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Title: building a giant scratch built
Post by: prashant_rc on February 04, 2012, 10:25:44 PM

Hi

I am building a giant scratch built along with Anwar Ul Haq sir,

Wing span 64 inches (more than 5 feet wing)

fuselage of 50 inches

will be using 4260-600 kv motor with power of 1425 watts

my all up weight would be around 1800 to 2000 grams

I hope the above motor would have enough thrust to pull up with 14 inch prop

plz suggests watts thrust ratios

Regards
Prashant

Title: Re: building a giant scratch built
Post by: Sumeet on February 04, 2012, 10:37:10 PM

If you need your plane to do aerobatics, then 140~150 watt/lb power loading would be good. For same keep the thrust to weight ratio more than 1:1. The motor you have mentioned above with 2000gm of AUW would be good. But a lot better would be to wait for seniors to post here.

I hope this helps.
Thanks.

Title: Re: building a giant scratch built
Post by: prashant_rc on February 04, 2012, 10:47:05 PM

Thanks sumeet

As per my knowledge

50 watts per pound for flying
100 watts per pound for aerobatics
150 watts per pound for 3D aerobatics

working on thrust, motor output of mine is 1425 watts, want to know thrust in grams

Title: Re: building a giant scratch built
Post by: Sumeet on February 04, 2012, 10:50:11 PM

Thrust to weight ratio more than 1:1 means the thrust should be greater than the AUW. So, for a plane of 2000grm AUW, the Thrust should be >2000grm.

Title: Re: building a giant scratch built
Post by: prashant_rc on February 04, 2012, 11:02:36 PM

s ur right it is a trainer model with dihydral wing

would like to know my motor thrust in grams (given as 1425 watts power)

Title: Re: building a giant scratch built
Post by: Sumeet on February 04, 2012, 11:28:36 PM

Well, then around 80% of AUW would do.

RC India

RC Models => Electric Planes => Topic started by: prashant_rc on February 04, 2012, 10:25:44 PM