The Academy of Model Aeronautics welcomes the world to the 2024 F2 World Championships for CL Model Aircraft, to be held in Muncie, Indiana, on August 12-17.

By Paul Gibeault

The F2 Control Line (CL) World Championships have been going on since 1960, but the event was last held in the US in 2004 here in Muncie, Indiana, at the International Aeromodeling Center (IAC). AMA is very pleased to offer our competitors an upgraded CL facility this year, featuring freshly paved flying circles. We are expecting well over 200 competitors from 30 countries competing in four individual disciplines, which, in the end, will ultimately yield four new CL World Champions. The events that will be featured are explained below.

F2A Speed: The rules are quite simple, in that the maximum engine size is 2.5cc, and models must conform to a fixed surface area loading. All models fly on a fixed line length of 17.7 meters and run on regulation no-nitro fuel. This is similar to the “Top Fuel Dragster” class, where the airplanes have evolved into a very aerodynamically sleek and asymmetric layout. Top speed engines produce over 2.5 hp and are exquisitely tuned to run at over 40,000 rpm, so bring your ear defenders! To make the podium, speeds of just over 300 kph will be needed. Current Junior and Senior World Speed Champions Ivan & Alex Valishev from the US will be here to defend their titles.

F2B Precision Aerobatics: This event is not unlike ballet, where the pilot must fly their model gracefully through a precision sequence of maneuvers in front of a panel of international judges. Each maneuver is judged out of 10 then multiplied by a difficulty factor, expressed as “K” in the maneuver descriptions. The aerobatic models are the largest of the CL models and are built and finished like show models. Unlike in AMA Stunt, there are no bonus points for finish. Nonetheless, these models are built and finished to perfection, as many fliers feel it contributes (if ever so slightly) to the entire overall flight pattern presentation. This is the one class where electric motors are becoming dominant, which makes this class the quietest of all to watch.

F2C Team Race: The essence of F2C is that the class is fast, with technically advanced models that are quite tricky to operate and fly. It is very physically demanding for the pilot. Racing three up and extracting one’s best performance is essential at this level. Sometimes referred to as a “young man’s event,” F2C Team Racing involves a high degree of fitness in the pilots. These 220-kph models have evolved into the half-moon-shaped flying wing layout. Often built with composites, they are very light at approximately 315 grams for instant acceleration, and they are powered by very highly tuned (25,000 rpm) 2.5cc racing diesel engines. Diesel engines are used due to the regulation 7cc tank size restriction. Glow engines simply cannot achieve the required range that these models require. The pitmen in these races are equipped with a sophisticated pressure fueling device on their arms, which refills the model’s tank in seconds. They can also change the fuel blend from tank to tank during the race if needed. These models are flown three up for 100-lap heats with two refueling pit stops. A good pit stop is an amazing sight, as it can be performed in mere seconds. It takes both good piloting and consistently excellent pit work to make it to the 200-lap final race.  All events are paused to enjoy the 200-lap race, which is often very exciting. Hearing protection is suggested, as three Team Racing models running together on full song are loud! 

F2D Combat: Combat is arguably the best spectator event. With 50 entries at the preceding World Cup, Combat promises to be a very exciting event!  F2D Combat is simply aerial dogfighting! Two pilots, each flying a model aircraft, fly against each other in the same circle in a 4-minute bout. Each model tows a particularly colored paper streamer, and each pilot attempts to take cuts from their opponent’s streamer with the propeller of their own aircraft. Combat models have always been of the flying wing layout, but the current models are very highly developed to be both maneuverable and rugged. F2D models are powered by high performance 2.5cc glow motors on regulation fuel, and they’re flown on 15.9-meter lines.  Fuel shutoffs are now mandatory for safety reasons, after a few models were cut off of their lines during Combat matches. Watching these models chasing each other’s streamers at well over 160 kph is always exciting. Top competitors must bring a fleet of models with them, because the attrition rate due to crashes and midair collisions is high. 

All competitors and spectators are most welcome to enjoy our championships at the IAC. Come enjoy the National Model Aviation Museum and souvenir gift shop. The National Museum of the United States Air Force in Dayton, Ohio, and Indianapolis Motor Speedway are also nearby attractions. See you all soon!

For competition results and a real-time blog page, visit  https://2024clwc.org/.