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  #1  
Old 12-12-2006, 05:12 AM
T_SQUARE T_SQUARE is offline
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RC Plane/ Model Rocket Dopers: Can a Rookie fly something like this?

I got one of these the other day. I saw some guys flying RC gliders and it looked like fun. Yeah, kind of an impusle buy.

I don't have any experience with RC planes, but I'm pretty good at building stuff, so I'm confident I can put it together fine. Also, I had model rockets as a kid, so I know how the launch thing works. But the instructions don't really tell you what to do after lift off.

It has a "V" tail, so I think you have one stick (don't have the remote yet). I'm guessing foward is down back is up, and right and left are prettty obvious. What are my chances of being able to land safely, do you suppose? If the glider was trimmed well, could I not pilot it at all, and just kind of let gravity do her thing after launch? The whole thing weighs less than an pound, so she's not a sturdy as I'd hoped, I think the ground might be unforgiving. Did I bite off more than I can chew here?

I'm a pretty decent combat pilot... on the old PS2 if that makes any difference.
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  #2  
Old 12-12-2006, 06:03 AM
Ale Ale is offline
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Join Date: May 2003
Quote:
Originally Posted by T_SQUARE
I got one of these the other day. I saw some guys flying RC gliders and it looked like fun. Yeah, kind of an impusle buy.

I don't have any experience with RC planes, but I'm pretty good at building stuff, so I'm confident I can put it together fine. Also, I had model rockets as a kid, so I know how the launch thing works. But the instructions don't really tell you what to do after lift off.

It has a "V" tail, so I think you have one stick (don't have the remote yet). I'm guessing foward is down back is up, and right and left are prettty obvious. What are my chances of being able to land safely, do you suppose? If the glider was trimmed well, could I not pilot it at all, and just kind of let gravity do her thing after launch? The whole thing weighs less than an pound, so she's not a sturdy as I'd hoped, I think the ground might be unforgiving. Did I bite off more than I can chew here?

I'm a pretty decent combat pilot... on the old PS2 if that makes any difference.
By the shape of that plane it should fly itself without problems provided you trim it correctly. So youīd lit up the fuse, toss it towards a point in the ground around 60 feet ahead of you (never, ever throw a model pointing up!) and let it go on itīs own merry way until the rocket kicks in; at that point it will probably get going at a good clip so you may want to give little corrections with the rudder (left or right stick), move it slowly to one side until you notice the effect. Donīt try to stir it too tight and keep in mind that the climbing will end when the rocket is exhausted, donīt try to gain more altitude after that.

For trimming the model you should build it as per the plan, appart from building the thing straight the most important thing is to correctly balance the plane; the plan will indicate the Center of Gravity (CG) position with a black and white circle divided in quarters. For that you hold the model with a finger under each wing at the CG position and see if it stays level or not. Youīll probably be instructed to place a rocket engine in place while balancing the model, you can move the battery and receiver forward or backwards to get the model to lay level, if thatīs not enough youīll need ballast, lead or bismuth if you want something more ecologicaly friendly.

Once the model is balanced check for warps on the wings or any other deviations, if all is reasonably straight take it out on a calm wind day and make a test glide over a grass surface (the taller the better!), toss it as I said at the begining, aim at some point on the ground 60ī ahead of you with a quick but gentle push; the idea here is to get it to flight speed, it can be tricky for someone that never launched a model to get the correct launch speed, so you may want to hold the model from the fuselage above your head and run in a straight line into the wind to get a feeling of how fast it should move to get enough lift. The model is quite light and has a large wing area so it doesnīt need a great speed to stay up.
Now, before you actually toss it make sure that the RC is on and that the flight surfaces work correctly (pull the stick and the elevons should go up, push it and they go down, right stick and the left elevon goes up and the right goes down and vice-versa). This is actually a safeward measure since you shouldnīt give any input commands when glide testing the plane, the idea is that you want to trim it to fly on itīs own.
OK, flight time!, toss it (at last) and see how it goes, if it keeps going straight down you either tossed it too slow or the model is nose heavy, if it pitches up and stalls you threw it too hard or itīs still tail heavy. You can make small adjustments to the CG position by moving the RX and battery around a little, or using ballast, but donīt move it too much from the position in the plan.

f the model still wonīt fly straight youīll have to use the trim pots in your transmitter, this are small sliders on the side of the stick that fix the rest position of the servos, so if you move the elevator trim pot back the elevator will always be deflected up (pitch up) even if the stick is centered. So if your model keeps diving even though the CG looks correct do that to correct the trajectory. If the model stalls put some down trim, but not much; a stalling plane kept on itīs tracks by down elevator is a disaster looking for a place to happen, itīs better to correct this with ballast.
You may also use the rudder trim pot to compensate for small warps on the structire and keep the model going straight.

Well, I should be working so Iīll end here by now; but yes, a complete noob can fly a model like that as long as it is properly trimmed and he doesnīt muck too much with the controls.
The plane should be able to fly on itīs own and in the begining you can simply point it here and there or go around in big circles.
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  #3  
Old 12-12-2006, 07:14 AM
UncleRojelio UncleRojelio is offline
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Join Date: Nov 2004
Location: ATX
Posts: 4,980
Quote:
Originally Posted by Ale
So youīd lit up the fuse, toss it towards a point in the ground around 60 feet ahead of you (never, ever throw a model pointing up!) and let it go on itīs own merry way until the rocket kicks in; at that point it will probably get going at a good clip so you may want to give little corrections with the rudder (left or right stick), move it slowly to one side until you notice the effect. Donīt try to stir it too tight and keep in mind that the climbing will end when the rocket is exhausted, donīt try to gain more altitude after that.
That is not how it is launched. You'll do the standard rocket launch setup with a launch pad, launch rod and controller. When the plane reaches apogee it will settle over and begin to fly. You can steer it if you want but otherwise, if properly trimmed, it will land all by itself.
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Old 12-12-2006, 07:53 AM
Ale Ale is offline
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Join Date: May 2003
Quote:
Originally Posted by UncleRojelio
That is not how it is launched. You'll do the standard rocket launch setup with a launch pad, launch rod and controller. When the plane reaches apogee it will settle over and begin to fly. You can steer it if you want but otherwise, if properly trimmed, it will land all by itself.
It launches vertically?
The knowledge I have of rocket powered models doesnīt cover RC planes but free flight one, which are hand launched on level flight, either with the rocket already burned or just before the wick starts ignition.
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  #5  
Old 12-12-2006, 08:23 AM
UncleRojelio UncleRojelio is offline
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Join Date: Nov 2004
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Quote:
Originally Posted by Ale
It launches vertically?
The knowledge I have of rocket powered models doesnīt cover RC planes but free flight one, which are hand launched on level flight, either with the rocket already burned or just before the wick starts ignition.
The rocket motors for these are electrically ignited. They are launched off a pad on the ground. The launch rod is usually at some angle off of vertical. Here is a (poor) YouTube video.
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  #6  
Old 12-12-2006, 08:43 AM
brewha brewha is offline
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Join Date: Apr 2001
Yeah, that plane should be easy to fly if it is setup correctly, balanced, and trimmed out. Without any previous RC experience, it will be difficult to get the plane ready to fly on your own. The first flight of any plane is always a handful even for experienced pilots.

I strongly recommend that you find a flying field and talk to the members. Most R/Cers are very helpful.

If you don't want to do that, at least bring a camera so when can see the wreckage.
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