c.g. vs Throws
08-25-2006 | 03:05 PM
#1
Thread Starter
c.g. vs Throws
This may be a silly question
How do you tell whether your c.g. is in the right place or if you need more elevator throw?
I don't know whether to increase my throws or move the c.g. back. How do you set yours up?
How do you tell whether your c.g. is in the right place or if you need more elevator throw?
I don't know whether to increase my throws or move the c.g. back. How do you set yours up?
08-25-2006 | 04:19 PM
#2
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From: Fort Mohave,
AZ
RE: c.g. vs Throws
siclick33.... There can never be no silly questions......
I maybe wrong... But I try to set my CG, at first per man. inbetween low/hi
then set so as the plane will fly inverted hands off.. I always use dual rates...
Low rate.. adjustable per?? But it starts off per man... Hi rate is everything I
can get... As I said, not sure if it's how it should be done, just how I do it...
I maybe wrong... But I try to set my CG, at first per man. inbetween low/hi
then set so as the plane will fly inverted hands off.. I always use dual rates...
Low rate.. adjustable per?? But it starts off per man... Hi rate is everything I
can get... As I said, not sure if it's how it should be done, just how I do it...
08-25-2006 | 04:54 PM
#3
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RE: c.g. vs Throws
I dont like to make them any more tail heavy than is absolutely necessary. Lots of throw with strong servos will achieve about as much as an excessively aft CG. I agree with raideron. Trim the plane so that it flies hands off level upright and for inverted you put the plane in an inverted 45 degree climb and release the elevator at about 1/2 throttle the plane should VERY slowly fade downward. If the plane is flying hands off level inverted then you are pushing your luck with tailheavy. A tailheavy plane is a little easier to hover and it does some things a little easier but the plane will not "fly" as well and it will be way less stable, especially when you slow it down to land.
Again you want to acheive
1 hands off flat upright level flight at about 1/2 throttle
2 inverted in a 45 degree climb when you let off the elevator the plane just sightly fades downward with just a breath of down elevator to sustain level inverted flight.
Once you get there THEN increase the high rate elevator throw as much as is necessary to perform the most demanding 3D move in your arsenal. Usually a waterfall, wall and parachute would be the most demanding for big elevator response.
Again you want to acheive
1 hands off flat upright level flight at about 1/2 throttle
2 inverted in a 45 degree climb when you let off the elevator the plane just sightly fades downward with just a breath of down elevator to sustain level inverted flight.
Once you get there THEN increase the high rate elevator throw as much as is necessary to perform the most demanding 3D move in your arsenal. Usually a waterfall, wall and parachute would be the most demanding for big elevator response.
08-25-2006 | 04:55 PM
#4
My Feedback: (3)
RE: c.g. vs Throws
ORIGINAL: MikeEast
I dont like to make them any more tail heavy than is absolutely necessary. Lots of throw with strong servos will achieve about as much as an excessively aft CG. I agree with raideron. Trim the plane so that it flies hands off level upright and for inverted you put the plane in an inverted 45 degree climb and release the elevator at about 1/2 throttle the plane should VERY slowly fade downward. If the plane is flying hands off level inverted then you are pushing your luck with tailheavy. A tailheavy plane is a little easier to hover and it does some things a little easier but the plane will not "fly" as well and it will be way less stable, especially when you slow it down to land.
Again you want to acheive
1 hands off flat upright level flight at about 1/2 throttle
2 inverted in a 45 degree climb when you let off the elevator the plane just sightly fades downward with just a breath of down elevator to sustain level inverted flight.
Once you get there THEN increase the high rate elevator throw as much as is necessary to perform the most demanding 3D move in your arsenal. Usually a waterfall, wall and parachute would be the most demanding for big elevator response.
I dont like to make them any more tail heavy than is absolutely necessary. Lots of throw with strong servos will achieve about as much as an excessively aft CG. I agree with raideron. Trim the plane so that it flies hands off level upright and for inverted you put the plane in an inverted 45 degree climb and release the elevator at about 1/2 throttle the plane should VERY slowly fade downward. If the plane is flying hands off level inverted then you are pushing your luck with tailheavy. A tailheavy plane is a little easier to hover and it does some things a little easier but the plane will not "fly" as well and it will be way less stable, especially when you slow it down to land.
Again you want to acheive
1 hands off flat upright level flight at about 1/2 throttle
2 inverted in a 45 degree climb when you let off the elevator the plane just sightly fades downward with just a breath of down elevator to sustain level inverted flight.
Once you get there THEN increase the high rate elevator throw as much as is necessary to perform the most demanding 3D move in your arsenal. Usually a waterfall, wall and parachute would be the most demanding for big elevator response.
08-27-2006 | 06:53 AM
#5
Thread Starter
RE: c.g. vs Throws
Thanks guys.
My main problem is that spins are not as violent as I would like and flips are more like little loops (although the latter may be pilot error). I'll try the tests mentioned above and see what happens.
My main problem is that spins are not as violent as I would like and flips are more like little loops (although the latter may be pilot error). I'll try the tests mentioned above and see what happens.
08-27-2006 | 12:21 PM
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From: Lewiston, ID
RE: c.g. vs Throws
For the flips, make sure you're getting out of the throttle during the flip. You set it in motion with a blip of power and, for a forward flip, full down. It should do the rotation on inertia. this will really tighten it up.
08-27-2006 | 01:28 PM
#7
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RE: c.g. vs Throws
ORIGINAL: AeroDave
For the flips, make sure you're getting out of the throttle during the flip. You set it in motion with a blip of power and, for a forward flip, full down. It should do the rotation on inertia. this will really tighten it up.
For the flips, make sure you're getting out of the throttle during the flip. You set it in motion with a blip of power and, for a forward flip, full down. It should do the rotation on inertia. this will really tighten it up.
You bet. Full power over the top and as soon as it comes over the top power off, then back on over the top. Sometimes you will hit it just right and it will wind up and flip or "waterfall" REALLY fast with full power once you get it going. Real cool and once you figure out the trick for your plane you will be able to get it to do this on demand. [8D]
08-27-2006 | 03:53 PM
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From: Buckingham, UNITED KINGDOM
RE: c.g. vs Throws
Some like to fly inverted without any down in, i do not. Inverted flight with a highly aerobatic plane should just need a hint of down elevator. You will notice though if the aircraft isnt as responsive on rates as youd like as you shift the CoG back it gets more and more responsive and generally does knife edge, harriers and especially flat spins far better with a slightly rearward CoG. HOwever, I have never found the need to go rearward beyond the point where the model starts climbing inverted hands-off! Landings also then get interesting as they usually require down elevator, and flare is a return to nuetral and maybe slight up...very unnatural...
08-27-2006 | 04:27 PM
#9
My Feedback: (3)
RE: c.g. vs Throws
ORIGINAL: amjflyer
Some like to fly inverted without any down in, i do not. Inverted flight with a highly aerobatic plane should just need a hint of down elevator. You will notice though if the aircraft isnt as responsive on rates as youd like as you shift the CoG back it gets more and more responsive and generally does knife edge, harriers and especially flat spins far better with a slightly rearward CoG. HOwever, I have never found the need to go rearward beyond the point where the model starts climbing inverted hands-off! Landings also then get interesting as they usually require down elevator, and flare is a return to nuetral and maybe slight up...very unnatural...
Some like to fly inverted without any down in, i do not. Inverted flight with a highly aerobatic plane should just need a hint of down elevator. You will notice though if the aircraft isnt as responsive on rates as youd like as you shift the CoG back it gets more and more responsive and generally does knife edge, harriers and especially flat spins far better with a slightly rearward CoG. HOwever, I have never found the need to go rearward beyond the point where the model starts climbing inverted hands-off! Landings also then get interesting as they usually require down elevator, and flare is a return to nuetral and maybe slight up...very unnatural...
