Hi, my low wing plane is no taking off. It runs around 100metres and climbs slightly after full elevator and then falls.Specification
30inch wingspan, 1000mah 3 cell lipo, 800grams thrust motor, Planes weight with electronics-500grams

Do I need a bigger motor?

Check wing & motor shaft incidence

As you are an intermediate flier I presume that all other points are OK

Everything is ok.

@kiran rc,
Please do the following to enable members to give you help:
1. Attach pics of top view, side view and front view of your model
2. Attach a pic of the plan, or free hand drawing, with all dimensions marked
3. Weigh the model with battery etc, and indicate actual weight (not estimate)
4. Check where the CG is and post distance from leading edge
5. Make, model and Kv of motor
6. Dia/pitch of current prop

Prima facie i suspect that a 30" span model weighing 500gms with 800gms thrust would be extremely hard to fly, definitely not in the trainer category.
We have no idea about your flying experience. We do not even know whether your model is a high or low winger, whether it is a monoplane or bipe, or whether it has dihedral, or how many channels you are using.

If you provide the above data, i am sure you'll get dozens of replies.
Unless of course, like Rai saheb says,

Quote from: sanjayrai55 on November 23, 2014, 07:39:47 PM
As you are an intermediate flier I presume that all other points are OK

Best of luck.

Quote from: K K Iyer on November 23, 2014, 08:01:26 PM


Prima facie i suspect that a 30" span model weighing 500gms with 800gms thrust would be extremely hard to fly, definitely not in the trainer category.
We have no idea about your flying experience. We do not even know whether your model is a high or low winger, whether it is a monoplane or bipe, or whether it has dihedral, or how many channels you are using.

Iyer sir

He has mentioned it is a low winger. He also has mentioned he is an intermediate flier.

Is it a flat wing or profiled? 30" for 500gm as Iyer Sir pointed out is a bit too high!

The model name is 3dx from foamyfactory.com
The cg is ok
Current prop-10x4.7sf
The wing is flat.No dihedral

kiran - post a pic of your plane

in fact two or three - a plan view and a side profile shot...
then we can try and help

your use of the term " falls down" seems to indicate a beginner

have you tried hand launching ?  a 30" plane should be easy to throw

Will a larger motor solve the problem of being heavy? But it would fly fast.

Did not try hand launch.I always have practice taking off the ground

You seem determined to use a bigger motor, totally contradictory to what the description of your problem seems to imply.

Why don't you just do it then? Do let us know the result

ok - after doing some googling I found your plane ...

the 3dx (mini) from foamy factory is supposed to have a weight of 230 gms.. yours is
nearly twice heavier.  and you wonder why it does not fly ?

putting a larger motor will require a larger esc and (and maybe a larger battery ) which
will in turn increase weight ... leading to an even larger motor .... and so on.

try and reduce weight ..

@ sanjay sir,I dont have a large motor right now.I was just doubting the thrust ratios.Here are a few pictures.

Another one.

Quote from: saikat on November 23, 2014, 08:30:32 PM
ok - after doing some googling I found your plane ...

the 3dx (mini) from foamy factory is supposed to have a weight of 230 gms.. yours is
nearly twice heavier.  and you wonder why it does not fly ?

putting a larger motor will require a larger esc and (and maybe a larger battery ) which
will in turn increase weight ... leading to an even larger motor .... and so on.

try and reduce weight ..

please have a look at the pics.It is 3d.Not the same mini 3dx.

Please describe 'climbs slightly after full elevator'
Does it gets into almost Nose up attitude at that stage and then stalls?

@kiran rc,
I apologise if i offended you with my response.
But the fact is that an RC pilot of 'intermediate' level building a 3D model,
And asking a question like 'my plane is no(t) taking off'
Is a self contradiction.
Sir,
If nothing else, at least indicate your CG position.
If possible also your motor and prop details.
Only trying to help.
Pm me if you don't like my inputs and i'll stop!

Edit: sorry, careless of me as pointed out by sanjayrai55.

Quote from: K K Iyer on November 23, 2014, 09:44:20 PM
@kiran rc,
I apologise if i offended you with my response.
But the fact is that an RC pilot of 'intermediate' level building a 3D model,
And asking a question like 'my plane is no(t) taking off'
Is a self contradiction.
Sir,
If nothing else, at least indicate your CG position.
If possible also your motor and prop details.
Only trying to help.
Pm me if you don't like my inputs and i'll stop!

no sir not at all

Quote from: IndianHobbyShop on November 23, 2014, 08:59:59 PM
Please describe 'climbs slightly after full elevator'
Does it gets into almost Nose up attitude at that stage and then stalls?

no, not nose up.The cg is balanced.

@Iyer sir, cg is around 30% from leading edge,  motor ishttp://www.rcbazaar.com/products/1483-odin-2210-kv1200-thrust-810-gms.aspx
Propeller is already described.10x4.7sf

@kiran rc,
Battery down. Will revert tomorrow.
Meanwhile you could perhaps try a 9x6 prop?
Will share details of a friend's retired Rare Bear that i repaired and test flew (successfully!) today.
Similar specs to yours. And a handful!

Quote from: kiran rc on November 23, 2014, 10:06:40 PM

Quote from: IndianHobbyShop on November 23, 2014, 08:59:59 PM
Please describe 'climbs slightly after full elevator'
Does it gets into almost Nose up attitude at that stage and then stalls?

no, not nose up.The cg is balanced.

Well, I wasn't referring to CG there. I was referring to your comment about 'Full Throttle' which makes perfectly balanced planes stall (mostly for beginners though)

@kiran _rc u call this a low winger.... this is a mid winger dude
@Sanjay rai sir kyun le rahe ho