stunthanger.com
General control line discussion => Open Forum => Topic started by: Charles Carter on December 31, 2016, 07:35:10 PM
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https://youtu.be/aVPL4ujslbw
I am excited about this new plane. This is my first model using a Rabe rudder. I installed adjustable Tom Morris horns and used Dave Brown arrow shaft rod. A Bill Byles adjuster near the flap horn and Tom Morris slider adjustable elevator horn at the rear. Rounded the leading edge of wing. Hallowed the inboard wing tip and reduced it's weight by .5 ounces. Replace the canopy with a Hawker Hunter canopy from Eric Rule and installed a bigger rudder . Installed longer landing gear to clear a 14" prop. Power is a Stalker 81RE and home made 7.28oz metal clunk tank.
Charles Carter
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Wow, looks good!
MM
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Thank you! Happy New Year.
Charles Carter
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Looks great Charles!
Sent from my SAMSUNG-SM-G891A using Tapatalk
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Thank you James.
I did get a chance to fly it this week and it shows promise. Judged from others it's wing flew level both upright and inverted. I plan on more trim flights next week. But so far so good.
Charles
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It looks terrific, Charles. I like whatever that is over the venturi, easy to get a finger over it to choke.
When you feel like you're getting comfortable with it, get us some action video. Better do it before you get too comfortable though Lol... Juuust kidding. I bet it feels like hanging onto a horse compared to the planes I fly.
Rusty
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Hi Rusty,
Thanks Rusty. It flys comfortable believe it or not. I have a TF Score with ST 51 and it pulls harder. That Stalker seem to run a lower rpm with a lot of torque.
Charles
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Hi Rusty,
Thanks Rusty. It flys comfortable believe it or not. I have a TF Score with ST 51 and it pulls harder. That Stalker seem to run a lower rpm with a lot of torque.
Charles
I wish we could figure out how to show photos and videos in our live chat sessions. I'll try to get my little XP Acer eePC to work for the hangouts, then I can take the chats to the shop like the rest of you guys. I finally got some momentum going with my new Twister wing.
My Magnum pulled so hard it walked me like a dog in a breeze. I used to wheel-hop it sometimes at turn 4 of the hourglass. It was 72 oz. and I weigh 125 pounds. Wayne and Bob witnessed its final wheel hop and helped me put it in a grocery bag. ::)
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OUCH!!
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I have a 72 ounce Impact powered by a little OS 40VF, it pulls really hard at times, I think my right arm is longer than my left! ~^
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Looks good you did a nice job on it. Good flying this year.
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Thanks John and Terry.
Charles Carter
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Enjoy it Charles. Like the add ons that you did to personize it.
Fly on:::::::
Shug
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Thanks Shug,
I hope to fly it tomorrow Jan 2nd and I will try to get some video of.
Charles Carter
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Hey Charles it should serve you well. Keep us posted.
Like the canopy!👍🏼
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Nice!.... Hope you will post some flying videos
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Hi Charles, it looks like all the Windy videos I let you borrow paid off.
Nice job. W.W.
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Thanks Rootbeard and Steve.
Warren I really appreciate your generosity with those Windy videos. Your Strega kit was really nice. I have a video of one of your flights of your Strega at Whittier Narrows and it was a good flier in your very capable hands.
I will post some videos when I can.
Charles Carter
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Nice job and best of luck flying it. I'm working on an ARC Strega with ST 60. Monokoted wings and flying surfaces,tissue and dope fuselage.
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HI Skip,
If you have any questions for me fire away? I didn't mentioned it earlier but I reinforced the wood to wood joint of the wing saddle with a type of biscuit joinery. You should do well on the finish of monokote wing and painted fuse. If I wasn't in a hurry I would have preferred to paint the fuse.
Charles Carter
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Nicely done sir! I was hoping to be up there with you today to check it out, but the rain is keeping me away. Have fun!
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Hi Keith,
Thanks Keith. The rain really wasn't a factor in Escondido to bad you didn't make the drive. We had all the usual suspects show up. Dave Sabon, Bob Brooks ,Dan Sick, Preston, Karl, and myself.
Charles Carter
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Charles the one I'm working on has modifications as well. I removed the stock canopy which is directly over the flap horn and elevator attachment point.I did this so I could go in there to make trim adjustments. I have a removable hatch on the top of the fuse to access the area. I'm going to use a SiG WWII type canopy moved forward of the access hatch. I too will enlarge the rudder and use the Rabe set up. When I covered the wing I left about 3/8" uncovered on each side of the fuse /wing junction.I make some nice fillets from micro balloons and resin to the fillet area.
I'm going to cover the flaps with 3/4oz glass cloth to stiffen them a bit and paint to match the Monokote wing covering.
I have weighed all of the components and a 64 -65 oz model is a real possibility. It should fly fine with a ST 60 at that weight. Gotta go I've got some Monokoting to do tonight....PhillySkip
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Hi Skip,
I am interested about your hatch being on the top. Is there an advantage of it being on top instead of the side of fuse? How did you setup your Rabe rudder? Here is picture of my Rabe rudder setup.(http://) You can see the two hatches I have on the side of my fuse. The hatch behind the flap is kinda hard to see, the hatch below the elevator is more visible.
Charles Carter
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The plane is not finished at present,but I will post pics when she's done. I thought the cutting into the side of the fuse in the flap horn area would weaken the the plane,so I placed it on top. I actually created a lot of extra work for myself because I had to carefully remove the ARC's factory installed canopy, cut out the top of the fuse,make a contoured hatch ,hollow it out and figure out how to secure it. This morning I fiberglassed the fuse top. I'll take a pic of that and try to post it up.Regarding the rudder,the final set up will look just like yours.
At present I'm also finishing up a restoration of an Ares built by "someone" who did a great job on it originally.I think the plane was built back in the 1960s. She was covered in silk and dope. Took a while to get all of that off and sanded for refinishing. I cut into it and modernized the control system.Smooth as glass now!
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Hi Skip, I look forward to see the pics. Is this picture I took at Brodak 2016, is this you?
Charles Carter(http://)
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Looks nice Charles. Hopefully I can try to join you guys in the hangout sessions again soon...been crazy busy with work and things here.
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Hi Jared,
Thanks for your suggestions regarding the Strega ARF from our conversations. I hope to see you on the hangouts when you can join us.
Charles Carter
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Charles that's me alright,but please don't share that with too many folks as I'm in the witness protection program under the alias " Mr. Showtime".....hehe
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Yo I know you! It just came back to me. Aren't you the cat who flew out to the meet with another Cali guy who flew in Expert? If you're that guy then you're a firsthand witness to the demise of my teal colored 59 Ares. Are you that guy?.....Skip
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(http://)
Great memory Skip. Your are right I am the guy. This is me flying at 2016 Brodak's with a borrowed TF Tutor 1. The first time I flew the plane was in a competition and no practice flight or anything. After John Wright release the plane It was the first time I didn't know what to expect. Since then we refer to the plane as "Cold Turkey". Photo was taken by Will Hubin.
Charles Carter
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It's a small world right? I'll try to get some pics up today of stuff I'm working on .Regarding the Strega,I'm fiberglassing the fuse with ultra light glass cloth (did some last night) and I'll fill the weave with some filler coat that Joe Adamusko taught me how to mix up. I cut in a hatch about 1''x 1'' on the fuse left side to get into the elevator horn and push rod. All of my planes from here on will have adjustable "everything". This is so important to get a ship really trimmed out.
Did you get to fly your Strega? Stay in touch!
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I see you did fly the Strega,I missed that post. Here are some pics of the stuff I was talking about on the Strega and that Ares I'm working on...
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That will work for a hatch. I love the pilot screaming in the Ares. The pilot is probably reacting to and outside square.
Charles Carter
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He was told by other pilots in the "pilot drawer" of my shop about the Brodak Ares lawn dart outside square and he's screaming "Get me out of here,get me out of here!"
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Looks great Charles!
Which fuel are you running?
Are you going to the Az contest at the end of the month??
Mike
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Hi Mike,
Thanks for your compliment regard my Strega. I have mostly done a few trim flights using Cool Power 5% nitro and I added a little oil to bring up to 20% all synthetic oil. Unfortunately it is looking unlikely at this time to make the Southwest Control line Stunt Championships this January.
Charles Carter
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Charles ,what is the finished weight of your Strega? I bet that .81 really pulls it around.
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Hi Mike,
Thanks for your compliment regard my Strega. I have mostly done a few trim flights using Cool Power 5% nitro and I added a little oil to bring up to 20% all synthetic oil. Unfortunately it is looking unlikely at this time to make the Southwest Control line Stunt Championships this January.
Charles Carter
What better time than the Champs to put finishing trim flights on the plane? Plane looks great by the way.
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Hi Skip and John e.,
The last time I weight it at 74 oz. I have ordered a carbon fibre spinner which I hope will drop it down to 73 oz. It still has 1.5 oz wing tip weight in it at the moment. As I stated earlier I am still trimming it so it probably will drop some of the wing tip weight. I also am going to try some beechwood props to lighten it up further. Regarding the pull of the Stalker 81 RE it is a comfortable pull. The torque is absolutely amazing. I suspect because of it is a lower rpm it is also surprisingly quiet. Thanks you guys for the compliments I really appreciate it. Sometimes when I look at my Strega's color scheme it reminds me of "McDonald's". I try not to look at it with an empty stomach. LL~
Charles Carter
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Hi Skip and John e.,
The last time I weight it at 74 oz. I have ordered a carbon fibre spinner which I hope will drop it down to 73 oz. It still has 1.5 oz wing tip weight in it at the moment. As I stated earlier I am still trimming it so it probably will drop some of the wing tip weight. I also am going to try some beechwood props to lighten it up further. Regarding the pull of the Stalker 81 RE it is a comfortable pull. The torque is absolutely amazing. I suspect because of it is a lower rpm it is also surprisingly quiet. Thanks you guys for the compliments I really appreciate it. Sometimes when I look at my Strega's color scheme it reminds me of "McDonald's". I try not to look at it with an empty stomach. LL~
Looks pretty good. I wouldn't worry too much about the tip weight, these airplanes frequently end up with 2.5-3 ounces of tipweight. You just have to put in what you need, regardless of the overall weight. It's a *very large* airplane by modern standards and mid-70's is probably fine - as long as you rounded off the LE of the wing.
Same with the spinner and propellor weight. Unless using lighter parts lets you remove weight from the tail as well, you can't really get ahead by using lighter components. The CG has some tolerance to it, but you might have to add weight back in to get it to balance.
Just trim it however it needs to be trimmed, and then see how it flies. In the vein of trimming, I strongly encourage you to put the rudder on straight ahead and in a fixed position until you get everything else perfect. Then and only then should you make it movable and then adjust *only* the rudder to get rid of the small residual motion you can't otherwise trim out. Don't worry, at 75ish ounces and an .81, lack of line tension will not be a a problem!
Brett
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Thanks Charles for the info. I weighed my Strega with ALL components, all flying surfaces covered with Monokote, Fuse and "to be" painted parts covered with 6/10 per oz glass cloth. Mine weighs 61.25 oz right now. Finished weight should be 64 -65oz. She should fly fine with my ST60.....PhillySkip
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Hi Brett,
Thanks for compliment on my new Strega. I have been told repeatedly by expert pilots that you know what your talking about when it comes stunt models. So I will head your encouragement regarding the Rabe rudder. Besides it will be interesting to know what the effect of the Rabe rudder is engaged and not engaged. Thanks for your comment regarding tip weight. Regarding the LE of the wing that was one of the first things I did was to round it as much as a I could.
Regarding the balance of my Strega before I flew it for the first time I balanced it nose heavy just to be on the safe side. Since then little by little I have removed all of the nose weight and went from a heavy 14" APC prop to now rev-up 14" and to my surprize it didn't become sensitive or anything like that. When the engine shuts off the plane glides better then any I flown. It is a pleasure to land without any hint of stalling when I make adjustments. I am interested in possibly replacing the elevators with lighter c-grain wood to maybe lighten up the tail as well in addition to what I had mentioned earlier in the thread.
I am still feeling this plane out and I am very interested in learning it limits as far trimming it. The rain of lately has slowed me down from flying it but when the weather turns around I be out there.
Charles Carter
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Thanks for your comment regarding tip weight. Regarding the LE of the wing that was one of the first things I did was to round it as much as a I could.
Regarding the balance of my Strega before I flew it for the first time I balanced it nose heavy just to be on the safe side. Since then little by little I have removed all of the nose weight and went from a heavy 14" APC prop to now rev-up 14" and to my surprize it didn't become sensitive or anything like that. When the engine shuts off the plane glides better then any I flown. It is a pleasure to land without any hint of stalling when I make adjustments. I am interested in possibly replacing the elevators with lighter c-grain wood to maybe lighten up the tail as well in addition to what I had mentioned earlier in the thread.
I am still feeling this plane out and I am very interested in learning it limits as far trimming it. The rain of lately has slowed me down from flying it but when the weather turns around I be out there.
I think you will find the airplane very insensitive to the CG position compared to the airplanes you may have had before. Not only is it just plain heavy, it also has abundant tail volume which permits you to run it as designed with a far forward CG and still be able to turn (as long as your forearm is strong enough), or run the CG aft without going unstable as quickly. It's a very substantial improvement on the old classic models and most of the trainers like the Twister, etc. At the end, Windy was trimming his similar airplanes with an extreme aft CG to the point it was neutrally stable with very little control force required (according to those who flew them whose evaluation I would trust). With the sort of funky airfoil, you have to go a little easy on the aft CG because an aft CG also means less flap deflection, and at some point it will start stalling even with the rounded-off LE.
It was designed around the idea that you wanted a far-forward CG for stability, and then, to get it to turn, you had to generate a huge amount of elevator authority. That leads to requiring a huge amount of line tension, because otherwise, you couldn't move the controls far enough. You can deviate quite a bit from that safely, but I would defer to the guys who flew these sorts of models all the time back east, and err on the side of a forward CG. This is the area that other more modern designs have an edge (as briefly discussed in the other thread). You're never going to be able to turn it into an Impact, and you will always have to have a lot of line tension and control loads.
Brett
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Could one generate a huge amount of elevator authority by making the elevator about 3/8" larger around the perimeter? I was watching Windy's Strega ARF trim video and he recommended increasing the flap and elevator size by 3/8" around the perimeter for a killer Strega setup.
Charles
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Could one generate a huge amount of elevator authority by making the elevator about 3/8" larger around the perimeter? I was watching Windy's Strega ARF trim video and he recommended increasing the flap and elevator size by 3/8" around the perimeter for a killer Strega setup.
Oh, good Lord! That's what I would call, charitably, bad advice. Same thinking that makes the Cardinal impossible to fly well.
For goodness sake, don't make the flap any larger! It's already far too large, thats a big part of the problem. Make the flap larger, and it makes it even more difficult to move the controls, which leads you to even more trim compromises, which leads you to even more noseweight and even more elevator deflection - which, since it is larger, too, makes it harder to move the controls. That turns it even more into the "anti-Impact". If anything, if you got the LE rounded off enough, you would want to reduce the flap area.
I would suggest just trimming it as is, until you find some shortcoming (or your forearm proves inadequate, particular in the wind), then address that shortcoming as it is.
Brett
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It probably doesn't' make a difference but just to be fair to Windy he made this suggestion in regard to using a 90 size engine in Strega and making it a true 90 ship from a 60 size ship. I just want to be accurate in regard to what Windy said. I understand about the Flap to leave that alone as far as it current size. Just for clarity if the elevator was made 3/8" larger in its perimeter wouldn't that increase the elevator authority?
Charles
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It probably doesn't' make a difference but just to be fair to Windy he made this suggestion in regard to using a 90 size engine in Strega and making it a true 90 ship from a 60 size ship. I just want to be accurate in regard to what Windy said. I understand about the Flap to leave that alone as far as it current size. Just for clarity if the elevator was made 3/8" larger in its perimeter wouldn't that increase the elevator authority?
Charles
Yes, but again, that increases the control loads. Look at an Impact, or my airplane - the elevator is much smaller than the stabilizer. That's because the effectiveness of the control goes down only slowly with the "split" but the hinge moment goes down drastically. In fact, the one page of Abbot and Von Deonhoff that Big Jim and/or Windy fixated on (figure 115) shows that the lift coefficient goes up until you to about 40% "flap". That was a horrific misinterpretation for the wing since you couldn't possibly deflect a 40% flap using the existing line tension. But it works OK for the stab, and guess what, the Impact stab is 60/40. But the slope is very low around there, and 65/35 gives you almost as much lift, but much less hinge moment, which is how I did it for the Infinity.
If you make the elevator bigger, you get a little more lift at the same deflection, but much more hinge moment, so you probably can't make it deflect as far, so you will likely lose out. To get ahead, you would have to figure out some way to get more control torque, with either a larger bellcrank or more line tension, or both. If you try the "more line tension" approach, that means you have to compromise the trim in other ways. And, start taking whatever Barry Bonds was on, because the kind of muscle required to horse it around a competitive pattern is in the realm of the Incredible Hulk.
You would probably do better to increase the size of the stabilizer instead of the elevator, but I don't suggest any changes to the existing airplane. If it seems like something you want to pursue, then you can address it next time.
What you need to convert the Strega into a "90-sized" design is not more flap or elevator area, but 85-90' lines - which is illegal. This was the big problem with all of these gigantic bombs, you can get it to fly OK but the available space is too small for it. Even then, you can't actually use the full capability of a 90, and if you wanted to, you would run into the other problem that Windy discovered (after having other people, myself included, trying to explain it for years before) - that you can't control it. With no pipe to act as a regulator, you are trying to run a 90 at 10% of its capability. But if you get off a bit and end up with 11%, it's way too fast, and 9%, it's way too slow. Windy tried this at the NATs one year, found exactly that problem, and had to switch, in the middle of the week, to a 76 - where you need maybe 15-20%, and a slight variation wasn't a disaster. That's the airplane that later flamed out inverted and flew into the light socket pole.
David and others can use a 75 in his tiny airplane (small even for an ST46) only because he has a pipe to regulate it. The original airplane that the Strega is based on was the Patternmaster, which was intended to be big enough to cover the tolerance/variations that you get from an ST60 - not a 90 with 50% more displacement. It's (in my opinion) already too large for the 70' line length limit.
We shall see, of course, but I think you are likely to run into difficulties with power control and control loads even as it is. I am not sure (nor is it clear to me that anyone is sure) whether the 81 is detuned enough to be controllable in this situation. Making the flaps and elevators larger would just compound the problem with the control loads, and you might be looking to shave the flaps, for sure, just to be able to get it to maneuver in the cramped space available.
At this point, just get it going as it is and see what you wind up with.
Brett
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Hey Brett,
Thanks for taking the time to hash this out again. I assume this has already been discuss. Myself and others who read this thread are better for it. Regarding Double Star being detuned enough to be controllable do the pattern in a cramped air space time will tell. We usually see each other a couple times in the course of the year, so hopefully we will meet later this year.
Charles C
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Hey Brett,
Thanks for taking the time to hash this out again. I assume this has already been discuss. Myself and others who read this thread are better for it. Regarding Double Star being detuned enough to be controllable do the pattern in a cramped air space time will tell. We usually see each other a couple times in the course of the year, so hopefully we will meet later this year.
Bring it down to the Southwest Regionals at the end of the month, Dave and I are going and we would be glad to help! You'll see if the LE is rounded off enough or not, since its also 2200'.
Brett
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Bring it down to the Southwest Regionals at the end of the month, Dave and I are going and we would be glad to help! You'll see if the LE is rounded off enough or not, since its also 2200'.
Brett
Absolutely....Southwest Regionals, Tucson Arizona, Saturday and Sunday, Jan 28 and 29. There is a flier available elsewhere on this Forum.
Randy Cuberly
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I'm really enjoying the discussions on the Strega. Thanks to everyone who has joined in. Attached is a pic of my Strega getting the incidences checked. Good thing I did... the stab was off by 2 degrees negative. If my plane doesn't fly as it should it won't be because the alignments are off....LOL.
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I really would like to go the SouthWest Regionals later this month. But unfortunately the finances just will not allow it. I am familiar with most of the pilots in AZ and I would love to go there sometime.
Charles C.
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Charles.....I did make new flaps for my Strega. Same size just a bit thicker.
Shug
From a PM I got....who flys a Strega:
First let me tell you about 2 new tricks that are very very important. The Strega airfoil ain't the best so you need to do 3 things to help the wing do its job:
The 1st one you have already done, rounding the L.E. as much as possible.
The 2nd most important thing is to change the flaps. The flaps that comes with the kit are too thin and weak, twists very easily and that is bad. So If you want the Strega to fly well, discard these flaps and make new ones in the same size, but make them strong using the thickest sheet of balsa that will fit with the wing. Do not taper the flap and also do not round the T.E. Very very important not to round the Trailing edge, leave it square! The square T.E. has proven to me to work much better, if you want to know why and the Theory behind this I will be glad to explain it to you. Most of the Top Flyers in the World use square T.E. for good reasons. When I built my Strega I did these things plus I reinforce the flap with fiber glass and epoxy. This is the easiest way to make a strong flap, but not the best. There are better ways to make flaps, like using a torque tube of aluminum or a specialized carbon fiber tube with the fibers rolled at 45o. The important thing is making the flaps very strong so they will not twist easily.
https://youtu.be/pYkywY3eYrw
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Today I enlarged the fin and rudder (built up,not solid sheet) and added a dorsal fin also built up to rear turtle deck. I also fiberglassed my flaps and will put a couple of coats of resin to stiffen them up. Looks like my Strega is gaining weight and will be beyond the 64 oz I was hoping for....oh well???
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Shug,
I like the idea of strengthening the flaps. I will make some new flaps soon. Thanks!
Skip,
Keep up the good work. I especially like the way a dorsal fin looks on the Strega.
Charles C
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Surely Elevator ( and Flap ) Aerodynamic Balance ' ears ' would considerably reduce control ' effort Vs Movement !?
(http://spitfiresite.com/wp-content/uploads/2011/07/FSC06686.jpg)
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Surely Elevator ( and Flap ) Aerodynamic Balance ' ears ' would considerably reduce control ' effort Vs Movement !?
Certainly, but you would want to do it to the flaps. The elevator is a minor contributor. . You could use "spades" without too much disruption, but I like Howard's solution better.
Control loads are a big deal. It's pretty hard to do the tiny precise motion control motions required, while you are also white-knuckling it just to get the controls to move at all and holding against 15 lbs of line tension. That's one reason airplanes are tending to get smaller over time. You made them big because you had to, to control the speed with larger engines. As we got better control over the engines, the airplanes got smaller for a given amount of power.
Brett
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Hi Brett,
Please explain "spades"? What is Howard's solution? ???
Charles C
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I think a Strega that looked like a Mustang would be neat. A fin, rudder and dorsal that is P-51 will be nice.
Chris...
Today I enlarged the fin and rudder (built up,not solid sheet) and added a dorsal fin also built up to rear turtle deck. I also fiberglassed my flaps and will put a couple of coats of resin to stiffen them up. Looks like my Strega is gaining weight and will be beyond the 64 oz I was hoping for....oh well???
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Hi Brett,
Please explain "spades"? What is Howard's solution? ???
Charles C
Spades are aerodynamic counterbalances (that look kind of like shovels, which hoity-toity types and Anglophiles call spades). The picture below shows them. They are used on full-scale aeorbatics airplanes ailerons to reduce the control loads. They work exactly like the Hurricane elevator counterbalances in the previous picture. They have to be on a stalk to permit the aileron to move. You could do the same thing on the flaps to reduce the "stability" of the flap, and thus reduce the control loads. Basically they move the CP of the surface closer to the hinge line. It's just like a mass counter-balance, except it is aerodynamic.
Howard's airplanes have, of late, had a different way of doing the same thing, servo-tabs. I am sure that someone will post a photo soon, but effectively they are small moving trim tabs, connected to the fixed surface in such a way that if you try to move the flap "down", the tab moves "up" and applies a torque that tends to reduce the hinge moment.
The general topic of reduced control forces is discussed here, and much of it is applicable to our problem:
https://history.nasa.gov/monograph12/ch6.htm
Brett
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Spades are aerodynamic counterbalances (that look kind of like shovels, which hoity-toity types and Anglophiles call spades). The picture below shows them. They are used on full-scale aeorbatics airplanes ailerons to reduce the control loads. They work exactly like the Hurricane elevator counterbalances in the previous picture. They have to be on a stalk to permit the aileron to move. You could do the same thing on the flaps to reduce the "stability" of the flap, and thus reduce the control loads. Basically they move the CP of the surface closer to the hinge line. It's just like a mass counter-balance, except it is aerodynamic.
Howard's airplanes have, of late, had a different way of doing the same thing, servo-tabs. I am sure that someone will post a photo soon, but effectively they are small moving trim tabs, connected to the fixed surface in such a way that if you try to move the flap "down", the tab moves "up" and applies a torque that tends to reduce the hinge moment.
The general topic of reduced control forces is discussed here, and much of it is applicable to our problem:
https://history.nasa.gov/monograph12/ch6.htm
Brett
Brett,
I found this short video demo of "spades" Now I understand what you was talking about. Has "spades" been tried or used on a control line stunt ship?
Charles C
https://youtu.be/gQTbH0aTUek
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shovels, which hoity-toity types and Anglophiles call spades)
Not So ! . :o
Shovel.
(https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcQ5uXUqHunKHVsQ6v7Yc590U2g9trIdbW3Er4Vm-t-OB7FUys07sA)
(https://www.qy1.de/img/spaten303610.jpg)
Spade.
S?P S?P VD~
(http://www.everydaynodaysoff.com/wp-content/uploads/2010/11/Tactical-Pitchfork.jpg)
Told this is a ' Tactical Pitchfork ' Used to round up Downed german Airman , in that Battle of Britain . The illumination would be usefull at night . will have to fit it to mine ! ;D Intruders get the point .
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(Clip)
Here is picture of my Rabe rudder setup.(http://)
(Clip)
Charles Carter
Hi Charles,
I do not think we have met and I am getting in to this discussion a bit late. I can recommend to pay serious attention to what Brett has to offer.
This about your movable rudder. If you already have experience with the Rabe Rudder and know how to trim for what you want from your model, then disregard the following.
Now, with regard to the photos you showed of your Rabe Rudder. It appears that the elevators are at neutral in that photo. It could be just the camera angle, but the rudder offset with that neutral elevator position appears to be large. I think for initial trimming, you might want to use no more right rudder offset at neutral elevator than you would use if you had a fixed rudder. Then, if more right rudder seems to be needed for your outside maneuvers, go for it. But with a Rabe rudder and when it is properly trimmed, my experience is that for neutral elevator, even less right rudder is needed than if it were fixed, then, you can adjust for the desired line tension in the outside maneuvers, you adjust to have more right rudder with down elevator. I know Al will recommend to also trim to have more neutral rudder for the inside maneuvers. That will become a function of how well your model responds to the movable rudder. My experience as well as some others that have used the movable rudder even trim to use little rudder movement for the inside maneuvers to even giving a bit more right rudder. Rabe will probably tell you to ignore this. But, it becomes how the model responds in the maneuvers, particularly in the transition from outside to inside loops. The problem you might have is that with the position of the horns you have on the elevator/rudder linkage, you are fairly limited in what adjustments you can make to your rudder movement relative to the elevators. That linkage arrangement works for Al. I know it has not worked so well for me and some others that have seriously worked with this. (There are alternatives for that pushrod linkage.)
One of the problems for some who have tried the Rabe rudder is that they use excessive rudder movements from up and down elevator with unsatisfying results. Then they give up feeling the system is not helping.
Now, I will suggest that what I said may not apply to your model at all. I have seen Igor Burger use a lot of rudder offset on his electric Max Bee. But one factor is that his rudder is comparatively small and the rudder area is fairly well centered around the thrust line.
Yes, I have been lectured that many National and International Championships have been won without the use of a movable rudder. My only response to that is that it works for me and will continue to use it for my Open competition models.
As I suggested at the beginning of this post, if you already have experience with these things, and know what to expect, then disregard all of the above.
Keith
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Keith and ALL thanks so much for your thoughts in this thread. As you know from reading this thread I'm presently finishing up an ARC Strega and am learning so much.
I'm very lucky to have some well known "Experts" in our club. Recently I asked Danny Banjock about the rudder on his new Raven and he said he made it "adjustable" for trimming,but not a "wiggly rudder" as Joe Adamusko calls it. Now Joe Adamusko on the other hand who has been guiding me thru this project said "Skip put the Rabe Rudder on there". So I did thinking that if it didn't work out I could always fix it into position per Danny! So I'm hedging my bets here.
I did enlarge the stock rudder and fin as per Windy's tape suggestion. Setting up the rudder with the horns and linkage was no sweat. At full "up" my rudder is centered, at full down the rudder has plenty of deflection to the outside of the circle.....maybe too much. I'm on the outer most hole on my rudder horn. I might have to use a longer horn to restrict movement. I'm very anxious (in a good way) to see how the plane flies with this "wiggly" rudder.
Photos to follow when I get back in the shop tomorrow....PhillySkip
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A lot of my past stunters and some I'm building now have adjustable rudders. They nearly always wind up with little or no deflection after trimming. I have seen Keiths set up for the Rabe rudder linkage and have seen him use it very effectively. My early attempts with the Rabe rudder were total calamities and all wound up being fixed at neutral!
Yes I know they can work but they also can be a terrible deterrent to proper trimming!
Just my experience and yours may vary! If I ever decide to try one again it will use Keiths linkage, because it's more controllable and variable in my opinion!
Randy Cuberly!
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I did enlarge the stock rudder and fin as per Windy's tape suggestion. Setting up the rudder with the horns and linkage was no sweat. At full "up" my rudder is centered, at full down the rudder has plenty of deflection to the outside of the circle.....maybe too much. I'm on the outer most hole on my rudder horn. I might have to use a longer horn to restrict movement. I'm very anxious (in a good way) to see how the plane flies with this "wiggly" rudder.
Photos to follow when I get back in the shop tomorrow....PhillySkip
It sounds like you have not used a "Rabe Rudder" before and you said you increased the size of the rudder on your ship. My only comment would be that it is easy to use way too much rudder throw. I think that is the problem that many who have tried it and found they did not like it, discarded the idea and then go on to say it does not work. On my Rabe Bearcat, my rudder differential was no more than 3/16" difference from full down to full up. (And full control up and down is probably never applied in the pattern.) But the Bearcat is sort of a different animal because it has a relatively tall rudder and it all sets above the thrust line. On my other ships with more "conventional" rudder configurations have used a bit more throw.
Again, I would suggest to use no more or even less offset at neutral elevator for first flights than you would use on a fixed rudder ship.
I can attest that for the stunt ships I have built with the Rabe rudder concept, that once it is properly adjusted, it is assuring to know that there will be adequate line tension in all of the vertical and overhead outside maneuvers. It sometimes takes a while to find that adjustment/trim, but it is enough for me to never build an Open ship without it.
Keith
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Great memory Skip. Your are right I am the guy. This is me flying at 2016 Brodak's with a borrowed TF Tutor 1. The first time I flew the plane was in a competition and no practice flight or anything. After John Wright release the plane It was the first time I didn't know what to expect. Since then we refer to the plane as "Cold Turkey". Photo was taken by Will Hubin.
Charles Carter
Right before the " cold turkey " flight , I was making my rounds to check on things at the fly in, I noticed a little problem on the advanced circle, I went to the center of the circle to see if could help.
The problem was Charles could not get he safety thong on , his hand was too big for the lanyard , I asked if it had changed since last flight , she said he had never flown it before ... I had to watch this flight ... He did a unbelievable job, flew well and got better all thru the Pattern .
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Keith ,thanks and I promise to keep the movement to a minimum to start!....BTW I'd love to build your FW 190 one day!....PhillySkip
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Keith ,thanks and I promise to keep the movement to a minimum to start!....BTW I'd love to build your FW 190 one day!....PhillySkip
There are two versions. The 68 version is the one that won the 70 Nats and is what is in the Eric Rule kit. There is a 76 version (shows Rabe influence and uses the Rabe rudder concept) that placed at the 76 and 78 Nats. One of these may be flying at this next VSC.
We will need to talk when you get ready for something like this. I can send photos if you are interested.
Really, I am trying not to hijack this thread.
Keith
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Hi Keith,
We have met a couple times and you have always been a gentleman of the our sport. One time that comes to mind is the Golden State Stunt Championship 2013 Thank you for your help regarding the Rabe rudder setup on my Strega. I am still trimming the plane in other areas at the moment. I have been working on engine runs Also been working on how the Strega turns. I will sometime turn more attention to the Rabe rudder.
Charles C
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I think a Strega that looked like a Mustang would be neat. A fin, rudder and dorsal that is P-51 will be nice.
Chris...
Thats what I kinda tried to do with mine.
(http://i20.photobucket.com/albums/b210/ProETNova/IMG_0072B_1.jpg) (http://s20.photobucket.com/user/ProETNova/media/IMG_0072B_1.jpg.html)
(http://i20.photobucket.com/albums/b210/ProETNova/IMG_0192B_1.jpg) (http://s20.photobucket.com/user/ProETNova/media/IMG_0192B_1.jpg.html)
(http://i20.photobucket.com/albums/b210/ProETNova/new%20strega15.jpg) (http://s20.photobucket.com/user/ProETNova/media/new%20strega15.jpg.html)
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Right before the " cold turkey " flight , I was making my rounds to check on things at the fly in, I noticed a little problem on the advanced circle, I went to the center of the circle to see if could help.
The problem was Charles could not get he safety thong on , his hand was too big for the lanyard , I asked if it had changed since last flight , she said he had never flown it before ... I had to watch this flight ... He did a unbelievable job, flew well and got better all thru the Pattern .
Will,
Thank you so much for bringing back to remembrance that fact about the safety thong on the first flight! I had completely forgotten about the safety thong mishap. Talk about adding to my anxiety I already had about flying this plane for the first time and on top of that being at my biggest contest. How do you say EXCITED!
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Thats what I kinda tried to do with mine.
(http://i20.photobucket.com/albums/b210/ProETNova/IMG_0072B_1.jpg) (http://s20.photobucket.com/user/ProETNova/media/IMG_0072B_1.jpg.html)
(http://i20.photobucket.com/albums/b210/ProETNova/IMG_0192B_1.jpg) (http://s20.photobucket.com/user/ProETNova/media/IMG_0192B_1.jpg.html)
(http://i20.photobucket.com/albums/b210/ProETNova/new%20strega15.jpg) (http://s20.photobucket.com/user/ProETNova/media/new%20strega15.jpg.html)
Jared,
You have a beautiful "Strega". I remember when you first posted pics of it Stunt Hanger I was inspired to do my best effort on my "Strega". I really like the dorsal fin and belly pan on your "Strega". In addition to being inspired by you to put a dorsal fin and larger rudder on my "Strega" I would have also put a belly pan on mine if I wasn't in such a hurry to get mine done. Again thank you for you sending me an image of your rudder and your help and input you gave me on my "Strega"
Charles C