To provide a racing event that may easily be flown “three up” and which employs relatively inexpensive and easily constructed control line racing models. To encourage and promote the success of the “average” control line flyer in control line racing competition.
All AMA control-line unified racing rules apply, except as modified in the following descriptions.
It is imperative that the performance level of this event be maintained such that is always possible to safely race “three up” on stranded lines. If at any time it is felt that the event must be changed from the three up format for safety concerns or that solid lines are required, then the event rules should be immediately modified so as to reduce the aircraft performance level. It is recommended that this event be reviewed by the National Control Line Racing Association (NCLRA) on a yearly basis. As a guideline, if nominal speeds surpass 105 MPH (17.14 sec/7 laps), then the allowable venturi should be reduced by 0.010 inches. The sport of three up control line racing should be preserved at all costs even if individual equipment is made obsolete.
3.1. Model Description:
Models will be of profile construction only as defined in the AMA Control Line General Section. The control system consisting of lead-outs, bell-crank, push-rod and control horn will be totally exposed and external to the normal airplane contours. The line connections to the model will be external to aircraft wing tip.
3.1.1. Landing Gear
The aircraft must have fixed landing gear and must rise of the ground (ROG). Single fixed wheel gear is permissible.
A mounting plate of metal or other material of no more than 1/8 inches thickness may be used between the lugs of the engine and the motor mounts. The lead-out tip guides may be inset into the wing but should be no more that ½ inch in length.
Use of cast pan or metal engine crutch is not allowed. The lead-out wires will not be recessed into the wing, the push-rod will not be mounted inside the fuselage, nor will the bell-crank be allowed to be mounted inside the fuselage.
Maximum total displacement shall be 0.4028 cubic inches (6.6 cc). Engines must production units assembled from factory available production parts. Engine and parts must have been produced in quantities greater than 500 and all must be or have been available through normal retail outlets in the USA. Part substitution shall be limited to catalog listed parts produced in quantities greater than 500 units for the engine being altered and available commercially to anyone from parts except as noted in the following paragraphs. No material or part may be added except as noted in the following paragraphs.
The “engine” is defined as the complete unit, read to run, needing only prop, fuel and starting voltage except the glow plug, venturi and/or restrictor, spray-bar and needle valve, gaskets, bolts, drive washer, front washer, prop nut, shims, piston ring(s)(if used) and ball bearings(if used) need not be considered part of the production unit. These parts are not subject to the rules regarding quantitiy or source. In addition, chrome plating of a production cylinder is allowed.
The glow plug must have a thread dimension of ¼-32.
The engine must be of the front intake configuration. All air for the combustion process must come through the crankshaft. Altering nominal sub-port induction, timed holes in the case and sleeve or other techniques to circumvent the requirement that all air come through the specified venturi opening are not allowed.
Only single by-pass port engines are allowed. The engine as purchased and as used shall be of the single by-pass configuration. No schneurle or PDP porting is allowed.
No ABC or AAC piston/sleeve configurations are allowed.
No variable area carburetors shall be allowed. Each engine shall be equipped with a venturi and spray-bar meeting the following restrictions:
- · The venturi shall have an inside circular bore of not more than 0.292 inches. The venturi will maintain this diameter for at least 0.155 inches at the throat of the venturi where the spray-bar will be located at the midpoint of this area
- · The spray-bar assembly will be located precisely through the centerline of the venturi bore and shall have a constant circular cross section of diameter not less than 0.153 inches for the portion in the throat of the venturi
The complete engine/venturi/spray-bar system shall weigh less than 10.5 ounces.
3.3. Fuel Tank
The fuel tank must be outboard of the face of the motor mounts where the engine is bolted, excluding any mounting plate as described in section 3.1.2. Fast fills are allowed.
Glow fuel shall contain a maximum of 10% nitro-methane with a minimum of 20% lubricant and the rest methanol. Glow fuel shall be supplied by the contest management. The contest management may provide fuels with differing lubricant quantity and composition for contestant choice, which shall be announced in advance of competition.
4. Equipment Allowances and Prohibitions
Hot gloves are allowed
Shutoffs are allowed during the race and are recommended for safety.
No tuned pipes, mufflers or exhaust extensions are allowed
Pressure fuel systems are not allowed, with the exception that the fuel tank vent tubes may be directed into the airstream.
5. Race Definitions
5.1.1. Lines Size
Lines shall be 0.018 inches multi-stranded steel.
5.1.2. Line Length
Line length is 60 feet ± 6 inches measured from the center of the handle to the center line of the fuselage.
5.2.1. Pre-Race Requirements
The airplane and the entire control system shall undergo a pull test of 35 pounds before competing.
All preliminary heats and the final race require the completion of a fixed number of laps. Each contestant shall be allowed at least two qualifying heat races.
The preliminary heats are 70 laps long with one (1) mandatory pit stops required. Three contestants with the top heat times proceed to the final.
The final race is 140 laps with three (3) mandatory pit stops. Fastest time wins.
6. Other Information
6.1. Event Notes
The event director may disqualify any entrant who is not in keeping with the spirit of intent of this racing event.
6.2. Publishing Notes
This initial draft was written 10 May 2012. It is believed that is set of rules is only a reformation of the NCLRA rules and therefore any aircraft that satisfies the NCLRA “Quickie” criteria is acceptable.