16.3. Event 424: Sport Quickie
16.3.1. Airframe. The airframe specifications for this event are identical to those for Quickie 500 (Event No. 428). See 16.2.1 below.
16.2.1. Airframe
a. Weight. Minimum 3-1/2 pounds, maximum 4-1/2 pounds.
b. Wings.
1) Area: Minimum 500 square inches.
2) Span: Minimum 50 inches (projected), maximum 52 inches (projected).
3) Chord: Constant for at least 47-1/2 inches of span.
4) Airfoil thickness: Minimum 1-3/16 inches for at least 47-1/2 inches of span.c. Fuselage.
1) Depth: Minimum 3-1/2 inches at its deepest point, which must occur within the wing chord.
2) Width: Minimum 2-7/8 inches at its widest point, which must occur within the wing chord. Width and depth points need not coincide.
3) Cross-section: The fuselage shall have a simple, rectangular "box" cross-section with a maximum radius of 1/4 inch at the corners. Diamond-shaped cross sections are prohibited. Fillets or fairings between the fuselage and wing are prohibited. Canopies and turtle decks are acceptable but shall not be included in width or depth measurements. The front firewall shall be a rectangular, flat plate measuring at least 2-1/4 inches by 2-1/4 inches. The perimeter of the front firewall may be rounded to a maximum radius of 1/4 inch.
4) Engine installation: The engine and engine mount shall be fully exposed. No cowling or streamlining of the engine is permitted. A backplate-type radial engine mount that replaces the stock engine backplate may be used so long as it displaces the same crankcase volume as the stock backplate assembly. Corners and edges of the engine mount may be rounded to a maximum radius of 1/4 inch.d. Landing Gear. The landing gear shall be fixed, with at least two main wheels of a diameter not less than 2-1/4 inches. The main wheels shall be at least seven (7) inches apart, measured parallel to the wing span. No wheel pants, wheel spats, or strut fairings shall be used to streamline the main landing gear. Struts shall be either round wire, at least 1/8-inch in diameter, or flat stock no more than 1/8-inch thick. Flat stock may be filed or otherwise shaped to an airfoil cross-section but must have a blunt leading edge. Nose or tail wheels, if used, may be streamlined or enclosed.
16.3.2. Powerplant
a. Engine.
1) Maximum displacement: 0.403 cubic inch.
2) Configuration: Stock, commercially available, front-intake, side-exhaust.
3) Intake: A single carburetor, as supplied by the manufacturer of the engine being used, with a maximum inner diameter of 0.325 inch. The carburetor shall be fully functional and shall be stock, except for longevity-enhancing modifications as follows:(a) Adjustment screws and idle needle valves may be held in place with commercially available thread locker, epoxy, or other adhesives and safetied with rubber bands, wire, or plastic ties.
(b) Barrel retaining screws or pins may be replaced with commercially available screws or pins of harder material and may be held in place with commercially available adhesives. Barrels may be deburred for smoother movement and may be safetied with rubber bands, wire, or plastic ties.
(c) Throttle arms may be modified or replaced.4) Exhaust system: The engine shall be equipped with an expansion chamber muffler or zero-boost muffler as provided by the manufacturer of the engine being used, and having a single exhaust outlet with a maximum outlet area of 0.0621 square inches (equivalent to the area of a round hole measuring 9/32 inch in diameter). The distance from the center of the piston to the centerline of the muffler shall not exceed 2-3/4 inches. The overall length of the muffler shall not exceed 7-1/4 inches, measured from the front of the header to the back of the exhaust outlet. The outside diameter shall not exceed 1-3/4 inches. No modifications to the muffler are permitted except that the muffler may be tapped for a pressure fitting to supply pressure to the fuel system. Tuned mufflers and tuned pipes are prohibited.
5) Fuel feed: Other than muffler pressure, no fuel system pressurization is permitted.
6) Power output: Sport Quickie is intended as an entry-level event for pilots who are new to racing. As such, it is not a suitable event for the use of engines that come with tuned mufflers or otherwise are capable of turning a stock 9 x 6 APC propeller at over 16,500 rpm on the ground. If engines more powerful than this are to be used at a contest, the contest should be sanctioned as Quickie 500 (Event No. 428), not Sport Quickie.b. Propeller.
1) Material: APC composite or a similar, commercially available composite.
2) Dimensions: Minimum diameter nine (9) inches. Nominal pitch six (6) inches, as indicated by the manufacturer’s stamp or packaging.
3) Availability, modification: Propellers shall be commercially available and either supplied by the hosting organization or specified by brand and size in all pre-contest publicity. Propellers shall be stock, except as otherwise provided in paragraph 7.5.2.c. Fuel. The fuel shall be commercially available, containing not more than 15 percent nitromethane, and shall be supplied and dispensed by the hosting organization. The dispensing operation shall include draining the tank of any existing fuel and then filling from a supply container when the pilot brings the aircraft to the ready box.
16.3.3. Special Provisions
a. Routine inspections encouraged: The CD or the CD's designee may elect to check the top three finishers' engines for legality at the end of the contest. In addition, CDs are encouraged to check the carburetor bore, muffler outlet area, and propeller diameter of aircraft that are being weighed immediately after each heat.
b. Rule variations permitted: The engine rules specified below have been used successfully on a local basis to limit the cost or power output of engines used in this event. These and any other variations from the rules specified above should be noted in all pre-contest publicity.
Note: any variation that results in the use of engines larger than 0.403 cu. in. displacement, tuned mufflers, or tuned pipes will result in the event being sanctioned as Quickie 500 (Event No. 428) rather than Sport Quickie.1) Approved engine list: Sample engines are tested and a list of permissible engines is published annually. Criteria include purchase price and power output in both the normal takeoff rpm range and the presumed in-air ("unloaded") rpm range.
2) Prohibited Features: Typically these include Schneurle porting and ABC/AAC metallurgy.
3) Claiming rule: In addition to either or both of the above approaches, a claiming rule allows any contestant to purchase any other contestant’s engine after the contest for a specified price. $100 is suggested.