hai all
this one belongs to my friend from kottayam,flew it yesterday but forgot to take take the camera.flew it nicely today... sorry for no landing sessions as my memory card is full  i am using a 3s 20c lipo with 25 amp brushless esc . esc is very hot after 5 minutes of flying , any sugessions. one thing i really impressed is by the sound

santhosh

Usual suspects... wrong prop, too heavy a plane (too heavy a lipo ?  what mAH are you using). 

This model is quite famous/common here now as a local shop got many in stock, and I saw people hovering it !

Nice flight, and the sound is really cool

Nice plane and nice flying Flies well at really slow speed

Santosh, where did you buy the plane from and how much did u pay?

hi anwar
not much idea abt the prop and motor,i got it assembled almost by 99%.using  1500 Mah lipo  but i have to give almost 90 % throttle for to keep it airbone

For one, try flying it with a smaller lipo, like an 800 mAH one, and see if things improve. 

20(C) x 1.5 Amps(1500mah) = 30 Amps discharge capacity.

At 25 Amps ESC you are using only 83% of the full capacity.
If you want to exploit the full potential of the battery without overheating the ESC then you need 30 Amps Esc or more.

surely will not recommend smaller battery since with 25 Amps ESC if ESC is heating up power system is surely drawing more than 25 amps

Can be more specific if you clarify on the Motor used and propeller sizes.

Quote from: sundaramvelar on January 26, 2010, 11:17:04 PM
surely will not recommend smaller battery since with 25 Amps ESC if ESC is heating up power system is surely drawing more than 25 amps

The reason I mentioned a smaller battery was to reduce the weight, which might be one reason he is having to fly at 90% throttle and such high amps draw. With the lowered weight, he would not draw as many amps.

But you are right. It would need to be a higher C battery at lower mAH, especially if he is still having to fly at higher throttle. And the flight time will of course be lower.

The other alternatives of replacing parts of the power-system are messier (except for the prop, if there are other ones of different dimensions handy).

For me it looks like a wrong prop. With that kind of sound you should be revving the motor at a very high rpm. Ironically, the model barely floats in the sky. I would expect the model to be lightning fast.

That is the very first thing I suggested too. But it would be rare typically for people to stock pusher props of various sizes. 

So the next quick test was to see if lesser weight helps.

Thunder tiger EP Profile mig29 is available with along with power pack motor OBL29 2900 KV and prop 5 x 5
recomended additional items required to complete as per OEM are as follows  
03 x sub-micro servo
ESC
Micro RX
Micro TX
Lipo 3S 1000-1600mAH

In my humble opinion if battery and motor is not heating up and only ESC is heating up, choke point is ESC. Capacity of ESC needs to be increased. One can try to mount the heat sink of ESC in the air draft of the props to achive a better cooling. I had done that in my Profile Techone F-16 with 3800KV 64mm EDF, 30 Amps ESC and 1300mah 25C 3s Lipo. I had to always fly at half throttle since it was very fast. I could do only short sprints of full throttle.

As such if one is using a recomended 1500 Mah 20 C battery appropriate ESC to go with would be 30-40 Amps ESC as mentioned earlier.

with the kind of sound it was making Mr izmile's point of view has lot of weigtage. I hope you are using recomended well balanced 5 x 5 props

Looks like it is always flying at high alpha. Typically this is because the the model is nose heavy. To prevent it from diving, you have to compensate with high reflex. This results in high drag and also usually sluggish rolls.

If my observation on alpha is correct, try moving the CG backwards and reduce the reflex trim to maintain level flight. You'll find the model getting faster and control response will improve. Reflex should not be more than a few degrees on a properly trimmed delta model.

the prop i am using is a 5*5, and the motor is 2900 kv.izmile u r right as i too was expecting this will fly at high speeds, now flies like an easy star, not much option to play with ,will try with small mah batteries as anwar said.Rajesh can u explain what is high alpha, i dont understand,anyway will try with moving the cg backwards. see the pics of nose section rebiult by me  aftr a crash ( tnx to anwar's x ray film method)

Santhosh

High alpha means high angle of attack.

To explain it a bit more, high alpha flying involves flying a plane with its nose lifted high compared to the tail.  In this position, the props are throwing a large part of the air downwards, instead of throwing it all backwards.  So the plane does not go as fast as in level (non high alpha) flying. High alpha is the base for many 3D moves.

clear now

High alpha is a deliberate 3D Move under taken with a very good air frame with slats down, elevator up and aircraft nose up. It requires only 50% - 75% throttle and not 90% throttle.

A model which compels you to keep nose up always even at full throttle is a clear sign of lack of adequate thrust (propulsion). Though all aircraft are designed to be slightly nose heavy, more faster the model is more nose heavy it is required to be. A model which has a nose on the heavier side will surely compel you to keep the nose up at slow speed, but if it is having adequate thrust, in full throttle when leveled will surely pickup good speed though will lose altitude. However good speed is good lift and so though lose altitude initially will gain after gaining speed. from the flight video more than heavy nose, only thing evident is the lack of propulsion.

A 2900 KV motor 5 x 5 Prop is appropriate combination for a high speed model. if the propeller is not chipped/ broken and is well balaced it should give very good speed at 2900 KV with 20 C 3s power pack. OBL29 if I am not wrong, runner can dia should be 29 mm is likely to be between 350 to 500 watts. At min 350 watts will surely require a 30 Amps plus ESC.

Wish you will change your ESC before it fries and gain good propulsion. good luck and happy flying.