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General control line discussion => Open Forum => Topic started by: Joe Yau on February 28, 2014, 04:34:58 PM
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I have this plane that seems to be light on line tension on part of the RWO maneuver.. It is fine on the upwind side on the initial vertical climb to near the top, then the line tension gets light or sometimes free air to about 45 degree point (down wind side) then it's fine, and same thing second time around. I know its sort of strange.. usually the line tension goes light at 45 degree before the top.. I haven't tried anything yet, but I've added 2 grams of tip weight, and will have to wait till the weather clears again for the test flight. meanwhile I'm just wondering if there is anything else I should try? or what cause this.
Thanks in advance
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Joe these are sometimes guess work when you can't actually see or feel what's going on but I think it is one or more of the following.
1. Maybe just to slow. Or maybe need a bit more speed to overcome the other issues.
2. Too much fuselage area behind the CG. It's lifting the rear fuselage and weathervaining as you cross the top and wind gets under the rear fuse.
3. Too nose heavy. With not enough speed the nose is dropping past the top.
4. Lead out position is too far forward.
Obviously the answer may be in reversing some of the above a little at time and one it at a time until you find a better trim solution. Do the easy stuff first. Resist the urge to crank in a lot of rudder. Just be sure it's not going the wrong way. A little rudder ( maybe 5 degrees) to the outboard isn't too detrimental. My real suspicion is its there in 2 and 3 above. You might try getting the CG back a little and narrowing your handle line spacing to compensate.
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Joe these are sometimes guess work when you can't actually see or feel what's going on but I think it is one or more of the following.
1. Maybe just to slow. Or maybe need a bit more speed to overcome the other issues.
2. Too much fuselage area behind the CG. It's lifting the rear fuselage and weathervaining as you cross the top and wind gets under the rear fuse.
3. Too nose heavy. With not enough speed the nose is dropping past the top.
4. Lead out position is too far forward.
Obviously the answer may be in reversing some of the above a little at time and one it at a time until you find a better trim solution. Do the easy stuff first. Resist the urge to crank in a lot of rudder. Just be sure it's not going the wrong way. A little rudder ( maybe 5 degrees) to the outboard isn't too detrimental. My real suspicion is its there in 2 and 3 above. You might try getting the CG back a little and narrowing your handle line spacing to compensate.
Thanks Dave.
Some really good pointers.. It does feels like is #2 and maybe #3, or both. and increasing the speed will usually cure most issues #1. The design does have a fairly long/large surface area on the rudder (Primary Force), and because it is a flapless ship, the CG is more forward then my other planes. and it is at the edge of nose heavy to o.k.. will have play with the CG as well, and maybe a little right rudder. H^^
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Thanks Dave.
Some really good pointers.. It does feels like is #2 and maybe #3, or both. and increasing the speed will usually cure most issues #1. The design does have a fairly long/large surface area on the rudder (Primary Force), and because it is a flapless ship, the CG is more forward then my other planes. and it is at the edge of nose heavy to o.k.. will have play with the CG as well, and maybe a little right rudder. H^^
Joe,
You're on the right track by increasing the tip weight. That almost always increases overhead tension. The downside, of course, is that too much will cause other problems like dropping the outboard tip on squares etc.
I have to say nix to the rudder...that typically doesn't help much overhead...it might even make things worse.
Not knowing how the airplane is set up makes it difficult to make anything but generalizations about the trim problems. Where are the leadouts in relation to the CG? How long are your lines and what are your lap times. What engine and prop are you using.
Most often moving the leadouts FORWARD will increase line tension above 45 degrees...of course that is somewhat dependant on where they are now relative to the CG...Given what you've said I would NOT move them back first.
A little tail weight to put the CG where it belongs is also in order.
Randy Cuberly
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Joe,
You're on the right track by increasing the tip weight. That almost always increases overhead tension. The downside, of course, is that too much will cause other problems like dropping the outboard tip on squares etc.
I have to say nix to the rudder...that typically doesn't help much overhead...it might even make things worse.
Not knowing how the airplane is set up makes it difficult to make anything but generalizations about the trim problems. Where are the leadouts in relation to the CG? How long are your lines and what are your lap times. What engine and prop are you using.
Most often moving the leadouts FORWARD will increase line tension above 45 degrees...of course that is somewhat dependant on where they are now relative to the CG...Given what you've said I would NOT move them back first.
A little tail weight to put the CG where it belongs is also in order.
Randy Cuberly
Hi Randy,
The plane is pretty much in trim other then that one issue.. It has a Evolution .36 with a 3-blade Tornado 10x4. (launch at 9000rpm) Lines are .015 /61.5' i-i, the CG is at 2 3/16" from LE. leadout are 1" behind the CG. I wasn't going to add offset to the rudder unless it's really necessary.. as it had a slight yaw issue before, and moving the LO forward helped. I guess will have to see if the tip weight works or not before trying something else. Thx H^^
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Hi Randy,
The plane is pretty much in trim other then that one issue.. It has a Evolution .36 with a 3-blade Tornado 10x4. (launch at 9000rpm) Lines are .015 /61.5' i-i, the CG is at 2 3/16" from LE. leadout are 1" behind the CG. I wasn't going to add offset to the rudder unless it's really necessary.. as it had a slight yaw issue before, and moving the LO forward helped. I guess will have to see if the tip weight works or not before trying something else. Thx H^^
Joe,
Give us some info on the airplane. If it's a well known design some people might have some first hand experience. Just knowing its size, weight, configuration (flapped/unflapped etc.) would be of benefit. How far apart are the leadouts and where are you measuring their distance aft of the CG: to one or the other leadout? to the midpoint between them? etc.
Off the first read however I'd question 9K revs on a four pitch prop. Most any more or less four pitch I've worked with has required a minimum of 97-9800 or so to move the freight. Unless the engine is picking up considerable RPM at launch 9K is unlikely to be a good setting for it. I've no experience with the Evolution engine so can't predict what might be happening with it.
Ted
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First, I'd suggest a different prop. From my experience, those Tornado 3 blade props don't work well. Try the TT Cyclone 11 x 4.5 and launch at about 9.5k to 9.7k.
Add more tip weight. Add 1/4 oz and see if there's a change. If it's better, add another 1/4 oz. When it starts throwing the tip, start taking weight out. Some really good fliers (i.e., not me) will be able to tell the difference of 2-3 gram changes, but for most of us, 1/4 oz changes are at least noticeable. Eventually, we might want to revisit the tipweight and get more precise.
FWIW, I had the same problem with my "OPP" Eagle. Added three 1/4 oz weights in the tip box so far...at least it's safe, and my skilled (and highly paid) observer says it's not "throwing the tip" on hard corners. D>K Steve
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First, I'd suggest a different prop. From my experience, those Tornado 3 blade props don't work well. Try the TT Cyclone 11 x 4.5 and launch at about 9.5k to 9.7k.
This is the first item I would try, you never did tell us what your lap times were. First indication of a wimpy powered airplane or one flying too slow is loosing line tension overhead.
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Joe,
Give us some info on the airplane. If it's a well known design some people might have some first hand experience. Just knowing its size, weight, configuration (flapped/unflapped etc.) would be of benefit. How far apart are the leadouts and where are you measuring their distance aft of the CG: to one or the other leadout? to the midpoint between them? etc.
Off the first read however I'd question 9K revs on a four pitch prop. Most any more or less four pitch I've worked with has required a minimum of 97-9800 or so to move the freight. Unless the engine is picking up considerable RPM at launch 9K is unlikely to be a good setting for it. I've no experience with the Evolution engine so can't predict what might be happening with it.
Ted
The plane is a Sig Primary Force / flapless profile. (Pic below) Weights 41oz, LO are spaced 1 1/8" apart. and the 1" was measured at the mid point between them.
On the prop.. I had an APC 11x4 that worked quite well, but its heavy. (launch rpm was 9400), and I also have used a Xoar 11x4 wood prop. launch at about 9400rpm as well. The Tornado is a wide blade 3-blade, so the rpm is slightly lower for about the same lap time. I like it around 9000rpm, but I do bring it up to 9150 or so in windy conditions. ( 5.25/ lap on 61.5' i-i) H^^
(http://img.photobucket.com/albums/v612/JOE91SC/20140227_122252b_zps71f373e3.png) (http://smg.photobucket.com/user/JOE91SC/media/20140227_122252b_zps71f373e3.png.html)
First, I'd suggest a different prop. From my experience, those Tornado 3 blade props don't work well. Try the TT Cyclone 11 x 4.5 and launch at about 9.5k to 9.7k.
Add more tip weight. Add 1/4 oz and see if there's a change. If it's better, add another 1/4 oz. When it starts throwing the tip, start taking weight out. Some really good fliers (i.e., not me) will be able to tell the difference of 2-3 gram changes, but for most of us, 1/4 oz changes are at least noticeable. Eventually, we might want to revisit the tipweight and get more precise.
FWIW, I had the same problem with my "OPP" Eagle. Added three 1/4 oz weights in the tip box so far...at least it's safe, and my skilled (and highly paid) observer says it's not "throwing the tip" on hard corners. D>K Steve
The Tornado prop seems to work quite well in this set up.. the biggest difference I notice is the corners are much smoother comparing to the APC. and seems to have good line tension everywhere other then part of the RWO maneuver.. HB~> I actually got less line tension from the Xoar. D>K
First indication of a wimpy powered airplane or one flying too slow is loosing line tension overhead.
I don't think this is the case.. as I have good line tension on the OH-8, just part of the RWO was an issue. Lap time was around 5.25.
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Did it do the same thing happen with the APC? D>K Steve
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Did it do the same thing happen with the APC? D>K Steve
It still goes light at times when the wind kicks up (same spot). :( but the APC does have the best loc-on in level flight feel.. which I like. :)
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Joe,
Since I understood you to say that this occurs when the wind "kicks up", can you tell me where relative to dead up wind you enter the wingover. If it's dead upwind or slightly past up wind this line tension problem will nearly always occur.
Enter the wingover just slightly befor dead up wind...maybe 3-5 degrees before that point and the line tension will remain much more stable. This is a truism that I learned from Bob Whitely many years ago...try it.
Obviously this applies to tension lost when the wind is blowing. If the situation occurs in calm air then it is another trim problem such as those discussed before.
I do have to say that your statement that the airplane is well trimmed but loses line tension really doesn't make sense to me. Well trimmed airplanes don't lose line tension except possibly under the circumstance I mentioned above.
Randy Cuberly
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This may be a little off topic, but where do you measure (say for the LineIII program) the leadout position. Front line, rear line or average of the two?
Rick
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This may be a little off topic, but where do you measure (say for the LineIII program) the leadout position. Front line, rear line or average of the two?
Rick
Center between the two!
Randy Cuberly
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can you tell me where relative to dead up wind you enter the wingover. If it's dead upwind or slightly past up wind this line tension problem will nearly always occur.
It is possible that it is dead upwind or slightly passed.
Enter the wingover just slightly befor dead up wind...maybe 3-5 degrees before that point and the line tension will remain much more stable. This is a truism that I learned from Bob Whitely many years ago...try it.
much appreciate the tip.. H^^ I'll give that a try as well.
Obviously this applies to tension lost when the wind is blowing. If the situation occurs in calm air then it is another trim problem such as those discussed before.
There's no problem in calm air. The plane is quite well behaved through out the whole pattern. :) maybe just on the consecutive maneuvers, when the plane flys through it's own wake.. and I have to step back.
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Thanks for all the replies.. H^^
Lots to think about.. CG, LO, prop, etc.. will check the tip weight first, fly 5-7 degrees pass fly 3-5 degree before the direct upwind for the RWO and see how that goes.
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This is the first item I would try, you never did tell us what your lap times were. First indication of a wimpy powered airplane or one flying too slow is loosing line tension overhead.
Something strange is going on with the engine for sure. Ted (as usual) is absolutely right, there is something odd if you have to launch at 9000 rpm to get a reasonable lap time. The Tornado 3-blades (the black GRP types, anyway) are excellent props and a pretty light load for this engine, so I would expect even a higher-than-normal launch RPM due to lack of unload. It sounds as if it unloads a huge amount, which doesn't sound right at all, like the engine is wimpy for some reason. Maybe the venturi is too small, perhaps? I think the Rustler-Merco 40 Metamorph launches at maybe 96-9700 with the same prop, and it's 4-stroking.
Nonetheless, it also show some classic signs of yawing inboard. At this point, even *I* would try adding a tiny bit of rudder offset and then adjusting the leadouts for minimum yaw reaction in squares, then see if it improves. I would also check that the fuselage is straight right before every flight. Profiles are absolutely notorious for not having stable alignment over environmental changes, in particular, they tend to bend like the metal thing in your wall thermostat if the Sun is on one side for any length of time. We have some unfortunate experiences with that, too.
Brett
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It is possible that it is dead upwind or slightly passed.
much appreciate the tip.. H^^ I'll give that a try as well.
There's no problem in calm air. The plane is quite well behaved through out the whole pattern. :) maybe just on the consecutive maneuvers, when the plane flys through it's own wake.. and I have to step back.
Joe....I said 3-5 degrees before dead upwind...not past!
Randy Cuberly
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Something strange is going on with the engine for sure. Ted (as usual) is absolutely right, there is something odd if you have to launch at 9000 rpm to get a reasonable lap time.
I hope I'm not hijacking Joe's thread too much here -- but I launch an OS LA 46 with a 12.25x3.75 prop at 9050 RPM. It audibly speeds up to a fast two-stroke for the first lap, then settles down to barely-not-four-stroke, two-stroke run for all but the last few laps where it speeds up again.
And I'm loving the flights, and doing well enough to get respectable 'middle of the pack' scores in Advanced with it.
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Something strange is going on with the engine for sure. Ted (as usual) is absolutely right, there is something odd if you have to launch at 9000 rpm to get a reasonable lap time. The Tornado 3-blades (the black GRP types, anyway) are excellent props and a pretty light load for this engine, so I would expect even a higher-than-normal launch RPM due to lack of unload. It sounds as if it unloads a huge amount, which doesn't sound right at all, like the engine is wimpy for some reason. Maybe the venturi is too small, perhaps? I think the Rustler-Merco 40 Metamorph launches at maybe 96-9700 with the same prop, and it's 4-stroking.
Not sure if this makes any difference.. The Tornado prop is actually labeled as a "10x6". but it measures out to 4" at the tip, and 5" at station 6 on the Prather guage, I put it on the plane and it performs close to a 4" pitch then a 6".
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Joe....I said 3-5 degrees before dead upwind...not past!
Randy Cuberly
Thanks for pointing that out. not too awake on a Monday I guess.. HB~>
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Not sure if this makes any difference.. The Tornado prop is actually labeled as a "10x6". but it measures out to 4" at the tip, and 5" at station 6 on the Prather guage, I put it on the plane and it performs close to a 4" pitch then a 6".
Ah! That does make a difference, a huge one. I would say it is performing like a 10-6, by not having particularly good vertical performance.
Brett
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I hope I'm not hijacking Joe's thread too much here -- but I launch an OS LA 46 with a 12.25x3.75 prop at 9050 RPM. It audibly speeds up to a fast two-stroke for the first lap, then settles down to barely-not-four-stroke, two-stroke run for all but the last few laps where it speeds up again.
And I'm loving the flights, and doing well enough to get respectable 'middle of the pack' scores in Advanced with it.
its frikken amazing what a prop can do huh Tim
no seriously,, not poking at you,,
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I hope I'm not hijacking Joe's thread too much here -- but I launch an OS LA 46 with a 12.25x3.75 prop at 9050 RPM. It audibly speeds up to a fast two-stroke for the first lap, then settles down to barely-not-four-stroke, two-stroke run for all but the last few laps where it speeds up again.
And I'm loving the flights, and doing well enough to get respectable 'middle of the pack' scores in Advanced with it.
9050 RPM with a 3.75 pitch prop....That seems really odd. How long are your lines?
Typically on any of a half dozen airplanes I've flown or seen flown with prop pitches that shallow need something between 10,000 to 10,500 RPM to fly a reasonable speed.
I suspect that your engine must be really unloading in the air and picking up about 12 to 1500 RPM.
What size venturi are you running on the 46?
Curious,
Randy Cuberly
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He may have very dense air also. LL~ LL~ LL~
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Ah! That does make a difference, a huge one. I would say it is performing like a 10-6, by not having particularly good vertical performance.
Brett
So the 4" pitch on the APC is huge difference vs 4" pitch on the Tornado prop (both measured at the tip)? I did notice the Tornado prop is slightly undercambered.. but no phillip entry.
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9050 RPM with a 3.75 pitch prop....That seems really odd.
I have come across an APC 12.25" x 3.75" that actually measures out to 4" pitch, both station #6 and at the tip. and a few that is really a 3.75 pitch. not sure if that's the case..
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So the 4" pitch on the APC is huge difference vs 4" pitch on the Tornado prop (both measured at the tip)? I did notice the Tornado prop is slightly undercambered.. but no phillip entry.
I was comparing the Tornado 10-4 that you said you had to the 10-6 you actually had. We have run both props and knew what they needed to do and that's why the numbers didn't look right to Ted and me. It's a lot more like it assuming it was a 10-6, that sound like it could be in the ballpark.
The camber makes a huge difference in the effective pitch, and the semi-symmetrical airfoil affects the measurement, at least. At the tip, particularly, the angle gauge greatly underestimates the effect of the camber. APC vs Tornado= apples and oranges.
By the way, don't overlook the second part of my answer above. With the prop/engine speed issue resolved, look at the rest of the trim.
Brett
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9050 RPM with a 3.75 pitch prop....That seems really odd. How long are your lines?
Typically on any of a half dozen airplanes I've flown or seen flown with prop pitches that shallow need something between 10,000 to 10,500 RPM to fly a reasonable speed.
I suspect that your engine must be really unloading in the air and picking up about 12 to 1500 RPM.
What size venturi are you running on the 46?
64 feet.
Yes, it's definitely unloading.
The venturi is, um, about that size -- it looks pretty much like others that I've seen, but with three layers of fine-mesh purple nylon net over it, 'cause that's what I needed to keep the engine from running away. I haven't looked down it's little throat since I got the plane dialed in last spring.
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I was comparing the Tornado 10-4 that you said you had to the 10-6 you actually had. We have run both props and knew what they needed to do and that's why the numbers didn't look right to Ted and me. It's a lot more like it assuming it was a 10-6, that sound like it could be in the ballpark.
I didn't know there was actually a 10-4 version.. I just went with what was measured.
Nonetheless, it also show some classic signs of yawing inboard. At this point, even *I* would try adding a tiny bit of rudder offset and then adjusting the leadouts for minimum yaw reaction in squares, then see if it improves. I would also check that the fuselage is straight right before every flight. Profiles are absolutely notorious for not having stable alignment over environmental changes, in particular, they tend to bend like the metal thing in your wall thermostat if the Sun is on one side for any length of time. We have some unfortunate experiences with that, too.
It already has a bit of right rudder (1-2 degree), and the fuse is quite straight. The LO was adjusted with the set rudder position. I guess I could try more rudder, but the plane flys fine as is. and has good line tension in all maneuvers other then part of the RWO in windy conditions.
(http://img.photobucket.com/albums/v612/JOE91SC/a0bae2e4-9422-4834-938d-33b73e2f62f9_zpsd64a8dc2.jpg) (http://smg.photobucket.com/user/JOE91SC/media/a0bae2e4-9422-4834-938d-33b73e2f62f9_zpsd64a8dc2.jpg.html)
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64 feet.
Yes, it's definitely unloading.
The venturi is, um, about that size -- it looks pretty much like others that I've seen, but with three layers of fine-mesh purple nylon net over it, 'cause that's what I needed to keep the engine from running away. I haven't looked down it's little throat since I got the plane dialed in last spring.
Tim Tim ,, thats like soldering a transistor into a PCB and saying,, well it looks just like the other ones,, sigh,,
now that we have you using a tack I suppose the next thing is to get you to look at your ventruri size,, D>K S?P
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Joe,
Chris is right near you. He should have a look to help you.
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I didn't know there was actually a 10-4 version.. I just went with what was measured.
It already has a bit of right rudder (1-2 degree), and the fuse is quite straight. The LO was adjusted with the set rudder position. I guess I could try more rudder, but the plane flys fine as is. and has good line tension in all maneuvers other then part of the RWO in windy conditions.
(http://img.photobucket.com/albums/v612/JOE91SC/a0bae2e4-9422-4834-938d-33b73e2f62f9_zpsd64a8dc2.jpg) (http://smg.photobucket.com/user/JOE91SC/media/a0bae2e4-9422-4834-938d-33b73e2f62f9_zpsd64a8dc2.jpg.html)
OK, Joe, I thought it didn't "fly just fine as is", hence you were asking for advice. I don't know what to tell you at this point, this was just my best guess.
In any case, flying of faster, or at least using less pitch at the same level flight speed, will likely improve this point in the pattern.
Brett
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Don't hesitate to have Alan take a test flight either!
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Don't hesitate to have Alan take a test flight either!
Perfect! Just figure out how to put the lead outs in the other wing. ;D
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Tim Tim ,, thats like soldering a transistor into a PCB and saying,, well it looks just like the other ones,, sigh,,
Uh -- that's not how it's done?
Boy, this could go a long way to explaining some problems I've seen.
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Perfect! Just figure out how to put the lead outs in the other wing. ;D
OK Mike, so you want everything perfect, and it's not even your plane!
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OK Mike, so you want everything perfect, and it's not even your plane!
Probably a habit I've picked up from the company I keep.
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Joe,
Chris is right near you. He should have a look to help you.
Hi Paul,
I haven't seen Chris or Alan at the field since New Year day's Polar bear fun-fly.. It must be the cold temp or something.
Don't hesitate to have Alan take a test flight either!
Oh yes.. I'm sure he would test fly it. HB~> LL~
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Actually, Paul let me fly his test bed piped ship back in the late 80's. If I remember, correctly, it was the day you came up on a Sunday to fly with Arden. It was the day he arrived from China. Paul flew his quickly assembled 4 stroke, as his Skywriter was still in his travel box.
Paul trusted me with it although he looked a bit concerned when I went out and picked up the handle upside down. I flew the whole pattern starting from inverted flight.
Alan
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Actually, Paul let me fly his test bed piped ship back in the late 80's. If I remember, correctly, it was the day you came up on a Sunday to fly with Arden. It was the day he arrived from China. Paul flew his quickly assembled 4 stroke, as his Skywriter was still in his travel box.
Paul trusted me with it although he looked a bit concerned when I went out and picked up the handle upside down. I flew the whole pattern starting from inverted flight.
Alan
Ah, just like Mike, who picks up the handle upside down every flight...on purpose. Jim Johnson also, IIRC.
As for Joe's "Primary Force"/Evo .36...I'd bet (Joe's) $2 that the TT Cyclone 11 x 4.5 would make a better combo than either the Tornado or the APC. And possibly more tipweight. In one of Ted's essays, he suggests adding more tipweight (among other trim changes) for a windy day. D>K Steve
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Joe,
Since I understood you to say that this occurs when the wind "kicks up", can you tell me where relative to dead up wind you enter the wingover. If it's dead upwind or slightly past up wind this line tension problem will nearly always occur.
Enter the wingover just slightly befor dead up wind...maybe 3-5 degrees before that point and the line tension will remain much more stable. This is a truism that I learned from Bob Whitely many years ago...try it.
Obviously this applies to tension lost when the wind is blowing. If the situation occurs in calm air then it is another trim problem such as those discussed before.
I do have to say that your statement that the airplane is well trimmed but loses line tension really doesn't make sense to me. Well trimmed airplanes don't lose line tension except possibly under the circumstance I mentioned above.
Randy Cuberly
Good catch, Randy. Joe's comments about the wind slipped by me because I didn't yet know enough about the airplane itself. Bob's advice is right on. Be interesting to see what Joe has to say about it (I'm reading this in order a few days late so will read on to see if you've scored!)
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I flew a primary force for a while. I built mine from Mike's plans and one of the first laser kits he made, but it should be pretty much the same plane.
I flew mine on an FP 25, LA 25, and an OS26 4s car motor on a tiny aluminum pipe with a tiny prop at an insanely high RPM. It worked but FP was the best option.
I flew on APCs of the 10" variety and the flattest pitch I could find. IIRC I think I had a 3 pitch. Making sure to run the engine in a mildly rich 2s on the ground with only a minor burp here and there in level flight throughout the pattern. No 2-4 stuff here. I ran Omega RC 10% nitro fuel and the FP LOVED IT!! My FP 40 ran its best on that stuff too. No, it's not stunt fuel but then again we aren't talking about a stunt engine either. Can't remember the RPMs off hand but it was well over 10K at launch. I wanted the RPMS as high as possible with the smaller motor keeping the engine in its designed power range. I don't know off hand the timing of the evo 36 but if they are near what their RC counter parts are then you would want the recommended fuel to get the most consistent run. Horizon says the operating range for the evo 36 is 9300 to 17000. You are just barely touching the operating range at take off. This may lead to what I describe below about speeding up.
Things to try...
Take a lap time right before the RWO. Then take it again after the round 8, and again after the clover. You are describing a situation where it is just too rich for the over head pass in the winds, especially if you miss the wind. The motor is still kind of cool at this point and has had no load placed on it yet. It's probably still breaking and sounding normal but it is still a tad rich. The lap times throughout will tell you right away if this is your issue. It may not feel that way on the handle as the flight progresses because the performance increases with speed/power and you are able to properly fly the plane. If you are getting a large speed up by the end of the tank, more than .03 tenths. You will want to look at how you have the tank plumbed or shimmed and see if you can get it down to .01-.02 speed up by the end of the flight.
I would also recommend taking the lines down to 60' i-i. This was the max length I could get before the model would start faulter. In your case you will go down on lap time to around 5 seconds but that wont be bad at that length. it would actually be pretty good especially if the lap times are consistant beginning to end. The increased speed will pull it through the RWO that much better.
I would recommend staying with the flattest APCs you can find, even if you have to go down in diameter, get the RPMs up, way up! With that restrictive muffler you can mimic a piped system with high RPMs and flat pitches. Run it 2-2 and you can hear the soundwave rattle on the ground before launch. It' works really good once you get it the right range.
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Thanks for all the replies.. H^^
Lots to think about.. CG, LO, prop, etc.. will check the tip weight first, fly 5-7 degrees pass the direct upwind for the RWO and see how that goes.
Joe!
No, no, no!!! You need to start before directly upwind. Your goal should be to have the airplane vertical at or just before directly upwind. In the case you've described I'd suggest having the "up track" slightly prior to directly up wind as you will find the wind actually gives you a boost up and over.
A number of years ago I wrote several consecutive Model Aviation Stunt columns entitled Fly Like a Champion that covers a lot of material about dealing with winds and other of Mother Nature's attempts to destroy our patterns. Send me a private message with your email address and I'll try to scan them and forward them to you.
ted
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A number of years ago I wrote several consecutive Model Aviation Stunt columns entitled Fly Like a Champion that covers a lot of material about dealing with winds and other of Mother Nature's attempts to destroy our patterns. Send me a private message with your email address and I'll try to scan them and forward them to you.
Post the issue dates? I'd like to read those, and if I don't have them in my archives I'll be able to snag them off the AMA site!
Thanks.
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Not sure if this makes any difference.. The Tornado prop is actually labeled as a "10x6". but it measures out to 4" at the tip, and 5" at station 6 on the Prather guage, I put it on the plane and it performs close to a 4" pitch then a 6".
Glad you clarified that, Joe. Didn't make sense if it was the Tornado 10X4 three blade. I used the 10X6 on some of my ships but mostly use the four pitch and have started doing so on my Ruffy since I went to higher nitro, all castor fuel with a bigger intake. The little Merco grew some balls after those changes. I launch in the vicinity of 10K and that's where the run described by Brett comes into play. It's strong and speed consistent. With the 10X6 it was just too fast to fly really well at an RPM that let the engine run with any gusto.
By the way, I've absolutely loved the way the Tornadoes have flown several of my classic ships, including the smushed Nobler, the Tucker Special and the Chizler all of which had good records at the VSC and Nats events, even winning a couple.
Ted
Ted
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Post the issue dates? I'd like to read those, and if I don't have them in my archives I'll be able to snag them off the AMA site!
Thanks.
Tim,
I'm at work right now saving the world from aviation disaster. When I get home I'll look it up in my um...er...sorta...library. I know they're there somewhere because I sent copies to Don Chandler a month or two ago. Send me a PM with your email, too, Tim.
Ted
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Joe!
A number of years ago I wrote several consecutive Model Aviation Stunt columns entitled Fly Like a Champion that covers a lot of material about dealing with winds and other of Mother Nature's attempts to destroy our patterns. Send me a private message with your email address and I'll try to scan them and forward them to you.
ted
I hope that Ted does not mind that I step in here and help him avoid his search through his vast archives of stunt lore and trivia.
Ted wrote the Stunt Column in Model Aviation from May 1984 through April 1990. His three-part series on "Fly Like a Champion" appeared in his column in the June, July and August 1986 issues of Model Aviation.
For those doing a search:
June 1986 started on page 63
July 1986 started on page 69
August 1986 started on page 69
About 10 pages in all.
Over the years, a common practice of the devoted people who wrote these stunt columns in the magazines was to devote several columns on flying the pattern. Ted's was one of the best.
Keith
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Thanks, Keith. I appreciate the assist! Can you actually search for MA ariticles at the AMA site?
Ted
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In any case, flying of faster, or at least using less pitch at the same level flight speed, will likely improve this point in the pattern.
Brett
I might repitch the prop to 3.75" but will see.
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Ah, just like Mike, who picks up the handle upside down every flight...on purpose. Jim Johnson also, IIRC.
As for Joe's "Primary Force"/Evo .36...I'd bet (Joe's) $2 that the TT Cyclone 11 x 4.5 would make a better combo than either the Tornado or the APC. And possibly more tipweight. In one of Ted's essays, he suggests adding more tipweight (among other trim changes) for a windy day. D>K Steve
Looks like there's a break in the weather from next Tuesday on.. :) If it's not too windy, I should be able to put in a few flights to check out the tip weight and go from there.
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I flew a primary force for a while. I built mine from Mike's plans and one of the first laser kits he made, but it should be pretty much the same plane.
I flew mine on an FP 25, LA 25, and an OS26 4s car motor on a tiny aluminum pipe with a tiny prop at an insanely high RPM. It worked but FP was the best option.
I flew on APCs of the 10" variety and the flattest pitch I could find. IIRC I think I had a 3 pitch. Making sure to run the engine in a mildly rich 2s on the ground with only a minor burp here and there in level flight throughout the pattern. No 2-4 stuff here. I ran Omega RC 10% nitro fuel and the FP LOVED IT!! My FP 40 ran its best on that stuff too. No, it's not stunt fuel but then again we aren't talking about a stunt engine either. Can't remember the RPMs off hand but it was well over 10K at launch. I wanted the RPMS as high as possible with the smaller motor keeping the engine in its designed power range. I don't know off hand the timing of the evo 36 but if they are near what their RC counter parts are then you would want the recommended fuel to get the most consistent run. Horizon says the operating range for the evo 36 is 9300 to 17000. You are just barely touching the operating range at take off. This may lead to what I describe below about speeding up.
Things to try...
Take a lap time right before the RWO. Then take it again after the round 8, and again after the clover. You are describing a situation where it is just too rich for the over head pass in the winds, especially if you miss the wind. The motor is still kind of cool at this point and has had no load placed on it yet. It's probably still breaking and sounding normal but it is still a tad rich. The lap times throughout will tell you right away if this is your issue. It may not feel that way on the handle as the flight progresses because the performance increases with speed/power and you are able to properly fly the plane. If you are getting a large speed up by the end of the tank, more than .03 tenths. You will want to look at how you have the tank plumbed or shimmed and see if you can get it down to .01-.02 speed up by the end of the flight.
I would also recommend taking the lines down to 60' i-i. This was the max length I could get before the model would start faulter. In your case you will go down on lap time to around 5 seconds but that wont be bad at that length. it would actually be pretty good especially if the lap times are consistant beginning to end. The increased speed will pull it through the RWO that much better.
I would recommend staying with the flattest APCs you can find, even if you have to go down in diameter, get the RPMs up, way up! With that restrictive muffler you can mimic a piped system with high RPMs and flat pitches. Run it 2-2 and you can hear the soundwave rattle on the ground before launch. It' works really good once you get it the right range.
Thanks for the insight/ tips.. H^^ I ran the Evo .36 in a wet 2-2 mode (video below shows a glimpse of the run with the 11x4 APC), that was launched at 9450rpm. as it was a bit windy that day. I will check the run a little more closely (compare lap time from beginning to end) on my next flying session to determine if its the prop or the trim.
http://youtu.be/3YxZgQkgDvY (http://youtu.be/3YxZgQkgDvY)
Joe!
No, no, no!!! You need to start before directly upwind. Your goal should be to have the airplane vertical at or just before directly upwind. In the case you've described I'd suggest having the "up track" slightly prior to directly up wind as you will find the wind actually gives you a boost up and over.
sorry.. I forgot to edit that. Randy has pointed that out earlier, so I was aware of that.
A number of years ago I wrote several consecutive Model Aviation Stunt columns entitled Fly Like a Champion that covers a lot of material about dealing with winds and other of Mother Nature's attempts to destroy our patterns. Send me a private message with your email address and I'll try to scan them and forward them to you.
ted
Much appreciate that.. H^^ PM sent
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From the looks of the wind streamer in the back ground, you have a lot of turbulence. I noticed the wings are wobbling a little.
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Joe...I sent you an email with a .wpd file attached. Hope you can open it ok. If not, let me know and I'll copy/paste it into another email. H^^ Steve
PS: Maybe Sparky could add .wpd to the acceptable file-type list?
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Joe...I sent you an email with a .wpd file attached. Hope you can open it ok. If not, let me know and I'll copy/paste it into another email. H^^ Steve
Thanks Steve. great infos! I just have to open it with the word program. :) I've repitched my second Tornado 3-blade to 3.75 pitch, and also reduced the middle station #5 to 4" pitch from stock 5". I should be able to run at slightly higher rpm. will see how that works out.
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From the looks of the wind streamer in the back ground, you have a lot of turbulence. I noticed the wings are wobbling a little.
Both of the local fields gets like that when the wind picks up to around 12km+ or so.
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I figured I oughta try to copy & paste the mysterious information I emailed to Joe. Not sure who this was written by but it was NOT Ted Fancher. It seemed to me that Joe's setup might be improved by working on some of these suggestions, particularly items 1, 2, 3 & 4. Especially note the thoughts about the wingover! Thanks to somebody for putting this stuff in writting to help the rest of us. y1 Steve
EDIT: Apparently, I got this article online from Australia or Europe. The takeoff position suggested for serious windy conditions is definitely not good. My own suggestion is about 15' prior to dead downwind, but opinions vary. Do what works for you!
"There are things you need to do to prepare for flying in high winds. Most important concept to remember is that stunt flying is ALL about energy management. Converting kinetic energy into potential and back. Energy management is critical when flying in windy conditions. Here's what works for me:
Setup:
1) Don't bother flying nose heavy models in high winds. There is no way around this: the further forward CG(Center of Gravity) from CL(Center of Lift), the larger the arm of force, the mode wind will push the model around. Make sure models have CG where designer intended them. If unsure where it it should be, balance the model so that CG is 6-12mm in front(can someone verify that it's in FRONT and not BEHIND, I'm always fuzzy about this) of CL.
2) Never trim in high winds. Make sure to trim the model when winds are less than 5km.
3) if you are using 3 blade prop, switch to larger diameter 2-blade prop with SQUARE tips.
4) increase launch RPM's to get .1-.2 faster lap times.
Flying maneuvers:
Takeoff: This is BAD ADVISE for any serious wind! See my note in bold above. Steve
Launch so that the wind is in the back of the model. The idea is have wind help the model accelerate(build up energy) on the downwind side(right side) of the circle. The goal is to get airborne just before you cross over from downwind to upwind side of the circle. The reason for doing it before crossing over is that you will need to establish gradual climb before you get to the up wind side. Once you're on the upwind side, the model will begin to slow down. slow = poor response to control inputs. If you are not established on the climb out, it will be difficult to change direction on the upwind side. As a general rule, the model will respond slower to control inputs on the upwind side of the circle.
Level flight:
There is not much to do here but to prepare for one of the most difficult maneuvers: wingover. To do that, you need to build up momentum. Start accelerating the model by walking backward in circle, keeping the model in font of you. The last lap before the wingover you should be walking backward as fast as possible without tripping over.
Wingover
This is the most difficult maneuver because the model is heavy(full of fuel) and has forward CG. Make soft entries into turns 1 and 3.The entry should be as if you are starting a round circle rather than a typical square entry. Another critical component is to enter directly upwind. You have to abandon the notion that you can steer the model in high winds. No amount of corrections will make the model fly straight wingover if you did not enter directly downwind. If you miss the turn and the model starts move sideways, accept the error and fly the rest of the maneuver in the direction the wind is blowing.
Inside and outside round loops, Inside square loop
Flying round loops directly downwind will cause the model to move faster and faster with every loop. This is called the "windup" and it may cause the model go so fast that it will fly into the ground. Key here is to avoid windup by biasing the center of loops to the left of the downwind for inside loops and to the right for the outsides. Amount of bias is directly proportional to how high the winds are. More wind, more bias. Start by flying insides 3m past direct downwind. If you get the amount of bias correct, the model will fly loops as if there is no wind! Oh yes, one critical detail: NEVER FLY above 45 degrees!!! think of 45 as "do not cross" line. If you do, the lines will go slack and the model will be at the mercy of Boreas, the God of the Wind!
Outside Squares
Same bias rules apply as with round loops. At the entry into the maneuver, the model will be going very fast. Turning down will make it go even faster. There is very little you can do so be prepared to turn hard and quick. There is one very good trick to lower the entry speed to somewhere manageable: do not start climb to enter outsides until you are on the downwind side of the circle. Speed loss due to the climb will offset the speed gain provided by the wind on the downwind side. The steeper the climb, the slower the entry will be. Don't make it too slow though: slow = lack of control.
Triangle
Bias just like you would with rounds. The first turn will be on the upwind side and the wind will make the model turn harder that usual so there is no need to make that hard first turn. Let wind help you. The less you turn, the more energy you will have for turn 3.
Horizontal round and square 8
DO NOT BIAS! DO NOT FLY ABOVE 45! These maneuvers should be directly down wind. Be prepared for the model to slow down significantly at the top and adjust your timing accordingly. Most pilots develop a rhythm for squared 8's: evenly spaced turn, turn, turn. That rhythm is your enemy in high winds! Fly by watching position of the model instead.
Vertical 8
This seems to be the most difficult maneuver for most pilots because most pilots fly large inside loop which places the outside loop past 90 degrees. Past 90, there is not just the wind slowing it down, the wind s actually pushes it DOWN towards you! The key here is to keep inside loop tight below 45, directly downwind. Remember the wind up issue when flying round loops directly down wind? Well, here we NEED that wind up to build energy for the outside top loop! Another key element here is to keep line tension up. One way to do it is to shorten the lines. I typically fly with my hand almost extended. When flying the outside loop, I bring the handle closer to my chest and begin to I will begin to kneel on one knee. What this does is decrease the radius of the circle the model flies which increases line tension. Stand back up and move the hand to regular position for the down side.
Hourglass
Unlike other maneuvers that have just one or two tricks to keep flying, hourglass needs 5 tricks!
1) Build up energy by walking backwards like just like you did for the wingover. slowly build up the speed, so that you are walking the fastest during the last 1/4 lap before turn 1.
2) make a shallow turn up. Since turn 1 takes place on the upwind side, the wind will make the turn steeper than usual so you need to account for it.
3) The wind will push the model after turn 1 and will help the model speed up. At this point you need to build your energy for turns 2 and 3. Extend you arm completely if possible
4) As you approach turn 2, the lines will begin to slack and you will not be able to make that turn unless you keep the tension up! Start contracting your arm and kneel. Shortening the flying radius transfers built up energy into model speed and line tension.
5) Turns 2 and 3 should be done very quickly one after the other. Turn 2 forces the model to turn hard into the wind which kills most of the energy. The more you stay up there the slower the model will get.
After turn 3, the model will be traveling down plus be pushed by the wind. This will translate into a lot of speed. Turn 4 will come very quick and suddenly. You need to keel the energy. Stand back up and extend your arm. If the wind is really strong, I go as far as make a step forward..
Overhead 8
Make a gradual entry from level flight. The key here is not to loose energy on the way up. Spend as little time flying into the wind by keeping the loops tight. Most pilots fly big overhead loops. DO NOT DESCEND BELOW 45!!! Large loops mean very long flight into the wind! Another trick is to contract the arm/kneel when flying into the wind and to release/stand on the downwind side of the loops. It is also VERY IMPORTANT that you fly the maneuver DIRECTLY overhead. This is again has to do with how much time you spend flying into the wind.
Clover
There is little you can do to keep the tension. All you have is make sure you don't cross 90 degrees on loops 1 and 3. Contract arm/kneel as needed to keep line tension, stand/release when wind is pushing the model to store the energy. On the final climb out, the model has lost the most energy, it's climbing AND flying into the wind. This is where models get lost. As soon as you cross 90 degrees, the maneuver is over and you can start the turn downwind.
Landing
Try to land on the down wind side as the wind as this will be where line tension is the highest.This is important since the model will start moving INTO the wind and will try to lift off. you need line tension to keep the model down on the ground. I usually aim for 5m before directly downwind as my landing point."
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Takeoff:
Launch so that the wind is in the back of the model. The idea is have wind help the model accelerate(build up energy) on the downwind side(right side) of the circle. The goal is to get airborne just before you cross over from downwind to upwind side of the circle. The reason for doing it before crossing over is that you will need to establish gradual climb before you get to the up wind side. Once you're on the upwind side, the model will begin to slow down. slow = poor response to control inputs. If you are not established on the climb out, it will be difficult to change direction on the upwind side. As a general rule, the model will respond slower to control inputs on the upwind side of the circle.
I thought I might add a little input here.
If you decide to take off with the wind on the back of the model be prepared that any up elevator before model is at speed will tip it over and eat the prop. I have seen this time and time and time and time and time again at all levels of flying from the nats top 20 day down to the weekend sport session. So many carbon props, many that can't be duplicated, torn up during this type of launch. Wind from behind the model hinders the surfaces effectiveness. They actually work opposite of what they are supposed to do.
What works for me on high wind days is to take off dead down wind or just a few feet past dead down wind. Prior to release level the elevator and keep the model level as it comes up to speed. The wind will help it lift off ground faster than normal but you will have control over it with a simple step back if needed. Or you can feed a little down into it and keep it on the ground until it is up to speed and then lift off. You have to be off of the ground prior top 1/4 lap anyway so you can be up before the wind is directly into the models face. I was once told a very long time ago these "These things were built to fly so get it in air, QUICKLY!"
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I might repitch the prop to 3.75" but will see.
Hi Joe, I know a little about this design (LOL). Lots of very good flyers are giving you excellent advise.
(1) I would suggest that you put the leadouts in the location indicated in the instruction book, then add 1/4 ounce of additional tip weight. (At 1 ounce of tip weight you should see the outboard wing drop in a triangle or square loop. If not, add another 1/4 ounce of tip weight until it dose just that. Then remove small amounts of tip weight until the wing drop is gone).
(2) Change the prop to a 11" X 4, the lap times of the P-Force need to be around the 5.0 to 5.2 for best performance. The Grish black 10" X 4" is a great prop so if you can find one, by all means get one and try it. The best prop that I found for a .36 is the Bolly 10.5" X 4.25 undercamber (killer).
(3} C.G. The C.G. should be around 2" back from the leading edge. At 2-5/16" it will be a little jumpy and not groove as well
(4) The line length should be around 61' to 62' from the center of the model to the center of the handle.
(5) Handle spacing on my P-Force was set at 3.75" for the best overall feel.
(6) Rudder offset is between 0 and a max of 1/8" to the out board side.
If you have the chance to let Allen fly it I'm sure he will come up with many of the same ideas and suggestions.
Later,
Mike Pratt (Mikey)
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Listen to Mikey and you will have one terrific flying plane. I got mine as a short kit with plans years ago at a VSC. It is my go to plane when I want to get serious. I know it is my best flying plane powering with an OS LA .25, using a power point 10-4. Some times an APC 10-4 goes on in really windy weather. I fly 60 foot .015 cable using a Fancher handle. Right now it needs recovering after the demented poodle did her dance on the wing at Topeka one year.
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I don't want to hijack this thread, but it's been a long time since hearing from you Mike. Where are you now and how are you doing?
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I don't want to hijack this thread, but it's been a long time since hearing from you Mike. Where are you now and how are you doing?
Yeah Mike...I second that. How about a post telling us all what's up with you.
I don't want to get "Soupy", but we've missed you buddy!
Randy Cuberly
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I figured I oughta try to copy & paste the mysterious information I emailed to Joe. This was written by Mr. Ted Fancher, FYI. It seemed to me that Joe's setup might be improved by working on some of these suggestions, particularly items 1, 2, 3 & 4. Especially note the thoughts about the wingover! Thanks to Ted for putting this stuff in writting to help the rest of us. y1 Steve
Thanks again Steve. H^^ This is a much clearer version then the emailed one.
I don't want to argue with Ted's writings but I thought I might add a little input here.
If you decide to take off with the wind on the back of the model be prepared that any up elevator before model is at speed will tip it over and eat the prop.
Good point! I've seen that happen to others, and has happened to me as well.
Hi Joe, I know a little about this design (LOL). Lots of very good flyers are giving you excellent advise.
(1) I would suggest that you put the leadouts in the location indicated in the instruction book, then add 1/4 ounce of additional tip weight. (At 1 ounce of tip weight you should see the outboard wing drop in a triangle or square loop. If not, add another 1/4 ounce of tip weight until it dose just that. Then remove small amounts of tip weight until the wing drop is gone).
(2) Change the prop to a 11" X 4, the lap times of the P-Force need to be around the 5.0 to 5.2 for best performance. The Grish black 10" X 4" is a great prop so if you can find one, by all means get one and try it. The best prop that I found for a .36 is the Bolly 10.5" X 4.25 undercamber (killer).
(3} C.G. The C.G. should be around 2" back from the leading edge. At 2-5/16" it will be a little jumpy and not groove as well
(4) The line length should be around 61' to 62' from the center of the model to the center of the handle.
(5) Handle spacing on my P-Force was set at 3.75" for the best overall feel.
(6) Rudder offset is between 0 and a max of 1/8" to the out board side.
If you have the chance to let Allen fly it I'm sure he will come up with many of the same ideas and suggestions.
Later,
Mike Pratt (Mikey)
Thanks Mike. H^^ much appreciate your input on this. I have pretty much done the list above about a year ago (bench trim).. it just evolve to what I've posted above. but I'll try it again and see if I was going forward or backwards on that. The 2" CG seems way too nose heavy for my liking.. I would say min 2 3/16 - 2 1/4". The plane flys good as is at this point.. it was just the RWO. and it seems the speed did help. Alan watched one of my flights on Sunday, and his comment was too slow.. and that's with the 11x4 APC on a slightly slower 5.33 run. but the heavy APC does upsets the airframe in the corners tho, as why I like the 10"Tornado 3B prop, and the Xoar wood props. Sure would like to try the Bolly 10.5x4.25 if I could find one. :)
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Joe, just a thought:
Set the CG to Mike's suggested 2", then before you say "dang, that's too slow" and move it, move the handle spacing out, even if it's more than Mike's recommendation.
I don't put a lot of weight on handle spacing, because different folks want different handle spacings -- I know* that I prefer a far narrower spacing than most other people I know, and it's because of the way I'm set up, not my airplanes.
* Based on loaning out my planes, and flying other people's.
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Joe, just a thought:
Set the CG to Mike's suggested 2", then before you say "dang, that's too slow" and move it, move the handle spacing out, even if it's more than Mike's recommendation.
I don't put a lot of weight on handle spacing, because different folks want different handle spacings -- I know* that I prefer a far narrower spacing than most other people I know, and it's because of the way I'm set up, not my airplanes.
* Based on loaning out my planes, and flying other people's.
Hi Tim, I started out with CG at 2" , and it was damn scary to fly the precise 5' bottoms. especially the exit of the hourglass.. I then slowly change little by little to where it works for me.. but around 2 1/4- 5/16" is pretty much at the very edge of from good to what Mike have mentioned " jumpy' ! The plane performs great as is.. it is just the RWO. Every time I change a prop.. the CG change anyways. and yes, I weight everything I remove and replace including prop nuts etc. *Edit: forgot to mention the handle spacing is already at 4 1/8"
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I figured I oughta try to copy & paste the mysterious information I emailed to Joe. This was written by Mr. Ted Fancher, FYI. It seemed to me that Joe's setup might be improved by working on some of these suggestions, particularly items 1, 2, 3 & 4. Especially note the thoughts about the wingover! Thanks to Ted for putting this stuff in writting to help the rest of us. y1 Steve
"There are things you need to do to prepare for flying in high winds. Most important concept to remember is that stunt flying is ALL about energy management. Converting kinetic energy into potential and back. Energy management is critical when flying in windy conditions. Here's what works for me:
Setup:
1) Don't bother flying nose heavy models in high winds. There is no way around this: the further forward CG(Center of Gravity) from CL(Center of Lift), the larger the arm of force, the mode wind will push the model around. Make sure models have CG where designer intended them. If unsure where it it should be, balance the model so that CG is 6-12mm in front(can someone verify that it's in FRONT and not BEHIND, I'm always fuzzy about this) of CL.
2) Never trim in high winds. Make sure to trim the model when winds are less than 5km.
3) if you are using 3 blade prop, switch to larger diameter 2-blade prop with SQUARE tips.
4) increase launch RPM's to get .1-.2 faster lap times.
Flying maneuvers:
Takeoff:
Launch so that the wind is in the back of the model. The idea is have wind help the model accelerate(build up energy) on the downwind side(right side) of the circle. The goal is to get airborne just before you cross over from downwind to upwind side of the circle. The reason for doing it before crossing over is that you will need to establish gradual climb before you get to the up wind side. Once you're on the upwind side, the model will begin to slow down. slow = poor response to control inputs. If you are not established on the climb out, it will be difficult to change direction on the upwind side. As a general rule, the model will respond slower to control inputs on the upwind side of the circle.
Level flight:
There is not much to do here but to prepare for one of the most difficult maneuvers: wingover. To do that, you need to build up momentum. Start accelerating the model by walking backward in circle, keeping the model in font of you. The last lap before the wingover you should be walking backward as fast as possible without tripping over.
Wingover
This is the most difficult maneuver because the model is heavy(full of fuel) and has forward CG. Make soft entries into turns 1 and 3.The entry should be as if you are starting a round circle rather than a typical square entry. Another critical component is to enter directly upwind. You have to abandon the notion that you can steer the model in high winds. No amount of corrections will make the model fly straight wingover if you did not enter directly downwind. If you miss the turn and the model starts move sideways, accept the error and fly the rest of the maneuver in the direction the wind is blowing.
Inside and outside round loops, Inside square loop
Flying round loops directly downwind will cause the model to move faster and faster with every loop. This is called the "windup" and it may cause the model go so fast that it will fly into the ground. Key here is to avoid windup by biasing the center of loops to the left of the downwind for inside loops and to the right for the outsides. Amount of bias is directly proportional to how high the winds are. More wind, more bias. Start by flying insides 3m past direct downwind. If you get the amount of bias correct, the model will fly loops as if there is no wind! Oh yes, one critical detail: NEVER FLY above 45 degrees!!! think of 45 as "do not cross" line. If you do, the lines will go slack and the model will be at the mercy of Boreas, the God of the Wind!
Outside Squares
Same bias rules apply as with round loops. At the entry into the maneuver, the model will be going very fast. Turning down will make it go even faster. There is very little you can do so be prepared to turn hard and quick. There is one very good trick to lower the entry speed to somewhere manageable: do not start climb to enter outsides until you are on the downwind side of the circle. Speed loss due to the climb will offset the speed gain provided by the wind on the downwind side. The steeper the climb, the slower the entry will be. Don't make it too slow though: slow = lack of control.
Triangle
Bias just like you would with rounds. The first turn will be on the upwind side and the wind will make the model turn harder that usual so there is no need to make that hard first turn. Let wind help you. The less you turn, the more energy you will have for turn 3.
Horizontal round and square 8
DO NOT BIAS! DO NOT FLY ABOVE 45! These maneuvers should be directly down wind. Be prepared for the model to slow down significantly at the top and adjust your timing accordingly. Most pilots develop a rhythm for squared 8's: evenly spaced turn, turn, turn. That rhythm is your enemy in high winds! Fly by watching position of the model instead.
Vertical 8
This seems to be the most difficult maneuver for most pilots because most pilots fly large inside loop which places the outside loop past 90 degrees. Past 90, there is not just the wind slowing it down, the wind s actually pushes it DOWN towards you! The key here is to keep inside loop tight below 45, directly downwind. Remember the wind up issue when flying round loops directly down wind? Well, here we NEED that wind up to build energy for the outside top loop! Another key element here is to keep line tension up. One way to do it is to shorten the lines. I typically fly with my hand almost extended. When flying the outside loop, I bring the handle closer to my chest and begin to I will begin to kneel on one knee. What this does is decrease the radius of the circle the model flies which increases line tension. Stand back up and move the hand to regular position for the down side.
Hourglass
Unlike other maneuvers that have just one or two tricks to keep flying, hourglass needs 5 tricks!
1) Build up energy by walking backwards like just like you did for the wingover. slowly build up the speed, so that you are walking the fastest during the last 1/4 lap before turn 1.
2) make a shallow turn up. Since turn 1 takes place on the upwind side, the wind will make the turn steeper than usual so you need to account for it.
3) The wind will push the model after turn 1 and will help the model speed up. At this point you need to build your energy for turns 2 and 3. Extend you arm completely if possible
4) As you approach turn 2, the lines will begin to slack and you will not be able to make that turn unless you keep the tension up! Start contracting your arm and kneel. Shortening the flying radius transfers built up energy into model speed and line tension.
5) Turns 2 and 3 should be done very quickly one after the other. Turn 2 forces the model to turn hard into the wind which kills most of the energy. The more you stay up there the slower the model will get.
After turn 3, the model will be traveling down plus be pushed by the wind. This will translate into a lot of speed. Turn 4 will come very quick and suddenly. You need to keel the energy. Stand back up and extend your arm. If the wind is really strong, I go as far as make a step forward..
Overhead 8
Make a gradual entry from level flight. The key here is not to loose energy on the way up. Spend as little time flying into the wind by keeping the loops tight. Most pilots fly big overhead loops. DO NOT DESCEND BELOW 45!!! Large loops mean very long flight into the wind! Another trick is to contract the arm/kneel when flying into the wind and to release/stand on the downwind side of the loops. It is also VERY IMPORTANT that you fly the maneuver DIRECTLY overhead. This is again has to do with how much time you spend flying into the wind.
Clover
There is little you can do to keep the tension. All you have is make sure you don't cross 90 degrees on loops 1 and 3. Contract arm/kneel as needed to keep line tension, stand/release when wind is pushing the model to store the energy. On the final climb out, the model has lost the most energy, it's climbing AND flying into the wind. This is where models get lost. As soon as you cross 90 degrees, the maneuver is over and you can start the turn downwind.
Landing
Try to land on the down wind side as the wind as this will be where line tension is the highest.This is important since the model will start moving INTO the wind and will try to lift off. you need line tension to keep the model down on the ground. I usually aim for 5m before directly downwind as my landing point."
Steve,
Not sure where you got this material but it isn't what is in the Fly Like a Champion articles. It's similar in format but contains items (such as the takeoff position in the wind) with which I disagree. I also noticed dimensions in metric figures which I've never used to the best of my recollection.
It's not bad at all but I'd prefer that my original stuff be quoted so I don't have to debate things I haven't espoused myself.
Shareen mentioned that she keyed the original stuff for me some years ago. I'll look through my stack of discs to see if that's so and if it is I'll repost that. It won't, however, contain the graphics that were in the magazine.
No big deal! I'm not complaining, just wanted the facts to be straight.
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I don't want to argue with Ted's writings but I thought I might add a little input here.
If you decide to take off with the wind on the back of the model be prepared that any up elevator before model is at speed will tip it over and eat the prop. I have seen this time and time and time and time and time again at all levels of flying from the nats top 20 day down to the weekend sport session. So many carbon props, many that can't be duplicated, torn up during this type of launch. Wind from behind the model hinders the surfaces effectiveness. They actually work opposite of what they are supposed to do.
What works for me on high wind days is to take off dead down wind or just a few feet past dead down wind. Prior to release level the elevator and keep the model level as it comes up to speed. The wind will help it lift off ground faster than normal but you will have control over it with a simple step back if needed. Or you can feed a little down into it and keep it on the ground until it is up to speed and then lift off. You have to be off of the ground prior top 1/4 lap anyway so you can be up before the wind is directly into the models face. I was once told a very long time ago these "These things were built to fly so get it in air, QUICKLY!"
Doug,
I agree 100%. Whoever wrote what Steve posted may have used my articles as a resource for some of what he wrote but the writing and quite a bit of the theory/practice is somewhat in conflict with my articles.
Ted
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Thanks again Steve. H^^ This is a much clearer version then the emailed one.
Good point! I've seen that happen to others, and has happened to me as well.
Thanks Mike. H^^ much appreciate your input on this. I have pretty much done the list above about a year ago (bench trim).. it just evolve to what I've posted above. but I'll try it again and see if I was going forward or backwards on that. The 2" CG seems way too nose heavy for my liking.. I would say min 2 3/16 - 2 1/4". The plane flys good as is at this point.. it was just the RWO. and it seems the speed did help. Alan watched one of my flights on Sunday, and his comment was too slow.. and that's with the 11x4 APC on a slightly slower 5.33 run. but the heavy APC does upsets the airframe in the corners tho, as why I like the 10"Tornado 3B prop, and the Xoar wood props. Sure would like to try the Bolly 10.5x4.25 if I could find one. :)
Joe, Please check out my notes to Doug and Steve. If you read my articles (I know the scans are tough) you'll see the content is significantly different.
Ted
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Ted, all I did was run it through SpellCheck...and was surprised to find some errors. I didn't notice the mealy meters! While I don't recall where I got it, it must have been online someplace, possibly the Australian stunt website, or maybe an English one. It is a puzzler. Looks like somebody (else) changed your article a little. I will edit your name out of the post and off the file!
Opinions seem to vary on the launching position...at NW Regionals, I let Keith Varley (my pit guy) influence me and almost lost my airplane. My ideal would be to launch just short of straight downwind about 15' or so...wish I had done that. After, I realized that Keith gets away with it because of his LH prop/ePower. Even if I was to have his power system, I still wouldn't do that again! Scary!!! H^^ Steve
Edit: I went back to the original file and didn't see that it was attributed to Ted at all! I'm so sorry! I was looking for the article Ted refers to in his post and apparently leaped to that conclusion...wrong!
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I don't want to hijack this thread, but it's been a long time since hearing from you Mike. Where are you now and how are you doing?
Hi Paul and Randy,
I'm doing pretty good for the most part. I am back in Minnesota freezing my @#$ off and had to purchase a new snow blower to get out of the house (LOL). After Patrica passed, I moved back to be around the kids and grand kids and watch them grow up. I do really miss all my old friends and enjoyed their friendship's.
I met a wonderful lady, Lois (retired Air Force). We hit it off from the first and enjoy eachothers company and share many interests. She even puts up with me making a big mess on the kitchen table building models (now that's way cool).
Later,
Mikey
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Thanks again Steve. H^^ This is a much clearer version then the emailed one.
Good point! I've seen that happen to others, and has happened to me as well.
Thanks Mike. H^^ much appreciate your input on this. I have pretty much done the list above about a year ago (bench trim).. it just evolve to what I've posted above. but I'll try it again and see if I was going forward or backwards on that. The 2" CG seems way too nose heavy for my liking.. I would say min 2 3/16 - 2 1/4". The plane flys good as is at this point.. it was just the RWO. and it seems the speed did help. Alan watched one of my flights on Sunday, and his comment was too slow.. and that's with the 11x4 APC on a slightly slower 5.33 run. but the heavy APC does upsets the airframe in the corners tho, as why I like the 10"Tornado 3B prop, and the Xoar wood props. Sure would like to try the Bolly 10.5x4.25 if I could find one. :)
Hi Joe,
The 2" CG is the best place to start then, and trim to fit your needs is the best. 5.33 lap times are still a little slow so cut 1' or 2' foot of line length to get the laps times to 5.0 or 5.1. Contact Steve Wilks "Elimnator Products" to purchase a 10.5 X 4.25 undercamber C/F prop.
Later,
Mikey
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Ted, all I did was run it through SpellCheck...and was surprised to find some errors. I didn't notice the mealy meters! While I don't recall where I got it, it must have been online someplace, possibly the Australian stunt website, or maybe an English one. It is a puzzler. Looks like somebody (else) changed your article a little. I will edit your name out of the post and off the file!
Edit: I went back to the original file and didn't see that it was attributed to Ted at all! I'm so sorry! I was looking for the article Ted refers to in his post and apparently leaped to that conclusion...wrong!
Hi Steve, I just did a search and found my old post.. "Techniques for flying in the wind.." looks like it's from Stephen Yampolsky. reply #11 http://stunthanger.com/smf/index.php?topic=16949.msg155855;topicseen#msg155855
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Hi Joe,
The 2" CG is the best place to start then, and trim to fit your needs is the best. 5.33 lap times are still a little slow so cut 1' or 2' foot of line length to get the laps times to 5.0 or 5.1. Contact Steve Wilks "Elimnator Products" to purchase a 10.5 X 4.25 undercamber C/F prop.
Later,
Mikey
I'll try a little more speed (5.15 lap time) and see how that goes, before cutting the lines. I asummed the 10.5x4.25 is a 2-blade?
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Hi Steve, I just did a search and found my old post.. "Techniques for flying in the wind.." looks like it's from Stephen Yampolsky. reply #11 http://stunthanger.com/smf/index.php?topic=16949.msg155855;topicseen#msg155855
Joe and Steve,
really, no worries at all. It's just a matter of attribution with respect to a handful of things on which Steve and I differ.
I got to know Steve pretty well judging at the last Nats and enjoyed his company and was pleased that, during the warm-up/training flight talkarounds, we tended to see pretty much the same things; tending to concentrate on maneuver shapes rather than individual aspects--believing that if the shapes (and sizes) were right the rest of the stuff pretty much falls in line. We did have some "spirited" discussions about how to assess the point deductions for what we were seeing alike but, to his credit, he continued to assess the tricks his way consistently from the start to the end of the contest...which is the only fair way to do it. I've no idea whether my input affected his later judging efforts. I was, of course, right and Steve wrong but I'll eventually get him straightened out. >:D >:D >:D KIDDDINGG!
Ted
Edited to repair a name error.
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I just uploaded a few videos from last week's sessions. Here are a few short clips on corners (in slow motion) from my first flight last Sunday.. 5.25/lap with the Tornado 10x4 3-blade prop. Even though the camera was aimed off to one side, you could at least see the last corner.. :)
Inside Square Maneuver (slow motion):
http://youtu.be/ZFNenv0OulM
Inside Square Maneuver (normal speed):
http://youtu.be/PoSOGd3fMe4
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The second video shows the plane flying a little faster to this old mans eye balls. The first video the plane is much too slow. Each plane has a speed it likes to fly at. Control lap times with line length.
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The second video shows the plane flying a little faster to this old mans eye balls. The first video the plane is much too slow. Each plane has a speed it likes to fly at. Control lap times with line length.
Hi John, both of the video are the same.. the first one is in slow motion for to see the turn closer. and the second one is the original speed it was flown at.
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Love that slow motion! y1 y1
Jerry