Help! FT Spitfire not taking off

[Planelover104]

Hi,

Built a FT Spitfire from a speed built kit that is refusing to take off. Have attempted to fly it 4 times already but every time it has crashed without moving forward even by a few feet and/or taking off. What could be the issue? Feel that it does not have enough power or thrust even after having calibrated the ESC.
Have installed the following electronics:
1400 kv motor
30 amp ESC
2200 mAh battery
8" x 5" propellor

Thanking you in anticipation

 

[Tech3811]

What size is your motor? There should be two different numbers on it, a KV number, and a size number(or you could send a link or picture of the motor) I think that is where the problem is.

 

[Ryan O.]

I agree with @Tech3811 , there should be other motor specs than KV. Also, how many cells is the battery, because if it is 3 cell you can use a 10x4.5 prop, and if it is 4 cell you should use a 9x4.5 prop. Either way, it seems like your plane may be slightly under propped. Also check that your prop's not on backwards, the numbers should be facing forwards. The last thing I'd check for is the prop nut. If it is slightly loose the prop won't generate much thrust.

 

[Planelover104]

What size is your motor? There should be two different numbers on it, a KV number, and a size number(or you could send a link or picture of the motor) I think that is where the problem is.

I am using a Sunnysky X2212-9 KV: 1400 Motor

 

[Planelover104]

I agree with @Tech3811 , there should be other motor specs than KV. Also, how many cells is the battery, because if it is 3 cell you can use a 10x4.5 prop, and if it is 4 cell you should use a 9x4.5 prop. Either way, it seems like your plane may be slightly under propped. Also check that your prop's not on backwards, the numbers should be facing forwards. The last thing I'd check for is the prop nut. If it is slightly loose the prop won't generate much thrust.

It’s a 3cell battery

 

[Tech3811]

Yeah, that motor seems pretty small. If you don't want to pay 70 bucks for a c-pack, look for a 2218 1,000kv motor and esc, and you will have a good c-pack equivalent. I think the small motor plus the small prop just might be adding up to your failures. Good luck!

 

[mrjdstewart]

check your prop and make sure you have it on correct and that the motor is spinning in the right direction. the numbers on the prop should always face forward in the direction of flight and if your motor is spinning the wrong way just swap 2 wires around.

that motor should be plenty to get it flying, you must having something mixed up.

good luck,

me

 

[BATTLEAXE]

I agree with @mrjdstewart, it so sounds like the prop is on the wrong way. Although the motor is small for this plane it should get it at least somewhat airborne and if decently trimmed it will fly at a higher throttle, more then just a few feet. Your prop is the issue but you should use a larger motor so you can run larger props for larger planes. Ideally your prop should be 1/4 of our wing span, I believe the Spitfire is a 42" wingspan. Meaning you should be running a 10", a 9" at the smallest.

The 2212 1400kv/30 amp ESC combo that I have been using works really well, but on planes with a 30-36" wing span. They are lighter and take a 8" prop very well. The largest battery I would use with it too will be an 1800mah, cuz thats all weight it has to carry. I would recommend using a 1300mah 3s for those smaller motor packages. Its basically a B pack motor with a little more juice given the higher KV rating, but that also means it has to run a smaller prop. The same size motor in a 1000kv would run a larger prop.

Go up to a C pack equivalent what the plane is made for and you will be right where you want to be with that plane. Or you could downscale it to fit the motor pack you have, but thats building a new one. Again if you are to do that I would reduce the battery size.

All in all i would say your issue is the prop for your immediate problem, but you do have options to make a better system

 

[quorneng]

Planelover104
This a performance table for the Sunnysky X2212-9 KV: 1400 Motor

This suggests with a 3s battery and a 8x5 you should be getting at least 800g of thrust if the battery is fully charged which I suspect will make it move pretty fast!
How much does you Spitfire weigh ready to go?

 

[Bricks]

Are you trying to take off on grass?

 

[Planelover104]

Yeah, that motor seems pretty small. If you don't want to pay 70 bucks for a c-pack, look for a 2218 1,000kv motor and esc, and you will have a good c-pack equivalent. I think the small motor plus the small prop just might be adding up to your failures. Good luck!

On Flight Test Store - the C pack consists of Motor - Radial 2218/1180kV. Is there a big difference between that and what I have i.e. X2212-9 KV: 1400 Motor?

 

[Planelover104]

Planelover104
This a performance table for the Sunnysky X2212-9 KV: 1400 Motor
View attachment 182876
This suggests with a 3s battery and a 8x5 you should be getting at least 800g of thrust if the battery is fully charged which I suspect will make it move pretty fast!
How much does you Spitfire weigh ready to go?

The weight of my ready to fly plane is approximately 820 grams. As per my understanding my motor can't take a propeller bigger then 9"x5". Do you think a 9"x5" prop will work?

 

[Planelover104]

Are you trying to take off on grass?

No I am hand-launching it.

 

[Ketchup]

No I am hand-lunching it.

Do you have a description of exactly what is happening? Like is it just nosediving even with full up elevator, or wants to roll to the left or something? With your motor the plane should at least go somewhere. Are the letters on your prop facing forwards and is the motor spinning in the right direction? Do you have a video or pictures of the plane?

 

[Planelover104]

I agree with @mrjdstewart, it so sounds like the prop is on the wrong way. Although the motor is small for this plane it should get it at least somewhat airborne and if decently trimmed it will fly at a higher throttle, more then just a few feet. Your prop is the issue but you should use a larger motor so you can run larger props for larger planes. Ideally your prop should be 1/4 of our wing span, I believe the Spitfire is a 42" wingspan. Meaning you should be running a 10", a 9" at the smallest.

The 2212 1400kv/30 amp ESC combo that I have been using works really well, but on planes with a 30-36" wing span. They are lighter and take a 8" prop very well. The largest battery I would use with it too will be an 1800mah, cuz thats all weight it has to carry. I would recommend using a 1300mah 3s for those smaller motor packages. Its basically a B pack motor with a little more juice given the higher KV rating, but that also means it has to run a smaller prop. The same size motor in a 1000kv would run a larger prop.

Go up to a C pack equivalent what the plane is made for and you will be right where you want to be with that plane. Or you could downscale it to fit the motor pack you have, but thats building a new one. Again if you are to do that I would reduce the battery size.

All in all i would say your issue is the prop for your immediate problem, but you do have options to make a better system

Many thanks for your detailed reply. Shall buy a new prop as you suggest. Also do you think I should review the ESC that is 30 amp?

 

[danskis]

30 amp is fine

Possible option:

http://www.valuehobby.com/power-sys...runner-airplane/gforce-e450-1200kv-motor.html

 

[Ryan O.]

Many thanks for your detailed reply. Shall buy a new prop as you suggest. Also do you think I should review the ESC that is 30 amp?

it should be fine

 

[cranialrectosis]

Before you spend any money, can you post video with sound?

It's difficult to understand what you are experiencing from your description.

There are multiple possible causes and solutions and lots of us to help but the symptoms are a tad vague.

In lieu of video, we are making stabs at the most common issues we deal with on our forums based on what we think you are experiencing.



The simplest, most common solution is that you have the prop on backwards. @BATTLEAXE and @mrjdstewart and I all read your problem and this is our first thought. A backwards prop howls like a wolf at a full moon. Video with audio will prove this right or wrong. All props have letters or numbers on the front (top) of the prop. These should face forward.

Number two has to be reversed channels on your remote. My first two planes (because I didn't learn from the first) were hand launched and then faceplanted into the dirt and broke. This is because I had my elevator control backwards on my remote. I was telling the remote to pull up. The remote was telling the plane to nose down...

Number three is going to be CG. How does your plane glide when it is fully loaded (everything except the prop) and you just toss it over the grass? If the plane doesn't glide, it won't fly. How does your plane glide?

Number four is probably going to be something like, did you charge your lipo? Lipos don't ever get fully discharged (it ruins them if you do) and ESCs power down when they detect a low voltage battery. This spins the motor slowly and provides less power. It is the ESC attempting to prevent you from blowing up your lipo. What is the current charge on your lipo?

There are more. Lots and lots more things that can go wrong. These are just four of the most common reasons someone's plane "won't take off".

Video of the issue will go a long way toward helping us help you.

Finally, welcome to the FliteTest forums!

 

[Planelover104]

Before you spend any money, can you post video with sound?

It's difficult to understand what you are experiencing from your description.

There are multiple possible causes and solutions and lots of us to help but the symptoms are a tad vague.

In lieu of video, we are making stabs at the most common issues we deal with on our forums based on what we think you are experiencing.



The simplest, most common solution is that you have the prop on backwards. @BATTLEAXE and @mrjdstewart and I all read your problem and this is our first thought. A backwards prop howls like a wolf at a full moon. Video with audio will prove this right or wrong. All props have letters or numbers on the front (top) of the prop. These should face forward.

Number two has to be reversed channels on your remote. My first two planes (because I didn't learn from the first) were hand launched and then faceplanted into the dirt and broke. This is because I had my elevator control backwards on my remote. I was telling the remote to pull up. The remote was telling the plane to nose down...

Number three is going to be CG. How does your plane glide when it is fully loaded and you don't put a prop on, you just toss it over the grass? If the plane doesn't glide, it won't fly. How does your plane glide?

Number four is probably going to be something like, did you charge your lipo? Lipos don't ever get fully discharged (it ruins them if you do) and ESCs power down when they detect a low voltage battery. What is the current charge on your lipo?

There are more. Lots and lots more things that can go wrong. These are just four of the most common reasons someone's plane "won't take off".

Video of the issue will go a long way toward helping us help you.


Finally, welcome to the FliteTest forums!

Hi,

Thanks for your reply. It Is very encouraging and would help me sort this out

1) I checked the direction of the prop and it’s correct.
2) I checked my control surfaces and they are all correct.
3) I will chuck the plane and check if it glides. However I have checked my CG and it’s correct.
4) Yes my lipo’s were fully charged when I flew my plane all 4 times.

 

[cranialrectosis]

If all these are good then again @BATTLEAXE has probably the best guess... weight. That plane is pretty big for your motor and prop. If you are loading the plane down with a big, heavy lipo, you will probably have problems.

What is the All Up Weight (AUW) of your plane, fully loaded, lipo and all?