in a limited version of what works quite well here so far.
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boiler
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Post by boiler »

Chris, you are welcome to your opinion and i agree with your philosophy of flying what your friends are flying. Different areas have different preferences at this time. The North and South seem to be divided on what form of B they want to fly. Limited B at the NATS will be flown if we have great weather and everything runs well. Even at that, we may get in less than 10 rounds. The first NATS that I attended had something like 20 heats of Open B and 15 heats of 2610 the first day and the same the second day. It made for a long day but you had to "get er done" because the time we were allotted was only 3 days. The weather was especially good last year compared to many of the previous years. Scale pilots may fly one or both classes and it seemed like we had time left over at the end of the first two days last year and then had a real push the second two days. As Rick and I scheduled the events we knew everyone would not be happy no matter what we came up with. Although you are one of a number that feel the same way, I hope you can forgive me for trying to get in as much combat as we can in the 4 days allotted.
AIM
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Post by AIM »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by grasshpr</i>
<br />

Before any of you in the "They" category respond to ream me out, I read all your posts about the numbers, the carnage, the newbies, the open vs lim etc. etc. so no need to repeat. The majority rules and as you have made your case, I must accept and support the group descision. Well actually it may not be majority since we don't work that way, but the descision of our chosen representatives is what I mean.

The situation is simply that Lim B does not exist in my area and is not likely to untill the people taking the lead in directing contests take up the lim b banner. I remain open minded about it, but as of now am still content to fly Open B and have no interest in a limited version of what works quite well here so far.
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I'll wave the LimB banner here for a bit. First off I'll say that I am a huge fan of LimB. I don't like the sluggishness of SSC and I don't like the foot to the floor Open. It's a snap to build for. The 3.25 min makes that easy. I build on a very (and I mean VERY) limited budget. I can use old heavy gear. $2 nicad packs, 8 chan recievers that nobody wants any more, big cheapy servos all around and about any engine I can snag off of ebay for 10 bucks, and still be right at the 3.25. What this translates into is that I can be JUST as competitive as ANYBODY else on the flightline no matter what they are using. A guy can use super light NimH packs, Little bitty receivers, micro servos, high dollar this and that whats he gotta do. (add weight) So we still end up the same. A guy can use a webra motor that he just snagged for $70 that'll turn 19500 and I can use my magnum that I got for $26 shipping and all and guess what. We both gotta 14500 limit so his motor isn't any better than mine.
Wether or not you fly LimB I really don't care but don't knock it. It's a very builder friendly, newbie friendly class that has it's place.
Oh and by the way. I do NOT want to do away with Open B.
I wonder if competitive quilting is strapped with the same problems.
Hat Trick
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Post by Hat Trick »

Funny thing Aeron is that THEY are flying limited B too! They just don't have rules in place to keep it that way!

Just got a Q40 Plyon engine for the Russia trip! Tom's already got a couple!

Duck and Cover!
AIM
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Post by AIM »

You should bring that pylon engine and a plane to Hillside to fly our first pylon event? I'm certain it'll be wild! Can't remenber the date right now though. June I think.
AIM
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Post by AIM »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by grasshpr</i>
<br />Currently there is no Lim B flown in the Southeast so I won't be building just for it.

They barely come in under the 3.5 lb. max anyway after multiple repairs so wieght is not a factor.

So far no arms race here and I certainly won't be the first or encourage any one else to introduce the kind of stuff I hear rumors about elswhere in the country.

I don't want to have some fantastic new design with an exotic motor to be able to outclass my friends.

I remain open minded about it, but as of now am still content to fly Open B and have no interest in a limited version of what works quite well here so far.

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Like mike says. You're already flying it other than a few rules.

Your comments about the "no arms race" "exotic motor etc" is exactly what LimB gaurds against.
Open B is getting faster and faster. (AS IT SHOULD BE ABLE TO DO). It's called OPEN. Just read the LSN debrief. If I read it correctly there was an electric plane there that was faster than hell. Hattrick and Stein are flying russian wings that scream. Roids planes have always been supercharged.
Open B is a great platform for speed freaks and adrenaline junkies and if I had the skills to be half competitive I would fly it more often
I have only been in combat a few years now and I have seen the "local boys" that I started flying with go from 50 mph spads to 100 mph exotics. They are having a ball innovating new ideas to raise the Open B bar. Next up I see electrics coming into play with some of the mind boggling rpm's that E motors can turn. All this in my opinion is where your group will go if you don't cap it. The last two words of your post sum it up.
Wingman
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Post by Wingman »

There may be a few pilots that are going faster in Open B; however, the majority are not. The motors, props and available airframes have actually remained unchanged for the past 4 years or so. Until the exotic engine/motor combinations are more affordable, I don't think we will see huge speed change in Open B.
grasshpr
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Post by grasshpr »

Aaron,

I have to 'fess up to being an alarmist and going on about pet peeves, but in the end it's all good (I hope). I was a little intimidated by the prospect of being out gunned and out run by new secret weapons, but after flying with both elecric and glow powered hot rods at LSN, it's not nearly so scary as all that.

Evan Wenger won with "conventional" Open B equipment if you will, and demonstrated that an outstanding pilot with "normall" speeds for Open B is able to compete effectively with the faster stuff.

Open B alows the enthusiast to go to extremes to push the allowable envelope, but for the average combat flier like me, that's not going to be easy to do. I have limited time and budget for my RC hobbying, of which combat is only one facet. As long as I can buy reasonably priced equipment that is plenty fast enough right out of the box, I don't feel the need to go beyond that.

Keeping with the Lim B discussion, I don't have a problem with it, just tend to balk at further fragmenting with another class to be juggled. What I mean is, from the standpoint of a CD and pilot, some division of time and resources is the inevitable out come of every new improvement in the form of a class with different ground rules.

Do you pick one or the other and go with it? Do you try to straddle the divide and use the same stuff for both? Can you afford to equip with enough stuff to do both effectively? As a CD which do you put up contests for and promote locally?

That's why I said for now I'll be content to fly Open B here. The guys in this area are having fun with open B and I'll do what I can to keep the interest level up by maintaining that enjoyment. If it becomes neccessary for us to try Lim B at some point, I'll cross that bridge when we get there.
Lee Liddle
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Post by Lee Liddle »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Evan Wenger won with "conventional" Open B equipment if you will, and demonstrated that an outstanding pilot with "normall" speeds for Open B is able to compete effectively with the faster stuff.
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I agree 100%. Speed alone will not win anything. And, speed that the pilot can not use effectively won`t help either. There is a reason that speeds in Open B have plateaued since the introduction of the moose can system. The reason is that the rot rods don`t win on any consistent basis. If they did, many would jump on the hyper-speed bandwagon.

Believe me, Grasshopper`s stuff is NOT Limited B equipment. I chased him and another plane of similar speed for over a minute in the last heat and didn`t get either one of them (full streamers). I probably had a little speed on them, but not much.

There is a wall out there near 90mph. To get past that you have to have a Fora or a Jett and a very clean airframe.

You hear a lot about 100+mph electrics, but those are tiny little pylon racer types or 36" flying wings that weigh about 1.5lbs.
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Post by AIM »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by grasshpr</i>
<br />Aaron,

Open B allows the enthusiast to go to extremes to push the allowable envelope, but for the average combat flier like me, that's not going to be easy to do. I have limited time and budget for my RC hobbying, of which combat is only one facet. As long as I can buy reasonably priced equipment that is plenty fast enough right out of the box, I don't feel the need to go beyond that.

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I'm in total agreement that Open allows for pushing the envelope and as I've said before (IT SHOULD) It's "open" and should be the most advanced, hair raising, wild ride out there. I support it 100%.
LimB just caps alot of that and allows for my limited budget to at least compete on a technological basis even though my physical and mental skills are lacking.[:D]
If you wanna go faster then you have to clean up your airframe or something like that. Exotic motor doesn't do a thing for you since 14500 is the limit.
If you wanna turn tighter you gotta work on throws and coupling. Wing loading is a mute point because it's all pretty much the same.

The biggest thing I think is gonna be a drawback to LimB is the research by some people dealing with what engine "unloads" better in the air. I've listened to conversations about X engine winds right out in the air especially when ran on a bladder. If that crap catches on then the 14500 limit on the ground will be useless. Another twist to that is the remote needle adjustment that Roid had on his plane at LSN. If it were up to me (which its not) I would outlaw that right off the bat. (for LimB, not Open)
I'm not saying that speed is the answer to all, and as Primetime showed at LSN skill is one of the biggest factors but flat out speed is a great defense.

More later (I'm tired)
sgilkey
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Post by sgilkey »

you're welcome to make a rules change proposal, Aaron! You (or anybody) can submit one. Personally, I don't think an in-flight adjustable needle is a problem, at least as far as I have pondered it. I HAVE seen examples of folks coming to tech in rpm-capped events such as LimB or SSC, with their engines running slobbery rich and below the peak, but you give 'em a good pinch and they cleaned up to WELL over the max (i'm not talkin' a few hundred r's here....). I would not pass them. This is an issue for the CD and tech inspectors, they need to be on the lookout when doing the rpm checks. Also, if a guy is really screaming in the air, he deserves a close look-see/audit check! I've never been too concerned about a couple hundred r's, it's always possible that you could be checked at, say, 14.4 and five minutes later, you land, your engine cools a bit, you recheck and it's 14.6- no big deal. I personally wouldn't zero a guy for that. But if the engine is really breaking out, i think it's a concern.
grasshpr
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Post by grasshpr »

Scott,
That's exactly right, and since you mention it I'll add my comment on the subject of rpm limit enforcement. In keeping with the Lim B discusion topic I only mean to point out the similarity between SSC and Lim B (or any limited class for example 2548) regarding an rpm limit.

As Scott points out I have also seen numerous examples of rich needle settings that when pinched up often go over limit. While not being solely the case with bladders, any fuel delivery system can produce the same result, they are always fairly rich to start with because of the nature of a balloon type bladder that has a higher preasure to start with and that preasure tapers off some during the run. Therefore you have to be rich to start the heat or run the risk of leaning out too much when preasure falls off. Also when your motor unloads in the air you want that extra fuel to produce more power (rpm).

So don't get me wrong, I'm not picking on the bladder guys, I use normally aspirated tanks for SSC and I always launch a few clicks rich just like they do.

Here's my point, and it's always been a bit of a sore spot with regard to SSC and therefore any other rpm limited class, Lim B for the sake of this discussion; If the rpm check is not done correctly, you don't have an rpm limited event.

I've gone on and on about the "pinch" method to get the actual peak rpm that an engine is set to produce and received a little flak for it, so here goes again.

If you see someone holding a tach to their engine and doing nothing whatsoever to bring that motor up to it's peak rpm for the reading, just go over to them and either offer to help or tell them to put the tach back in their pocket. The rpm of a running engine by itself is by no means the PEAK RPM.

You may want to check the free running rpm and set your needle by it because you know how you want to start your run, you know what rpm your bladder should be making to begin with, etc., and that's fine, but I'm talking about setting the barrel of your carburator to prevent breaking out. After setting needle as desired if the tach test is not performed by pinching it up to display the peak rpm, (which it will produce in the air and the pilot knows that), then once again I say you do not have an rpm limited event.

Furthermore if this test is not performed prior to each and every launch by the judge to prevent anyone breaking out from launching, you do not have an rpm limited event. The test when done right only takes a few seconds and if you are over you should not be allowed to launch. If you miss the launch window that's too bad, it's your responsibility to be set properly beforehand. If you're that close to break out and you don't set your barrel closed a little more to be sure of your limit, too bad, be ready to adjust quicky if you want to launch on time.

Some guys don't know how to properly pinch a motor up to peak to begin with, so those who do, might offer to help when they see others taching without pinching. Scott could no doubt describe it better for us as his pylon experience probably includes lots of pinching.
I learned the technique from my pylon friends down here and I use it to set a good needle on all my rc planes.

Very simply, you must pinch the fuel line feeding the carburator with enough force to completely shut off fuel flow for a split second and let go immediately. The engine revs up to its peak and you get that reading on your tach. The test should be repeated several times in rapid succession to get a good average of readings, since it tends to vary slightly with each pinch. If you pinch and nothing happens or it starves out and wants to die, it's set so lean it won't peak up any more or you may not be pinching hard enough to do anything.

An engine set so lean it won't pinch up, in my experience, will quit just about as soon as you launch it. It's too lean to stay running, especially under heavy loads like we put on them in combat.

Bottom line: if you don't enforce the rpm limit, why pretend to have one?

The LSN, as far as I was able to see, was run with an effort to enforce that limit. It was not difficult to do and I should hope to see other contests, especially the big ones, make the same effort to do so.

Lim B is a slightly different animal and may be easier to police the 14.5k limit on a .25 than it is the 17.5 on a .15. I still offer the same input however that unless you (contest directors and pilots) are willing to enforce an rpm limit on another limited class, then you don't have an rpm limited event. nuf said
Lee Liddle
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Post by Lee Liddle »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Very simply, you must pinch the fuel line feeding the carburetor with enough force to completely shut off fuel flow for a split second and let go immediately. The engine revs up to its peak and you get that reading on your tach. The test should be repeated several times in rapid succession to get a good average of readings, since it tends to vary slightly with each pinch. If you pinch and nothing happens or it starves out and wants to die, it's set so lean it won't peak up any more or you may not be pinching hard enough to do anything<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">

That`s a pretty good description Chris.

I too have seen quite a few misinformed competitors over the years who think that just opening up the needle to slow down the rpm is all that you have to do.

Taching before every heat is best, but only if it is done correctly, and enforced equally down the line.

There is the option in the rules to tach before the first round, and then do spot checks throughout the contest. That is the way we ran the LSN and overall I think that it was successful. Next year, I think that we will ad at least one more "tach everyone" round near the halfway point.

I also made it a strong point in the pilot`s meeting, that basically "if you are the fastest plane in your heat, you better be ready to be checked after the heat is over". I think that went a long way toward making sure that guys checked their own stuff. Nobody wants a goose egg.

I also (as a pilot) asked for an rpm check on a specific plane after a heat. I didn`t make it a secret, and went over to watch the check. The pilot passed, and everything was good. I`ve been checked post heat several times, and am not offended if it happens.

My point is, it`s up to everyone..... CD, judges, flying pilots and watching pilots, to help police a well run rpm limit event. RPM limits in some events are good and are here to stay, so we all need to learn how to make them work well.
Captain America
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Post by Captain America »

Chris,

I want to add to your "pinch test" thoughts where bladders are concerned. I run Jett style bubbleless no bladders. I have been studying the bladder system in ssc to understand the advantage of it. I dont claim to have any answers but I did observe something worth noting for tech inspection.

At nats last year I watched a lot of bladder setups. I noticed that most set the rpm with the needle and most seem to be terrible rich but a "Momentary pinch" was not enough to lean them out. A bladder has enough pressure the keep the engine rich past the normal pinch. The one in particular I watched carefully would hit the 17500 and survive the test, but what I noticed was the pilot pinching and holding the test for a couple seconds, it would finally lean up and flash 21k peak! As a rookie pilot and to tech I never even thought about that or had the desire to confront anybody about it.

The mysterious unloading, all the engine mods and pinch test stuff finally fell in to place in my mind. Im not by any stretch saying that everybody who runs a bladder is trying to pull something, just that I believe the pinch test rule needs to be properly implemented as it seems to be a little different in nature on bladders than regular tanks.

Most of the guys we fly with dont run bladders so I have not had the ability to test this observation any farther.

As for your dislike of the class in general (Back to Lim B) I would rather fly open any day but since guys do want to fly it around here and at least last year I could fly the class by changing props, muffler and adding a weight... Ill do it and i won't complain
too much about it except where Aaron is around to hear about these slow heavy pigs...[;)]
Lee Liddle
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Post by Lee Liddle »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">At nats last year I watched a lot of bladder setups. I noticed that most set the rpm with the needle and most seem to be terrible rich but a "Momentary pinch" was not enough to lean them out. A bladder has enough pressure the keep the engine rich past the normal pinch. The one in particular I watched carefully would hit the 17500 and survive the test, but what I noticed was the pilot pinching and holding the test for a couple seconds, it would finally lean up and flash 21k peak! As a rookie pilot and to tech I never even thought about that or had the desire to confront anybody about it.<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">


If a bladder system is set too rich (meaning not ready to launch or it will be too rich in the air) it does need more than a quick pinch to get it up to peak. If a bladder system is set ready to run, it should only require a quick pinch or two to get it up to peak. However, this is also true with any fuel system. I`ve tested conventional tanks which had to be pinched for extended time or several quick pinches in a row to get them to peak.

Any system should be pinched with multiple quick pinches until the rpm stops increasing. Only then do you have a proper pinch test.
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