read the last two pages of the http://texascombat.com forum on cobra. I built two cobras as per instructions. I had to add 8 oz of weight to the standard length nose to get it to balence. Another pilot in my club built a cobra totally independantly and had to add the same amount of weight. I removed the weight and extended the nose until it balenced. I talked to lee little about this. mine weighs the same as his(if i remove the 8 oz). he uses a heavier motor mount and a stabdard size servo for throttle. The test flight will tell me today. If it flies well I will just make a few spare tongues that can be field replaces and leave it that way.