stunthanger.com
Building Tips and technical articles. => 1/2 A building. => Topic started by: john vlna on November 16, 2014, 05:37:00 PM
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Back in the early 80's there was a FF rubber model of a Shinden published in , I think, Model aviation. I build a CL version and flew it with a Cox .049. Since then it has been through a couple of conversions, crashes and repairs, but still keeps on flying. I did a quick rehab for my club's 1/2A day this coming Saturday. Currently it is electric. I am using a Turnigy 2211-2300 motor, 2 or 3 cell LiPo, 12a esc, and 2.4Ghz throttle. With only 60 sq in wing area it only goes round and round, but with throttle touch and goes are possible.
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Neat! What's the wingspan?
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16 inches, if I ever made another one it would be larger. IIjust copied the FF plan
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This would be awesome scaled up to a .40 sized Stunter. VD~
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I think I would build a bigger 1/2A version first. In fact I have been thinking of just that this winter. The model would be based on a RC 24" span plan, mostly foam, and electric.
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It would be especially awesome if someone could make a canard stunter work. Tom Lay built, crashed and rebuilt and then crashed the design that was supposedly flown successfully at the Nats. Tom was a meticulous builder, expert flyer, Master Engine Guru and the thing wouldn't do a loop without disaster. It is worth a new thread to explore the problems and complexities of canard stunters. There have been several, but the most successful canard of all time dates from 1902,and it wasn't even designed to be stable in pitch because bicycles are inherently unstable.... LL~
I don't want to ding Burt Rutan, but his designs were NOT intended for stunt! His whole schtick was spin stall safety and efficiency. ( Which doesn't seem to help if you fly drunk in a new airplane like a famous singer was reputed to do. I hope he reincarnates on a sailboat, in Colorado or on a Country Road, I loved his music)
(If anyone has other information about that fatal crash, I will be delighted to retract my statement.) :'(
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I built an all sheet 1/2A canard that flew pretty well once, although I wouldn't call it a stunter, but it was quite maneuverable.
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I have built and flown the canard that Richard Sarpolous designed and published in Flying models. It will do the AMA pattern, but not like an Impact or Nobler. It is strange looking from inside the circle and takes some getting use to. AM working on a variant Ringmaster Canard that just needs fuel tank and flying. I think the biggest problem is over control on the trailing moving surfaces. Won't have them on the Ringmaster Canard.
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It would be especially awesome if someone could make a canard stunter work. Tom Lay built, crashed and rebuilt and then crashed the design that was supposedly flown successfully at the Nats. Tom was a meticulous builder, expert flyer, Master Engine Guru and the thing wouldn't do a loop without disaster.
This one I think.
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( Which doesn't seem to help if you fly drunk in a new airplane like a famous singer was reputed to do. I hope he reincarnates on a sailboat, in Colorado or on a Country Road, I loved his music)
(If anyone has other information about that fatal crash, I will be delighted to retract my statement.) :'(
Well, the NTSB does spend your tax money trying to figure out why each airplane crash happens, and how to keep it from happening again. There's no mention of any alcohol-related impairment, which would, I expect, have made it to the front pages:
http://www.ntsb.gov/news/1999/990126.htm (http://www.ntsb.gov/news/1999/990126.htm)
Scuttlebut among my pilot friends at the time is that the problem was exacerbated by the fact that the plane builder was tall, and John Denver was short, and that the fuel switchover valve placement worked quite well with long arms and the seat back, but not so much with the seat forward and short arms.
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Here are a couple of photos of my all sheet canard built a few years back. It was quite maneuverable for a flat sheet model, and made very quick turns compared to a standard configuration. Span was about 20 inches. Even with the forward sweep quite a bit of weight was needed on the fore-plane. This made the booms subject to breaking if it landed hard. The blue tape was a field repair of a broken hinge.
John
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It would be especially awesome if someone could make a canard stunter work. ...It is worth a new thread to explore the problems and complexities of canard stunters....
I've read several articles/papers showing that, except for very specific conditions, canards are just not as efficient as conventional, aft-tail configurations. They suffer from having the main (larger) wing operating at less than its maximum lift in order to have static and dynamic stability. Also, the canard wash encounters a good portion of the main wing's span, decreasing its lift more. Consequently, the canard plane loses more than it gains by eliminating down-force on a trailing tail. Hinged elevator or flap on the main wing of a canard aircraft must really place a heavier load on the front wing or compromise the lift of the larger "main" wing, depending on which way the surface deflects compared to the canard elevator. I'm thinking that the closer you get to the control you want in a canard design, the harder it is to control.
SK
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I think you are right on the control issue, at least from a CL Stunt view. Ever canard I ever built it was critical to get the cg correct for stunting, and even then a handful to fly. For just going round and round they seem to be ok, easy to set up.
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I flew my canard at VSC one year but was having engine problems. Bought an LA .40 and put on it with a Zinger 11-5 prop. It will do the pattern when conditions are right and the engine man sets the needle right. Yes it is very maneuverable. I now have two canards to fly when the weather breaks or I really get in the mood to fly.
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Quote: "Even with the forward sweep quite a bit of weight was needed on the fore-plane. This made the booms subject to breaking if it landed hard. The blue tape was a field repair of a broken hinge."
Forward sweep agrivates the tailheavy problem. You should have used sweepback, effectivly moving the engine forward compared to the center of the main wings area.
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Larry
Forward sweep moves the cg forward, the Engine is mid mounted thus the forward sweep helps center the engine on the cg and less fore plane weight is required . Back sweep would move the cg back requiring more weight.
John