FT Flyer - keeps crashing

[lleemon]

Just built a FT Flyer hoping for a gentle easy flyer and the few attempts I have made are all but that. Here is a video of some attempts I have made all ending in crashing. It keeps wanting to nose dive down.

Any ideas why?

Thanks in advance.
Lee

[FT Flyer Specs]
Motor: E-flite Park 370 Brushless Outrunner Motor, 1360Kv
Prop: Gemfan 8045 (8x4.5)
ESC: BL Heli - 30 amp (Xt-60 Connectors)
Servos: Emax ES08A II 8.5g Servo (x2)
Transmitter: Spektrum DX6
Receiver: Spektrum AR610
Battery: Loong-Max Tipple 800mAH 2s 20c Lipo Battery (XT-30)

 

[Snarls]

It may sound trivial, but it looks like your elevator is reversed.

 

[cranialrectosis]

Looks a lot like the park where I learned all about reversed channels... :black_eyed:

 

[GeraldNL]

Hi lleemon,

I could only think of 3 things

1 You have a wrong trim setting. Give te plane a lot of up trim when taking of. When flying slowly remove up trim until the plane flies level on its own. If this is your problem you could keep flying like this but you will lose control range.

I would advice to land the plane and remember the angle the elevator needs to fly straight. Then lossen the screws and level out your servos to 0 and then fasten your screw again. This will give you the up trim you need and will give you back all your control area.


2 your cg is of (the balance of the plane). Check your plans and balance out your plane
3 your elevator is reversed. (doesn't look like it but could be)


Hope it helps

 

[lleemon]

Don't think it's reversed, when I pull back to take off it goes up. As I go back to center it goes down.

 

[lleemon]

Thanks GeraldNL for the constructive response. I will give them a try.

 

[SlingShot]

Up elevator should move the control surface UP.

If that is correct then you are likely nose heavy. Verify the controls.

 

[lleemon]

Up elevator should move the control surface UP.

If that is correct then you are likely nose heavy. Verify the controls.

That seems backward to me. Have I always been doing it wrong?

When the right transmitter stick is pushed up, the elevator should move down.
When the right transmitter stick is pushed down, the elevator should move up.

 

[BridgeInspector]

It is definitely an odd behavior.

Your controls look correct to me.

Few questions,
Have you calibrated the ESC so that your throttle response is linear for the entire stick range?

Are you also dropping the throttle when it noses over? It could be that your thrust angle is off, so a throttle up position is picking the nose up on takeoff and then when you let off the throttle it drops the nose.

 

[lleemon]

It is definitely an odd behavior.

Your controls look correct to me.

Few questions,
Have you calibrated the ESC so that your throttle response is linear for the entire stick range?

Are you also dropping the throttle when it noses over? It could be that your thrust angle is off, so a throttle up position is picking the nose up on takeoff and then when you let off the throttle it drops the nose.

I will have to do some research on the ESC/throttle response question. Not sure.

I typically take off 3/4 throttle and really when it comes down is when I stop pulling up. I did adjust elevator subtrim a little and will try flying again. It didn't seem like a lot but will see if that fixes it.

Thanks for the tips.

 

[Munk]

I'm gonna echo what some people have been saying; it looks like you're either nose heavy or that you might need a little up trim on the elevator.

The nose only seems to drop when you try to go into level flight, so maybe you could also try physically adjusting your elevator throw so that it's always up a little bit. You could do that by either shortening your control rod or unscrewing your elevator servo horn and reattaching it one "tick" forward.

My money's on nose heavy though. Try taping some small weights (some coins can do the trick) to the back to push the CG towards the tail.

 

[SlingShot]

That seems backward to me. Have I always been doing it wrong?

When the right transmitter stick is pushed up, the elevator should move down.
When the right transmitter stick is pushed down, the elevator should move up.

What you demonstrated on the video was correct. Pull back on the stick to go up.

 

[SlingShot]

I'm gonna echo what some people have been saying; it looks like you're either nose heavy or that you might need a little up trim on the elevator.

The nose only seems to drop when you try to go into level flight, so maybe you could also try physically adjusting your elevator throw so that it's always up a little bit. You could do that by either shortening your control rod or unscrewing your elevator servo horn and reattaching it one "tick" forward.

My money's on nose heavy though. Try taping some small weights (some coins can do the trick) to the back to push the CG towards the tail.

He should be able to adjust the CG with his battery placement.

 

[raybeau528]

I watched the build video to get familiar with this model and it appears you built it per plan.

The CG location is indicated on the wing. Does your CG balance ok at that mark?

I'll echo what some others have said - trim the elevator until it flies level with no input. Gain some altitude and adjust the trim pot until it levels out. If you're not comfortable doing that have someone else adjust the trim while you fly. I've done it that way myself.

You might even reduce the throws a little so you don't have quite the abrupt movement.

Ray

 

[JimCR120]

While I agree the direction of travel looks correct, one other thing to rule out is which direction you move the stick to pitch up. Sounds redundant maybe but when I passed the tx to my son, he assumed pushing up on the stick would make the plane go up. Normally pulling back on the stick pitches the nose up.

Not knowing what you know could have us assuming too much. And if you already knew this, please don't be offended at my ignorance of your skills.

 

[raybeau528]

While I agree the direction of travel looks correct, one other thing to rule out is which direction you move the stick to pitch up. Sounds redundant maybe but when I passed the tx to my son, he assumed pushing up on the stick would make the plane go up. Normally pulling back on the stick pitches the nose up.

Not knowing what you know could have us assuming too much. And if you already knew this, please don't be offended at my ignorance of your skills.

Good point. I once told my brother to give it some up elevator and he pushed the stick forward. Had a little conversation about terminology.

Ray

 

[SlingShot]

Look at Mode 2

and look at this

 

[DarkFire]

That seems backward to me. Have I always been doing it wrong?

When someone refers to either up or down elevator, they are referencing the position of the elevator, not the stick. Up stick is down elevator and down stick is up elevator.

 

[Montiey]

I'd try just chucking the plane, and see how well it will glide with minimal input. It's possible that at higher airspeeds, the wing warps, or the thrust angle causes the craft to pitch wildly.

 

[Snarls]

It could also be a bad servo that fails when too much load is applied. So it looks fine on the bench, but in flight will fail when too much up elevator is applied.