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Old Jan 21, 2015, 02:39 PM
Badger
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Joined Jul 2008
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Theres no rudder - just elevons - and throws don't need to be large especially on aileron.
You're a brave guy if you dont have at least 20% expo on roll.
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Old Jan 21, 2015, 07:12 PM
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Australia, VIC, Melbourne
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I would say that I have about 8mm (from centre, each way) in the Pitch (Up/down), and maybe 5mm (from centre, each way) in Roll.
I don't use Expo but I do have Dual Rates set up. High Rate is probably about 8mm for Roll then, and that is just to give me "Super Rocket Rolls"!! Just for fun. I have flown around with that on, but it is not advised at all !!
High Rate Pitch is probably 10mm approx. This can be handy at hand launch time, as the Radjet takes a BIT of time to get speed up. So I take off with Pitch in High Rate mode, and often do leave that on all flight.

But in that High Rate Pitch state, you can then use excessive "elevator" and cause an Accelerated Stall - which is where you can Pitch the planes attitude TOO much, too quick, and thus the Angle Of Attack of the Wing to the airflow is too great and thus airflow 'de-laminates' and creates a stalled wing then. That is most typically done in loops. Sometimes off the top of a loop, sometimes on the down-line (more so if you miscalculated and then need, or think you need, a tighter arc then - so you might grab too much Elevator quickly).

So probably set it up for LOW rates of 7mm Pitch, and 5mm Roll. High Rates of 9mm Pitch, 7mm Roll. On separate Switches for each axis if you can. Then adjust those amounts to suit what YOU like later.
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Old Jan 22, 2015, 04:50 AM
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Germany, BW, Stuttgart
Joined Mar 2012
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Ah, Pete,

thanx a lot. That´s exactly what I needed.

But the terms you use are confusing me - roll for aileron and pitch for elevator.

I allready know these terms from my 450CP, but there "pitch" is the third axis. What elevator is on a plane is called nick there.

Anyway - I know what I have to do.
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Old Jan 22, 2015, 06:55 AM
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Originally Posted by hongkong View Post
Ah, Pete,

thanx a lot. That´s exactly what I needed.

But the terms you use are confusing me - roll for aileron and pitch for elevator.

I allready know these terms from my 450CP, but there "pitch" is the third axis. What elevator is on a plane is called nick there.

Anyway - I know what I have to do.
Hi Michael,

aileron and elevator means the oars of a plane , roll and pitch means the function.

Rupp
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Old Jan 25, 2015, 01:34 PM
der gerne zweimal billig kauft
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Germany, BW, Stuttgart
Joined Mar 2012
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Finished my Radjet today. Tried to keep it really light for a minimum stall speed. Put it on the scales and all up weight is 356g with an 1000mah / 3S . Not too bad for maiden.

I realized it is not balanced, it´s heavier on the left side. Is this an issue or is it meant to be in order to counteract the torque of the prop? Somewhere at the beginning of this thread coins were stuck to the wings to rebalance it.....

Balancing or leaving as it is?
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Old Jan 26, 2015, 11:51 AM
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Originally Posted by hongkong View Post
Finished my Radjet today. Tried to keep it really light for a minimum stall speed. Put it on the scales and all up weight is 356g with an 1000mah / 3S . Not too bad for maiden.

I realized it is not balanced, it´s heavier on the left side. Is this an issue or is it meant to be in order to counteract the torque of the prop? Somewhere at the beginning of this thread coins were stuck to the wings to rebalance it.....

Balancing or leaving as it is?
I have some Radjets 800 including a speed one (210kmh) and never balanced the wings. If you do you will find no differences in flight.

Why should it better to balance the wings?
You will find no difference in the flight behavior between balanced and not balanced wings.

More influence of flight behavior have the inaccurate foam rudder blades with their linkage.
Modifications by stiff rudder blades with backlash-free linkage will be more effective.
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Old Jan 26, 2015, 06:15 PM
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Well it depends on HOW MUCH imbalance, and a plane's wingspan (leverage).
It will need SOME amount of aerodynamic offset to fly level. eg Aileron trim. Whether that is 0.1mm or whatever....
Weight is also not dynamic like lift, so using lift/aerodynamics to offset a weight is not a linear constant - so as you fly slower the weight 'wins' more then.

Best is to balance it. It is very little effort to do anyway.
But if you did NOT balance it, it will typically not be a major issue anyway - though if it as a lot of imbalance it might....
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Old Jan 27, 2015, 02:42 AM
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For folks that have a setup for speed, how much does it weight?
Mine cannot take off. Every launch was a failure with the nose in the ground. And I'm not a newbie I suspect my 3s 2200mAh to be too heavy which leads to a high stall speed. The CoG should be quite good...
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Old Jan 27, 2015, 04:58 AM
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No, it´s not a big effort. Not at all, a little nail did the trick.
So everything is set up for maiden.

And yes, rupp, I can understand why everyone modifies the jet. The stock prop /motor combo is not the strongest, I found out. Thrust seems to be less than weight. But for maidening at an all up weight of 360g it should be more than enough.

Weather is foul anyway. So I´m not in a hurry.

michael
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Old Jan 28, 2015, 09:39 AM
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Originally Posted by hongkong View Post
No, it´s not a big effort. Not at all, a little nail did the trick.
So everything is set up for maiden.

And yes, rupp, I can understand why everyone modifies the jet. The stock prop /motor combo is not the strongest, I found out. Thrust seems to be less than weight. But for maidening at an all up weight of 360g it should be more than enough.

Weather is foul anyway. So I´m not in a hurry.

michael
Hi Michael,
despite wind influences, a small weight will give better flight properties than a heavvier RJ. 360 g is very good. My 210kmh-Radjet has 626 g start weight.

Bye
Rupp
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Old Jan 28, 2015, 09:40 AM
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Originally Posted by BuBu2 View Post
For folks that have a setup for speed, how much does it weight?
Mine cannot take off. Every launch was a failure with the nose in the ground. And I'm not a newbie I suspect my 3s 2200mAh to be too heavy which leads to a high stall speed. The CoG should be quite good...
My speed setup (210 kmh) has a start weight of 626 g.
Try a smaller lipo about 1000 mAh for first lauching. If it fails again you have to look for another reason.
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Old Jan 29, 2015, 03:12 AM
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Originally Posted by ruppwf View Post
My speed setup (210 kmh) has a start weight of 626 g.
Try a smaller lipo about 1000 mAh for first lauching. If it fails again you have to look for another reason.
You're right that's what I'm going to do. I'll let you know if it finally flies
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