In 1979 the late Ralph Prey wrote an article on how to trim high power Gas Models for Model Aviation magazine that became the standard for all power FF. With so many new fliers and in particular in Electric, making making this information available again and this time electronically on the Internet just makes good sense. The trim techniques have not changed over the years. And most electric flown today falls into the high power category. All motors sold by Texas Timers for electric FF would fall into the high power class.

Where the article talks about Center of Gravity (CG) changes, for electric flight it is common to also shift the battery location fore or aft  rather than moving the motor location. And, today, convenient lead weights are now available in the form of adhesive backed ones for fan blade balancing (big box hardware stores) and even more convenient thin adhesive back lead for golf clubs (big box sporting goods stores).   

The original article has been converted by Paul Bradley into the convenient PDF format and is an exact copy of the original with a few typos corrected. Paul has done a fantastic job to ensure the text and graphics are reproduced so exactly and with such such high quality.

We are grateful to Ralph for his permission to republish and also to Model Aviation for their approval to make this classic article available, again.

You will need the Adobe Reader to see this article. ENJOY and believe it as it is the truth. Read the first sentence over and over until you never forget it!

Open the PDF file