indoorcolo

The F1D class is recognized as the ”Formula 1” of indoor modeling and is the class flown in the Indoor World Championships held every two years where teams from countries from all over the world compete for the individual and team world indoor duration titles. The F1D class is not only the largest of the indoor duration classes with a wingspan of 22 inches and an overall length of 30 to 33 inches but is also one of the lightest with a minimum airframe weight of 1.2 grams. The rubber weight is limited to 0.6 grams making the total weight of a completed model less than two one-dollar bills.

Construction of these models requires the highest levels of craftsmanship and the very lightest of materials and construction techniques to produce a competitive model. With a propeller diameter of 18 inches that rotates at about 40 to 55 RPM, the models almost seem to defy gravity and hover in mid-air. The most advanced models are built with variable pitch propellers (the pitch or angle of the blades changes during the flight to increase efficiency) producing a model that is capable of flight times approaching 40 minutes. Check out some of the videos in the Links Section to see how they fly. Below is a picture of an F1D built by John Kagan.