How to Adjust That High-Powered AMA Gas Free Flight
TWO words sum it all up . . . "Very Carefully." Experienced competition-minded free-flight fliers, representing untold numbers and hours of flight testing, echo these words . . . "Very Carefully." I'd like to share with you this experience, and much needed know-how, to help you adjust high-powered, high-performance models. Whether you're a sport flier, or already competition-minded, if you understand the aerodynamic theory, and apply the construction and adjusting techniques, you'll be spared traumatic test flights, fatal crashes, and even improve the caliber of your competitive flying. To begin with, let's put the problem in perspective. What is a high-powered, high-performance AMA Gas free-flight model? High powered refers to the engine. For example, it has features such as: Schnuerle porting; ABC (aluminum-bronze-chrome) piston and sleeve; uses fuels containing more than 50% nitromethane; operates only on a pressure fuel system; no muffler; and turns in excess of 20,000 rpm. High performance refers to the model's climb and glide, which is consistently capable of maxing out in dead air. AMA Gas refers to the AMA Gas classes, such as A, B, C, etc., for free-flight models, flown according to the free-flight Categories with either 2-, 3-, or 5-minute maxes.
How to Adjust That High-Powered AMA Gas Free Flight - Part 2
THERE are three elements leading to a consistent max in dead air, namely, a fast steep climb, a smooth transition, and a low sink-rate glide. The key to success is selecting trim adjustments that are in harmony with each other from launch to the end-a max. How do you go about making a selection? Answer. Fly it, try it, and fly it again. The main ingredients of our new generation free-flight models are: high speed climb, super engine power, and a quick response to adjustments. It makes sense then to concentrate on the adjusting techniques affecting the climb pattern. Once the climb is adjusted to our liking, the glide can then be ironed out. And if the glide adjustment also affects the climb, we'll have to re-adjust the climb again before proceeding with the glide. This seesaw procedure is needed because adjusting techniques, such as shifting the Center of Gravity (CG), and decalage, are often used to adjust both climb and glide.
U.S. FF Championships
THE 15TH RUNNING of this annual contest was a competition-oriented extravaganza of 42 events concentrated into three days of flying from sunrise to mid-night. Some events were flown in presunrise dead air, others during midday in the presence of humongous thermals. One event was flown at night under star-studded skies, and Indoor events were flown in two
