My first maiden.....didn't go well.

Ducky84

Member
Sooo I had my maiden today on my first RC craft (Simple Cub) I set my expectations for a crash as I know it's part of the learning experience, and well, that's exactly what happened!

I could have picked a calmer day, winds were around 10mpg with occasional gusts, but I really wanted to get out.

On takeoff, I had about 50% throttle and the aircraft lifted off but took an immediate left turn, like a full circle almost. It was also wobbling all over the place. I tried to steer it in for a smooth crash landing but it came in kinda hard. Damage was only a busted prop, so I'll take it out again on a calmer day.

Regarding the hard left at takeoff....Anything I could check for to help with the next flight? My rudder looked level, and all the other flying surfaces looked even.

Only thing that I noticed was the rubber bands holding the wing on the top were not holding on very tight. It seemed like the wing was maybe bending a tad in the wind, so I may double up the rubber bands.
 

GliderFlyer

Elite member
Sooo I had my maiden today on my first RC craft (Simple Cub) I set my expectations for a crash as I know it's part of the learning experience, and well, that's exactly what happened!

I could have picked a calmer day, winds were around 10mpg with occasional gusts, but I really wanted to get out.

On takeoff, I had about 50% throttle and the aircraft lifted off but took an immediate left turn, like a full circle almost. It was also wobbling all over the place. I tried to steer it in for a smooth crash landing but it came in kinda hard. Damage was only a busted prop, so I'll take it out again on a calmer day.

Regarding the hard left at takeoff....Anything I could check for to help with the next flight? My rudder looked level, and all the other flying surfaces looked even.

Only thing that I noticed was the rubber bands holding the wing on the top were not holding on very tight. It seemed like the wing was maybe bending a tad in the wind, so I may double up the rubber bands.
Ah, the left turn on takeoff.
That kind of turn is usually caused by the torque from a right-spinning prop and can be resolved by adding right thrust, which counters the left force.
By the way, is this a three channel or four channel airplane? By that I mean does it have ailerons?
-Good luck in future RC flights(y)
 

BlockerAviation

Legendary member
Sooo I had my maiden today on my first RC craft (Simple Cub) I set my expectations for a crash as I know it's part of the learning experience, and well, that's exactly what happened!

I could have picked a calmer day, winds were around 10mpg with occasional gusts, but I really wanted to get out.

On takeoff, I had about 50% throttle and the aircraft lifted off but took an immediate left turn, like a full circle almost. It was also wobbling all over the place. I tried to steer it in for a smooth crash landing but it came in kinda hard. Damage was only a busted prop, so I'll take it out again on a calmer day.

Regarding the hard left at takeoff....Anything I could check for to help with the next flight? My rudder looked level, and all the other flying surfaces looked even.

Only thing that I noticed was the rubber bands holding the wing on the top were not holding on very tight. It seemed like the wing was maybe bending a tad in the wind, so I may double up the rubber bands.
Crashing is definitely part of the fun in this hobby! Sounds like you either don't have any/enough right thrust, or you ground looped on takeoff. Either way it's fixable
 

Tench745

Master member
Some amount of left turning tendancy is to be expected.
Make sure your horizontal stabilizer is parallel with the wing and 90degrees to the vertical stabilizer.
Make sure there isn't a twist built into the wing.
Make sure your ailerons (if you have them) are set the same.
Make sure the wing is centered on the fuselage

On my small Spirit of St Louis I use 4 rubber bands, I would do the same for the cub.
 

Ducky84

Member
Yeah this is a 4 channel setup with ailerons.

I'll go through and measure that everything is straight again.

Couple of you guys mentioned adding or adjusting right thrust. What do you mean exactly?
 

Tench745

Master member
Yeah this is a 4 channel setup with ailerons.

I'll go through and measure that everything is straight again.

Couple of you guys mentioned adding or adjusting right thrust. What do you mean exactly?

The motor can be slightly angled to the right (as looking from the cockpit) to help fight the motor/prop from turning the plane to the left.
You can add right thrust pretty easily by placing a washer between the motor and firewall on the left side to angle the motor to the right.
 

Ducky84

Member
The motor can be slightly angled to the right (as looking from the cockpit) to help fight the motor/prop from turning the plane to the left.
You can add right thrust pretty easily by placing a washer between the motor and firewall on the left side to angle the motor to the right.

Ah I see, yeah I'll give that a shot!
 

Hai-Lee

Old and Bold RC PILOT
You fell for the newbie caution syndrome.
You took off with 50% throttle after a shortish take off run. Sadly that was always going to result in a roll and crash without doubt.
For your next flight try keeping the plane on the ground until it has a lot of flying speed. The greater the speed the better and more effective are the aerodynamic control surfaces.
Ideally do not take off until the plane is really moving fast along the ground and GENTLY, (VERY GENTLY) apply a little up elevator and then release. The plane should just rise into the air smoothly and of course all of the flight surfaces will be working as expected..

Just what i teach my students for their first take off!

Have fun!
 

Ducky84

Member
You fell for the newbie caution syndrome.
You took off with 50% throttle after a shortish take off run. Sadly that was always going to result in a roll and crash without doubt.
For your next flight try keeping the plane on the ground until it has a lot of flying speed. The greater the speed the better and more effective are the aerodynamic control surfaces.
Ideally do not take off until the plane is really moving fast along the ground and GENTLY, (VERY GENTLY) apply a little up elevator and then release. The plane should just rise into the air smoothly and of course all of the flight surfaces will be working as expected..

Just what i teach my students for their first take off!

Have fun!

So I just wanted to say thank you to everyone for the feedback!

I'm happy to say that today's flight went much better. I was able to launch, fly a couple circles and actually land the thing!

However I did run into a challenge with takeoff. I built my wheels a little funky, and due to the weight of the aircraft, the wheels bow out. So I had to hand launch.

When I launched, I gave it 75% throttle (Power pack C) and tossed it. Just like my first flight though, the aircraft just went haywire. Launched up, did some weird 180, came back at me and was just not in control.

This time though I was able to power through it and when it leveled out, I had full control. No trim adjustments needed, it flew perfect. (What an awesome feeling)

So my question is, is there a technique or something to hand launching that I may not be doing right? Should I be chucking it as hard as I can?
 

Pieliker96

Elite member
So I just wanted to say thank you to everyone for the feedback!

I'm happy to say that today's flight went much better. I was able to launch, fly a couple circles and actually land the thing!

However I did run into a challenge with takeoff. I built my wheels a little funky, and due to the weight of the aircraft, the wheels bow out. So I had to hand launch.

When I launched, I gave it 75% throttle (Power pack C) and tossed it. Just like my first flight though, the aircraft just went haywire. Launched up, did some weird 180, came back at me and was just not in control.

This time though I was able to power through it and when it leveled out, I had full control. No trim adjustments needed, it flew perfect. (What an awesome feeling)

So my question is, is there a technique or something to hand launching that I may not be doing right? Should I be chucking it as hard as I can?
The goal should be to give the plane a somewhat firm toss forwards with a slightly nose-up attitude and little pitch rate, preferably with some throttle on. I wouldn't describe a hand launch as "chucking it", it should be more gentle than that. It also shouldn't be thrown with a high angle relative to the horizon, as that can make it easier to stall.
Try experimenting with different throttle settings in the air at low airspeeds. If it wants to pitch up or turn or do anything you don't want it to, you'll have to correct for those when hand-launching. My dad built a FT Tiny Trainer that would want to climb like a homesick angel at low airspeed and high power unless he gave it a good bit of down-elevator. Adding some down-thrust in addition to the right thrust and/or a radio mix can decrease this tendency if need be.
The goal isn't to get the plane flying as soon as it's out of your hand but to give it enough of a push so it can get flying with the altitude and airspeed you've already given it, what that push is will depend on the plane and the pilot.
 

Merv

Site Moderator
Staff member
.... On takeoff, I had about 50% throttle....
I agree with Hai-lee, 50% throttle is the most likely problem. Next time use 100% throttle.

When a plane is low to the ground, 12 inches or so, the air get's compress between the ground and the wing. This ground effect generates more lift, when the plane moved higher, the ground effect is reduced & your wings were not generating enough lift to fly. It could also be that you were climbing too fast. As the plane climbed it lost speed resulting in a lost of lift. Either way, the solution is more power.
 

GliderFlyer

Elite member
So I just wanted to say thank you to everyone for the feedback!

I'm happy to say that today's flight went much better. I was able to launch, fly a couple circles and actually land the thing!

However I did run into a challenge with takeoff. I built my wheels a little funky, and due to the weight of the aircraft, the wheels bow out. So I had to hand launch.

When I launched, I gave it 75% throttle (Power pack C) and tossed it. Just like my first flight though, the aircraft just went haywire. Launched up, did some weird 180, came back at me and was just not in control.

This time though I was able to power through it and when it leveled out, I had full control. No trim adjustments needed, it flew perfect. (What an awesome feeling)

So my question is, is there a technique or something to hand launching that I may not be doing right? Should I be chucking it as hard as I can?
It is also possible that your control throws are too high.
 

Merv

Site Moderator
Staff member
S......Should I be chucking it as hard as I can?
Your "chuck" should be about the same as tossing a baseball 50-75 feet. Just a good solid throw, no need to throw the plane as you would a base ball from left field to home.
 

Ducky84

Member
Thanks guys!

Alright, I have some things to try for my next flight. I think I may have been throwing it to far upwards which was causing it to launch straight up and lose control, as well as maybe putting too much force behind my throw. I'll try some more flights later in the week as the weather allows.
 

Hai-Lee

Old and Bold RC PILOT
Hand launching can cause almost as many crashes as flying inexperience.
I have observed many failed hand launches in my time and so I tend to use a sort of a bungy launcher, well it is closer to being a catapult.
See https://forum.flitetest.com/index.php?threads/the-best-20-i-invested.53587/

It can launch a heavy model, without the motor turning, at more than flying speed and into a test glide for hundreds of meters which is more than enough time to apply motor power and take control. It NEVER throws the plane into the ground or nose up. It also never launches the plane sideways or in a spiral.

When hand launching it is wise to try to get good flying speed and this is my preferred method. Many people use the baseball analogy for the required throw but I prefer to consider the launch of a javelin. Slightly nose up and with some gusto but with a flat and level follow through.

Just my thoughts of course!

Have fun!
 

clolsonus

Well-known member
Thanks guys!

Alright, I have some things to try for my next flight. I think I may have been throwing it to far upwards which was causing it to launch straight up and lose control, as well as maybe putting too much force behind my throw. I'll try some more flights later in the week as the weather allows.

It's really easy to toss the airplane straight up, even if you aren't trying to. Other's have better advice than me, but when I've tried to teach people how to hand launch, I tell them all the stuff, exactly what to do, what not to do. The very last thing I remind them is don't throw it straight up. Then they throw it straight up. What are you going to do?!? :)

So anyway, it's a natural thing to do I guess. As others have said, you really just want a nice firm toss that is as close to the climbout angle and speed you want as possible. You just want it to fly straight out of your hand and continue in a straight line. That takes practice, and it's a little different for every airplane. Once you get the hang of it though it just feels and looks right, but /you/ have to send it in the right direction at the right speed and right pitch attitude.

Oh and in case no one else mentioned it or you haven't seen this somewhere else, it is very important to toss directly into the wind (and land into the wind.) I imagine you knew that already if you flew some successful flights, but thought I'd mention it just in case.

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Hey there. Ducky84 here, for some reason my account was banned...no idea why...

Anywho, I had another complete failure of a launch today where upon release the plane cut hard left and into the ground.

However I think I know why this time.....turns out I may have been giving it 100% without knowing it.

I found that past 50% throttle on the stick, there was no change in engine speed. At 50% tje engine was actually full out.

I think the reason why is on my controller the inputs on the screen for throttle go from -100 to +100. At 50% on the stick that value on the screen goes to 0. When the stick is fully up the screen shows +100.

I think due to miscalibrating my throttle inputs it resulted in me putting way too much power causing torque steer and driving it left into the ground.

Thats my running theory.
 

sprzout

Knower of useless information
Mentor
Your "chuck" should be about the same as tossing a baseball 50-75 feet. Just a good solid throw, no need to throw the plane as you would a base ball from left field to home.

Agreed. My planes that I fly with a hand launch are pretty simple to launch. I generally put my planes up to 75%-100% throttle, depending on what I'm throwing (some will likely tell me I'm nuts for that, but that's what I do) and give it a light toss. My P-38 wants to just lift out of my hand, with only a slight toss, and will fly pretty much from the start of the toss. My P-51, which is also a hand launch plane, does much the same, wanting to glide right out of my hands with very little toss.

For what the OP is flying, a light, simple toss would do. Think of throwing a football to your buddy standing a couple yards away - you're not trying to throw it THROUGH them to knock them down, just a light toss, where you're pointing your hand at where you want the plane to go when you've let go. I've found that throwing it almost straight, like you're just trying to get it to go a long distance across the field, rather than up at an angle, is more effective; you'll feel the plane want to lift up out of your hand when you're throwing it at a certain point for it to just go out and up.

Working with a throw like this, where you're focusing on pointing where you want it to go, will help you to not bring your arm across your body in an arc; that arc is what will make the plane want to turn and roll because the wings aren't level, or give you what you think is torque steer and pull to one side. If you're REALLY worried about your form, make a paper airplane and throw it straight - that's the exact same method and toss that you want for these planes, and it's the exact same principle.