Help! Help me tune my trainer plane control throws

[erfan_m14]

Hello everyone.
I built my first rc plane, it's an trainer plane, I built it using a plan and instruction video.
And about the radio controller, I built a DIY radio controller using Arduino.
Yesterday I went out to try it, It was a little windy, I gave the plane to my friend to throw it against the wind, and I was holding the radio controller. And it was my first experience flying an rc airplane (except playing with a simulator on my iPad)
He throw it smoothly against the wind and the motor was in full throttle and I was pushing right joystick all down so the elevator was all up to avoid airplane from hitting the ground. As soon as he threw it, it went to a high attitude so quickly in just 2 seconds, about 10 meters or so. And I couldn't control it well and it crashed. I think one thing was about the wind and another thing is about the control throws. I recorded a video showing the throws. Can anyone tell me if they are too much and how much is good for my first flights?
Here is the link of the video:

 

[erfan_m14]

And here is a photo when I balanced the airplane

 

[JasonK]

you stalled your wing by holding back on the elevator. you need to keep the plane closer to level so it keeps speed. That doesn't sound like a throws issue (could be a contributing factor), but a piloting error.

 

[Timmy]

I can't see the link. The throws look alright. maybe a bit much on the elevator but sometimes the planes seems uncontrolable because the pilot cranks the stick too much. You only need to gently nudge the plane in the direction you want it to go.

 

[JasonK]

yah... rudder throws look a bit much. I would also suggest programming some expo.

 

[Tench745]

I would say that for a first flight you want it as calm as you can get so that anything the plane does is obviously from your inputs and not the wind. Teaching yourself to fly in wind is a great way to break planes and hide mistakes you're making.
I would say that your rudder throws look ok, the ailerons look good for an aerobatic plane, but maybe too much for a beginner, and the elevator is WAY too much. Most FT planes have somewhere between 10 and 16 degrees of throw on the controls. Your elevator looks more like it has 45° up and 30° down.
Your CG looks pretty good to me.

If the plane is built and trimmed properly you should be able to launch at 1/2 to 3/4 throttle with the controls neutral. The plane should be thrown firmly but smoothly with the nose level or just slightly upwards and it should fly away on it's own just fine. Once it's in the air and at flying speed you start controlling it. Launching with full up-elevator almost undoubtedly put you into a stall and made the resulting crash an almost guaranteed outcome.

 

[Timmy]

I would say that for a first flight you want it as calm as you can get so that anything the plane does is obviously from your inputs and not the wind. Teaching yourself to fly in wind is a great way to break planes and hide mistakes you're making.
I would say that your rudder throws look ok, the ailerons look good for an aerobatic plane, but maybe too much for a beginner, and the elevator is WAY too much. Most FT planes have somewhere between 10 and 16 degrees of throw on the controls. Your elevator looks more like it has 45° up and 30° down.
Your CG looks pretty good to me.

If the plane is built and trimmed properly you should be able to launch at 1/2 to 3/4 throttle with the controls neutral. The plane should be thrown firmly but smoothly with the nose level or just slightly upwards and it should fly away on it's own just fine. Once it's in the air and at flying speed you start controlling it. Launching with full up-elevator almost undoubtedly put you into a stall and made the resulting crash an almost guaranteed outcome.

agreed

 

[Merv]

Great looking plane. The CG looks about right. I agree with the others you could reduce the throws a little, I’d recommend reducing the throws by 20-30%.

You over controlled the plane, the hard climb caused the airspeed to drop, with little air flowing over the wings, they lost lift, they stalled. Gravity took over and plane dropped from the sky.

Next time DON’T hold up elevator. You want a good firm toss, like you were tossing a football 20 yards. The toss should be upward 15 degrees or so. You want full throttle and a little elevator to hold the plane on the 15 degree climb until you get about 200 feet high. Then pull the throttle down a little and maintain 200 feet.

 

[erfan_m14]

Hello and thanks everyone so much.

you stalled your wing by holding back on the elevator. you need to keep the plane closer to level so it keeps speed. That doesn't sound like a throws issue (could be a contributing factor), but a piloting error.

That's right I tried to be a better pilot this time and didn't hold back the elevator, but I have still some problems.

I can't see the link. The throws look alright. maybe a bit much on the elevator but sometimes the planes seems uncontrolable because the pilot cranks the stick too much. You only need to gently nudge the plane in the direction you want it to go.

I tried not to crank the sticks too much but I think as it's my first experience, I can't control it smoothly.

yah... rudder throws look a bit much. I would also suggest programming some expo.

Thank you so much for your advice.

I would say that for a first flight you want it as calm as you can get so that anything the plane does is obviously from your inputs and not the wind. Teaching yourself to fly in wind is a great way to break planes and hide mistakes you're making.
I would say that your rudder throws look ok, the ailerons look good for an aerobatic plane, but maybe too much for a beginner, and the elevator is WAY too much. Most FT planes have somewhere between 10 and 16 degrees of throw on the controls. Your elevator looks more like it has 45° up and 30° down.
Your CG looks pretty good to me.

If the plane is built and trimmed properly you should be able to launch at 1/2 to 3/4 throttle with the controls neutral. The plane should be thrown firmly but smoothly with the nose level or just slightly upwards and it should fly away on it's own just fine. Once it's in the air and at flying speed you start controlling it. Launching with full up-elevator almost undoubtedly put you into a stall and made the resulting crash an almost guaranteed outcome.

I reduced elevator throw. And didn't change anything else. And tried to fly like what you said but I wasn't successful.

Great looking plane. The CG looks about right. I agree with the others you could reduce the throws a little, I’d recommend reducing the throws by 20-30%.

You over controlled the plane, the hard climb caused the airspeed to drop, with little air flowing over the wings, they lost lift, they stalled. Gravity took over and plane dropped from the sky.

Next time DON’T hold up elevator. You want a good firm toss, like you were tossing a football 20 yards. The toss should be upward 15 degrees or so. You want full throttle and a little elevator to hold the plane on the 15 degree climb until you get about 200 feet high. Then pull the throttle down a little and maintain 200 feet.

I was expecting myself to fly like what you said this time but I couldn't actually.
Well thank everyone so much for all your advices. I try to do what you said and this time I could fly much much better than before but still I have many problems. I put the video below. Everything is clear in the video, if you turn up the volume, you can hear that I reduced throttle in the 8th second of the video because I thought maybe I can control it better. And after that when you don't see the plane in the video, the plane was stalled as I remember and I was sure that it will crash so I reduced throttle to zero and then the plane crashed.
My guess is that I just overconctrolled the plane and I'd better to reduce the ailerons throw maybe by 50%? And I guess I would better to put 1 or 2 degrees right thrust angle for the motor, am I right?

 

[Timmy]

you did pretty good! Not sure about the thrust angle but if you want you can reduce the throws more, however as you gett better at flying I recomend increasing the throws again.

 

[Merv]

so I reduced throttle to zero and then the plane crashed.
My guess is that I just overconctrolled the plane and I'd better to reduce the ailerons throw maybe by 50%? And I guess I would better to put 1 or 2 degrees right thrust angle for the motor,

You must have power to fly, unless a crash is eminent, keep the power on. At this point, your only goal is just keep the plane in the air.

It’s hard to tell from the video exactly what is going on. Planes are much easier to fly when you get them trimmed out. Get the plane about 200 in the air, then trim it to fly straight and level at full throttle. Move the trim tab the same direction you are holding the stick to keep the plane in the air. If you are push the stick to the left, move the trim tab left.

I would not change any thrust angles until the plane is trimmed out.

 

[Tench745]

At this point I'm guessing at solutions based on what I saw.
You can tell that you're over-controlling. There are two ways to fix this: Either practice until you can move the stick the small amount you need to fly, or reduce your elevator throws some more then practice practice practice. Once you have some experience you can up the throws again if you want to.

I don't think it's the cause of your problems, but something I'm noticing is the hand-launch. The guy throwing the plane kind-of just pushes it up vertically and lets go with very little push forward. You want the plane to leave your hand near flying speed, so he'll need to throw it harder and without the vertical pop this time.
Furthermore, the plane looks like it accelerates really slowly. Just double check that your prop is on the correct direction; numbers facing forward.

 

[erfan_m14]

you did pretty good! Not sure about the thrust angle but if you want you can reduce the throws more, however as you gett better at flying I recomend increasing the throws again.

Thank you sooo much for your advice.

You must have power to fly, unless a crash is eminent, keep the power on. At this point, your only goal is just keep the plane in the air.

It’s hard to tell from the video exactly what is going on. Planes are much easier to fly when you get them trimmed out. Get the plane about 200 in the air, then trim it to fly straight and level at full throttle. Move the trim tab the same direction you are holding the stick to keep the plane in the air. If you are push the stick to the left, move the trim tab left.

I would not change any thrust angles until the plane is trimmed out.

Thank you for your advice, I have mixed the rudder with the ailerons, as you can see in the post #1

At this point I'm guessing at solutions based on what I saw.
You can tell that you're over-controlling. There are two ways to fix this: Either practice until you can move the stick the small amount you need to fly, or reduce your elevator throws some more then practice practice practice. Once you have some experience you can up the throws again if you want to.

I don't think it's the cause of your problems, but something I'm noticing is the hand-launch. The guy throwing the plane kind-of just pushes it up vertically and lets go with very little push forward. You want the plane to leave your hand near flying speed, so he'll need to throw it harder and without the vertical pop this time.
Furthermore, the plane looks like it accelerates really slowly. Just double check that your prop is on the correct direction; numbers facing forward.

Thank you so much. That's right my friend didn't throw it much well. I just checked the propeller direction and it was fine.

One thing that I just remembered is that the plane would go down and I had to push the elevator up to gain attitude again, then I would release the elevator and again the plane would loose attitude, you can see that in the video too. You can see that plane loose attitude several times but as I remember I didn't push the elevator down at all. What could be the cause of this? I haven't made any down thrust angle, maybe the plane was a little nose heavy?

 

[Timmy]

maybe the plane was a little nose heavy?

possibly but a nose heavy plane still flies better than a tail heavy one! You can slide the battery back a bit and that should fix your problem