13               USRA Provisional Class: Warbird

13         TIMEFRAME

            The Warbird Class will remain Provisional at least through 2016

13.1     INTENT

The Warbird class is intended to provide a less expensive means of introducing experienced R/C pilots to giant scale racing and to increase membership in the USRA.  The specifications have been developed to create a multi plane event using readily available 50cc sized Warbird ARFs and kits along with a variety of sport type gas engines that will allow R/C pilots to experience giant scale pylon racing with minimal risk and investment. Once a competitor has grown proficient in this class, they will be encouraged or required to move on to one of the other Giant Scale USRA classes as per section 12.8.


13.2.1  GENERAL - All pertinent AMA / USRA safety rules apply. Servos operating all control surfaces must be of sufficient size with at least 69.5 in.oz. of torque.  The battery capacity must be a minimum of 1200 mAh or 200 mAh per servo whichever is higher.

13.2.2  AIRCRAFT – Any ARF or Kit meeting all requirements as listed in this section will be eligible.  No modifications to the airframe that would change the planform or dimensions will be allowed.  Model must be a scale representation of a single-engine, propeller driven, WWII-era Warbird. “Warbird” is defined as any WWII era aircraft that was initially factory configured with guns, cannon, rockets, or the ability to drop bombs or torpedoes. Racing versions of Warbirds will not be allowed.  No clipped wings, small canopies, removed scoops, or any other deviations that change the scale outline, planform, or dimensions. When in doubt, if the rules don’t say that you can do it, then you can’t.

13.2.3 WEIGHT - Ready to fly dry weight cannot be less than 16 pounds or more than 30 pounds

13.2.4 LANDING GEAR – Fixed or Retractable landing gear will be allowed if it is applicable to the full-size aircraft.

13.2.5 Spinner - Must be the scale diameter and of metal construction.  No plastic allowed.

13.2.6 Aircraft Size -  Aircraft will have a wingspan between 82” and 96”.  Aircraft will have a minimum wing area of 1200 square inches.

13.3    ENGINES (internal Combustion) – Any commercially available gasoline engine from 40cc to 65cc will be allowed. Engines must be unmodified. Engines can be magneto or electronic ignition. Converting gasoline engines to glow fuel will not be permitted.

13.3.1 MUFFLERS – No tuned pipes or tuned mufflers are allowed. Header pipes with no expansion chambers will be limited to 8” in length.

13.3.2 ENGINE SHUT OFF – Aircraft must display positive engine shut down via the transmitter during the engine run-up and radio range check.

13.3.3 FUEL TANK – Must carry sufficient capacity for at least 7 minutes of flight time.

13.3.4 FUEL – Contestants will provide their own fuel as suitable for the engine they have chosen. Fuel or additives such as Hydrazine, Nitrobenzene and Tetranitromethane will not be permitted. Nitrous Oxide systems are not permitted.  Proper handling and safety precautions for fuel must be observed by and is the responsibility of the contestant at all times.

13.4    ELECTRIC MOTORS – Electric power systems will be allowed. Motor and battery combined weight shall not exceed 14 pounds. Battery capacity should be sufficient for 7 minutes of flight time.

13.5    PROPELLERS – Any commercially available non metal propeller can be used.

13.6    Awards – The class winners will be presented with awards.  No prizes, cash, or year-end points championships will be awarded.

13.7    RACE COURSE – The standard 1600 ft. course is normally used for giant scale racing, however for smaller flying sites a 1200 or 1000 ft could be used. It is recommended that typical USRA race procedures be used. This information can be obtained via the USRA Internet site at www.usrainfo.org.

13.8    PILOT PARTICIPATION – The Warbird class is open to all participants who can demonstrate safe flight with a Warbird class aircraft.  Participants that win 2 gold races will be required to move on to another USRA class.  Aircraft that win 2 gold races will also be deemed ineligible for further participation in this class.