What are you flying in Lim B

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Lee Liddle
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What are you flying in Lim B

Post by Lee Liddle »

We aren`t flying any Lim B down here right now, but I`d like to hear about what you guys are using. What works/what doesn`t.

Let us know what you are doing.
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boiler
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Post by boiler »

I'm flying a basic Piranha on a Battle Axe set of rails. I'm using a radio compartment instead of a wing riser. The Piranha wing with 2 inch airlons is just under 600 squares. The weight with full size servos is at 2# 3 oz so I will have to use a bigger battery or put a 1 ounce fishing sinker in the radio compartment. I'm using 25# foam because I can't find 40# locally. If I went to 40# foam, I wouldn't need the extra weight. 25fx with stock muffler and 15% nitro. 6ounce clunk tank.
Hat Trick
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Post by Hat Trick »

Basically the same as open :phence post and B-2 wing with the stock muffler and a required prop and a bunch of weight! Almost anything works as long as it meets the rules. Unfortunately my latest open planes won't meet the limited B rules because of to much wing area. But I don't get to fly open much so it shouldn't be to much of a gear drain! I built most of my wings light for SSC but armored up some for limited B so I don't have to add so much weight.

I did find that my FX's perform better than my webras in the limited configuration.
AIM
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Post by AIM »

I'm flying a fence post with Hattrick and Roid wings. I use all full size gear and even 6 and 8 channel receivers and getting right at 3.25 .lbs. I'm currently keeping my eyes open for a different fuse so I can hide all my gear in it but I haven't found it yet. I've been looking at trophy columns but many of them have internal webbing molded in them so stashing the tank inside wouldn't work.
Sean Rupp is building a boatload of JETT style of tanks That I wouldn't mind running but the 6 oz ones are about 2" longer than I can use with my current design.
About every engine you see out there works with the exception of the Magnum 25. All the others will spin up to 14,500 with not much problem but the mag 25 that I have seems to be stuck at about 13,200. The Mag 28 that I have on the other hand is a powerhouse. My FXs will also turn the 14500 with ease.
About anything a guy owns will work in LimB. Thats what I love about this class. It's very builder friendly.
Here is my current LimB plane design.
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Captain America
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Post by Captain America »

Lim b last year at the nat was brutal, more carnage than open... I desperatly want to go the route Mike is, I use a post and the b2 wing for ssc, lim and open. Unfortunatly I find myself adding a bunch of bi-di to the lim wings to up durability making them to heavy for the ssc and open wings. I need to settle in on a happy medium between weight and durability to make this a bit easier. I was planning on using up my old 1072 stuff in lim but I hear that is not going to work out for me.
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boiler
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Post by boiler »

Take 6 inches from each wing tip to fly them in Limited. I've been using 64 inch wings in open and limited. I also use the e203 airfoil which is thicker and stronger than many others. My planes seem to keep up speed wise pretty well.
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Post by Captain America »

1072s dont like to be shortened, they fly but get real snappy, Ill just finish them off in open
ZenManiac
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Post by ZenManiac »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Lee Liddle</i>
<br />We aren`t flying any Lim B down here right now, but I`d like to hear about what you guys are using. What works/what doesn`t.

Let us know what you are doing.
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">
What's up Lee? Are you going for the trifecta in the provisional classes next year? [xx(]
sgilkey
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Post by sgilkey »

It was my screw-up not to get the 64 inch span maximum eliminated (or at least voted on) for LimB, I missed the deadline for rules submissions. Last year to me clearly demonstrated that 72 inch span is no advantage for LimB. the current generation (i.e. AVENGER B2) 64 inch span planes clearly dominated, they roll faster and turn just as tight if not tighter. I still want to submit that proposal but the horse may have already left the barn. Using old beat up B ships was a nice draw for participation (and not dominance) in LimB, the span limit hurts that as I agree that trimming tips has, for me, led to snap-happy wings for some reason. Getting people to try combat with this class is much easier if the rules (ie span) are less restrictive, while not creating unfair advantages (which 72 inch span does not).

In the past, we flew our regular old AVENGERs and Chokers in LimB. As AAAAAAAAAron says, it's a great class in that you can throw the kitchen sink at it, we've flown old beater wings on coro fuselages, etc too. The Mag 25 is a bit of a weakling and Mike F found that the Webra on a muffler is not strong, but the FX, Mag 28XL, and Norvel seem to work great. I have a ton of old OS 28F heli engines that we first used when getting into B, that make wonderful LimB engines. About the same power as the 25FX and the added weight of the heli head is not a problem with the class weight min. I also have several SuperTigre 29s that work well for this class. With the rpm levels we're turning, fuel is not critical nor are plugs, and the plugs seem to last forever. The engines start and needle easily and are reliable as anvils.

I can't for the life of me make a decision on the prop. I THINK the MA performs slightly better, but then some days I fly the APC and it seems good too. Not much of a difference, in any regard. I tend to prefer the MA since it survives poor landings better.

I've not had a problem meeting the min weight since all the planes we've used so-far have been beaters retired from B use, with full armor. We have not purpose-built LimB ships until this winter. We've put together some Piranhas and AVENGER B2+s, both of which will probably be under 3.25# and will need to be ballasted for LimB- that way they can also be used for SSC. After flying all beaters in LimB, I was shocked at how well a virgin Piranha performed. Have not test flown our AVENGER B2+s yet but I saw enough of them fly last year that I know we will be very pleased, that wing is just superb.

We originally thought that 10x4/15.5k (initial performance limit) and 3.25# would limit performance and furballs/turning ability while still maintaining armor. We subsequently lowered to 14.5k but performance is still surprisingly high, the planes climb and turn very impressively and top speed is pretty good too. The performance was supposed to be SSC on steroids (mostly in launch and streamer-carrying ability, ie thrust) but it is definitely higher than SSC. Armor is not being maintained bacuase people are buildling dual-purpose planes and they want them to be light, and then ballast for LimB which does nothing for resisting battle damage. And the idea was to break up the furball and create more pursuit (which would theoretically reduce midairs, i.e. 2548) but the furball ability is definitely still there. So carnage can be high. NATS was the worst I've seen. We've done other LimB meets where carnage was low, and seen it all in between too. At our last club meet Brian flew every heat with the same AVENGER and had nothing but bumps and bruises. Eric flew an entire contest of LimB at Hillside with an old Hat Trick, which was still intact enough for him to enter in the next days C-Class contest (where it was mauled!). Some days are good and some not so good, we've seen the same thing in SSC though.

I find the class much more relaxing to fly than B, like 2548 is compared to 2610. I really enjoy it. It's still competition and can get tense, but not always to the max like B. The constant rush of B is still fun, but the more laid-back LimB is also a blast.
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Post by Hat Trick »

I like the 64" max span. Simpler to manufacture in foam sheets. Easier to transport. I do think that more wing area is always an advantage. Wing loading is a major factor in performance if everything else is equal.
Now I can use the same wing for Open B Lim B and SSC. It might not be ideal for each class in that I have to add a bunch of lead to Lim B planes where some more armor might be better but I like the simplicity! I did build a couple Lim B only wings this winter.
sgilkey
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Post by sgilkey »

The span limit and the wing area limit are not linked. You can't exceed the area limit whether you are 64 or 72 inch span, so the span should not matter.
Hat Trick
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Post by Hat Trick »

True! Cutting swath is a bit of an advantage though. I just like the shorter wings and having a standard size so there are no competitive advantages to be had at all. With no span limitation someone will come out with a 90 inch wing a couple inches wide.
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boiler
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Post by boiler »

I went to a 2610 meet and Bad Dog had a plane that looked like a glider. I think he had 2 servos on each wing half. The span was very long and the chord was short. I don't remember how well it worked out but I don't think it did all that well. As far as my preferences are concerned, I like the 64 inch span rule. I only fly 64 in open and 60 in SSC. I get good roll rates and the wings weigh less. There seems to be less destruction when you reduce the leverage on the wings. With the 600 square rule the wing would have to get a pretty short chord if the span went up. I know Dr. Evil's 72 inch (or more?) wings often wound up flapping because the glue couldn't hold the spars well enough against the stress.
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Post by Captain America »

I like the 64" stuff now that i have flown the b2s, I was just really hoping to use up my old 1072s in limited and move the new b2 stuff to open planes, this year i will have to fly the 1072s in open till Brian and I bust them all up then I can switch to my 64s. The roll rates and turns with the b2 are so much better It makes up for the shorter span. Going smaller is always against my better judgment but I was vry impressed with the new wing. If I did not have 5 1072s to use up I would have swiched totally this year. I guess thats the problem with building more than one wing at a time....
AIM
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Post by AIM »

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