Former Spad-

What type of kit are you buying servos for? The majority of "typical glow-fuel kits/ARFS" on the market will work just fine with "standard" servos. Most mfc's. are pretty good about suggesting alternate size servos if necessary.

The dynamic pressure model used on one the websites mentioned in one of the other posts works fine if you want to estimate servo torque. I wrote an article for RCM Magazine in 1998 based on dynamic pressure. Despite having a NASA engineer review my article before submitting it to the magazine, I received numerous letters from folks, without credentials, telling me I was wrong. The handfull of appreciation letters I received were from licensed Professional Engineers.

I guess I am a little surprised there are not a swarm of replies to this topic with differing viewpoints. Historically this has been one of those hot debate topics.

Good luck with your project!