Espritmodel.com Telemetry Radio
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Old Dec 21, 2012, 05:32 AM
This thing runs real nice...
Nam Lemmi's Avatar
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Originally Posted by Jovanx View Post
This plane is definitely not a hotliner, and it's quite the handful to try to make it fly level at max throttle. At that speed, the elevator is over sensitive and that contributes to the "wing flapping" that many people see. Max throttle is just for going up at a steep angle.
Yeah I think that's what happened on my second flight last week. And being down low I had no time to recover. Lesson learnt
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Old Dec 21, 2012, 05:41 AM
This thing runs real nice...
Nam Lemmi's Avatar
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Originally Posted by campbellj View Post
I was actually looking at radians today to buy. I'm really considering it as of now, they seem to be just a different animal all together so to me it wouldn't be like having 2 of "almost" the same plane.
Well I bought the Radian Pro last week and the Radian today. Only got 2 flights on the Pro before I crashed it and have only had time for 1 maiden on the Radian today.

I'm glad I bought both. I love the simplicity and easy, relaxing nature of the original Radian. Can see it being my "go to" plane when conditions are calm and I think the Pro will be for when the wind picks up. But if I had to choose one I think it would be the original Radian.

I'm no expert so this is just my point of view as a glider newby.
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Old Dec 21, 2012, 05:51 AM
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Originally Posted by Nam Lemmi View Post
Well I bought the Radian Pro last week and the Radian today. Only got 2 flights on the Pro before I crashed it and have only had time for 1 maiden on the Radian today.

I'm glad I bought both. I love the simplicity and easy, relaxing nature of the original Radian. Can see it being my "go to" plane when conditions are calm and I think the Pro will be for when the wind picks up. But if I had to choose one I think it would be the original Radian.

I'm no expert so this is just my point of view as a glider newby.
I hope they each give you many hours of enjoyment as you grow into the RP
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Old Dec 21, 2012, 07:39 AM
This thing runs real nice...
Nam Lemmi's Avatar
Joined Jun 2012
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Originally Posted by coreman View Post
I hope they each give you many hours of enjoyment as you grow into the RP
Cheers Coreman I can see many pleasant hours ahead.

Weather forecast for tomorrow is easterly winds about 10-15 knots so I'm going to stick the #16 key chain camera on and hopefully take some nice slope soaring video.
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Old Dec 21, 2012, 10:55 AM
Tossing planes into the snow
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Originally Posted by coreman View Post
lateral balance makes more of a difference than people realize and the problem with "trimming it out with aileron" is that the fix is only good at one speed. go faster and the trim is more effective and it goes beyond what is needed and slow down and it isn't enough. If the surfaces are neutral, the speed won't change the trim
Thank you for that explanation, coreman. It totally explains why I couldn't get my RP to fly straight. No amount of aileron or rudder trim ever worked for long. Then one day, months later, I clued into the fact that one wing was 4.5 grams heavier than the other. A quarter taped to the underside of the wing at just the right spot made all the difference.
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Old Dec 21, 2012, 12:06 PM
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Thank you for that explanation, coreman. It totally explains why I couldn't get my RP to fly straight. No amount of aileron or rudder trim ever worked for long. Then one day, months later, I clued into the fact that one wing was 4.5 grams heavier than the other. A quarter taped to the underside of the wing at just the right spot made all the difference.
So should I be able to practically balance the plane on the landing skids? I was messing with mine last night after getting it all back together and noticed it always wants to fall to the left wing, so I know the left side is heavier. I know actually getting it to balance on the skids would be hard, but it wouldn't be hard to tell when it's close.

Also as far as CG is 77mm from the leading edge what you all use or the 70mm that the manual says? Seems at 77mm on my fingertips I almost have to get the battery out of its hole to balance. I'm probably gonna rig up something tonight to balance it properly without my fingers. Also the CG should be checked with the prop folded in right?
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Old Dec 21, 2012, 12:11 PM
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Originally Posted by campbellj View Post
So should I be able to practically balance the plane on the landing skids? I was messing with mine last night after getting it all back together and noticed it always wants to fall to the left wing, so I know the left side is heavier. I know actually getting it to balance on the skids would be hard, but it wouldn't be hard to tell when it's close.

Also as far as CG is 77mm from the leading edge what you all use or the 70mm that the manual says? Seems at 77mm on my fingertips I almost have to get the battery out of its hole to balance. I'm probably gonna rig up something tonight to balance it properly without my fingers. Also the CG should be checked with the prop folded in right?
To get from 70 to 77 you should have to move the battery back, not forward. Not sure how you are measuring this, but 77mm is about where the servo wires come out of the wings.
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Old Dec 21, 2012, 12:50 PM
Tossing planes into the snow
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Originally Posted by campbellj View Post
So should I be able to practically balance the plane on the landing skids? I was messing with mine last night after getting it all back together and noticed it always wants to fall to the left wing, so I know the left side is heavier. I know actually getting it to balance on the skids would be hard, but it wouldn't be hard to tell when it's close.
Jumpy is right...you should have to have the battery all the way back to get it to 77mm. Mine always wanted to fall onto the left wing as well whenever I sat it on a table. I'm embarrassed to say, it took me a lot longer than it took you to clue into that fact. I just laid a quarter on the right wing and held it level and watched which way it fell, and then adjusted the position of the quarter. Once it gets to the point where it's hard to tell which side it favors, you are probably there.

When you put the arrow shaft in the fuselage, did you first remove the fiberglass spar, or is it still in there. With all the mods you did, how much weight do you think you added to the tail? Maybe that is why you have to push the battery forward to get 77.
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Old Dec 21, 2012, 03:12 PM
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United States, MA, Southbridge
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Originally Posted by campbellj View Post
So should I be able to practically balance the plane on the landing skids? I was messing with mine last night after getting it all back together and noticed it always wants to fall to the left wing, so I know the left side is heavier. I know actually getting it to balance on the skids would be hard, but it wouldn't be hard to tell when it's close.

Also as far as CG is 77mm from the leading edge what you all use or the 70mm that the manual says? Seems at 77mm on my fingertips I almost have to get the battery out of its hole to balance. I'm probably gonna rig up something tonight to balance it properly without my fingers. Also the CG should be checked with the prop folded in right?
I balance it laterally upside down so the tip droop keeps it centered. otherwise it just falls over too fast. I'm balanced somewhere in the 75-85mm range for CG. A finish nail or brad pushed into a wing tip will correct lateral balance pretty easily. those slip on pencil erasers into pencils drilled into a wood base works well for CG

Good pictures of it here
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Old Dec 21, 2012, 03:26 PM
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Originally Posted by JumpySticks View Post
To get from 70 to 77 you should have to move the battery back, not forward. Not sure how you are measuring this, but 77mm is about where the servo wires come out of the wings.
I measured with a metric ruler, from the leading edge at the fuse. But I totally think I'm measuring from the wrong spot because my t-28 always measured tail heavy. I got fed up with trying to make it right and just shoved the battery as far forward as it would go and put it in the air. Flew great!

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Originally Posted by Jovanx View Post
Jumpy is right...you should have to have the battery all the way back to get it to 77mm. Mine always wanted to fall onto the left wing as well whenever I sat it on a table. I'm embarrassed to say, it took me a lot longer than it took you to clue into that fact. I just laid a quarter on the right wing and held it level and watched which way it fell, and then adjusted the position of the quarter. Once it gets to the point where it's hard to tell which side it favors, you are probably there.

When you put the arrow shaft in the fuselage, did you first remove the fiberglass spar, or is it still in there. With all the mods you did, how much weight do you think you added to the tail? Maybe that is why you have to push the battery forward to get 77.
I took out the fiberglass spar. The only weight I added was a carbon rod in the vertical stab and any weight the arrow shaft and gorilla glue could have added.
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Old Dec 21, 2012, 03:29 PM
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Originally Posted by coreman View Post
I balance it laterally upside down so the tip droop keeps it centered. otherwise it just falls over too fast. I'm balanced somewhere in the 75-85mm range for CG. A finish nail or brad pushed into a wing tip will correct lateral balance pretty easily. those slip on pencil erasers into pencils drilled into a wood base works well for CG

Good pictures of it here
Should I measure it upside down? I measured my t-28 upside down but figured this one could be right side up because the wings are up top. Maybe that's my problem.
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Old Dec 21, 2012, 03:38 PM
Tossing planes into the snow
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I took out the fiberglass spar. The only weight I added was a carbon rod in the vertical stab and any weight the arrow shaft and gorilla glue could have added.
Then you only added a few grams and that is not the problem. My arrow shaft only weighed 2 grams more than the spar that was removed. Also I use the 2 pencils in a block of wood method to measure CG and just sharpen the existing erasers that are on the pencils. Doing it upside down works ok on this plane.

If for whatever reason you need to move the battery ahead, an easy way is to simply switch the locations of the ESC and the battery. That's what I did when I first got the plane and wanted to get it to 70 as per the manual. Now the battery is back in the battery compartment and it is pretty close to 77. It would be a good option for somebody using a tail-cam.
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Old Dec 21, 2012, 03:47 PM
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What will give the plane a more relaxing, easier to control flight? 70 or 77? I would think 70 having a little more weight up front.
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Old Dec 21, 2012, 03:56 PM
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Originally Posted by campbellj View Post
I measured with a metric ruler, from the leading edge at the fuse. But I totally think I'm measuring from the wrong spot because my t-28 always measured tail heavy. I got fed up with trying to make it right and just shoved the battery as far forward as it would go and put it in the air. Flew great!
Well, a nose heavy plane will fly good. a tail heavy plane will be more sensitive (extreme cases are called squirrelly) to stab movements and will indicate lift/thermals better. You will need less throw the further back you move the CG

Another thing that people don't think about is that you need to move your control rods on the horns/servo arms when you reduce your throws and not just dial it back in the radio. The full travel of the servo has a number of discrete steps (256, 512 or 1024 depending on the radio - this is a function of the D to A converter used in the electronics) and if you set your rates/travel adjustment to 50%, you use half of them. This means that as you move the stick the control jumps a step at a time to move. If you are set up with miniscule travel ranges (extreme case example here) such as 10% and you have a 256 step radio, you only have 25 positions for the control surface and this makes errors for the slop in your linkage and the centering of your servo much worse over the range of the movement (amplifies the error) When setting up a 3D plane, it is recommended that you set your radio to the maximum travel, 150% on some, and then adjust the hole on the servo arm and control horn to get the movement desired so even if you only have 10% of the possible motion, you get (in the example above) 256 discrete positions of the control surface and much more precise control. This can also sometimes be seen when using trims and one click is wrong in a direction but a click the other way is in the other direction because (in the example above) your 25 step surface travels 10 steps for the click versus one by one in the 256 (150%) step case. This is also why more expensive radios tend to have higher resolution (more bits in the D to A converter)
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Old Dec 21, 2012, 04:00 PM
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Should I measure it upside down? I measured my t-28 upside down but figured this one could be right side up because the wings are up top. Maybe that's my problem.
Whichever way you can get it to balance easiest. With the raised wingtips or dihedral I find it tends to balance easier upside down. Do it both ways while you try to figure it out and see which balances easier
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