Control Line General

CLG-09-1 - Allow use of high strength fiber lines in events that currently use stainless steel cables.

General Para.5 .......All lines used to control flights shall be steel music wire or metal of equivalent strength, or braided cables made from gel-spun ultrahigh molecular weight polyethylene(GSUMP). ......

(additional paragraph)
The following chart gives the equivalent sizes for GSUMP when substituting them for seven strand stainless steel cables.

.021 stainless= .021(.53 mm) 150 lb. test 30 lb. monofilament equivalent diameter
.018 stainless = .0181(.46 mm) 100 lb test 20 lb. monofilament equivalent diameter
.015 stainless = .0153(.38 mm) 80 lb test. 18 lb monofilament equivalent diameter
.012 stainless = .0122(.31 mm) 50 lb. Test 12 lb. monofilament equivalent diameter
paragraph 5.3.1 (added paragraph)

Gel spun braided lines (Spectra(tm) or Dyneema (tm) fiber) may be terminated two ways. The first is to fold the line back against itself and tie the loop in a double overhand knot by forming a loop with the doubled line and passing the folded end through the loop twice. Lubricate the line with water or saliva to assist in pulling it smoothly tight. To terminate lines using line clips the line should be tied to the clip using a “half blood knot”. Loop the line through the clip, wrap the line around the standing end 5-6 times and bring the free end back through the loop on the line clip. Lubricate the knot with water or saliva and pull tight smoothly.

Logic:
The gel-spun ultra high molecular weight lines offer many advantages over steel wires, both solid and stranded. The GSUMP material is does not kink. It is almost totally immune to fatigue (the lines will not break from vibration at a point where they have been bent). The high visibility colors make it much easier to see the lines laying on the ground. They are highly resistant to wear when rubbed against each other (approximately four times more wear resistant). They stretch less and are easier to make up when they do wear and need replacement. The lines are made of many, many fibers so when wear and fiber breakage are seen they can be replaced in a timely manner.

Control Line Racing: add to paragraph. 5.3 Refer to the control line general rules for control line materials and line construction.

Control Line Navy Carrier: add to paragraph. 4.1 Refer to the control line general rules for control line materials and line construction.

Control Line Precision Aerobatics: add a new paragraph, 4.1 Refer to the control line general rules for control line materials and line construction.

Combat: add a new paragraph: 3.5 Refer to the control line general rules for control line materials and line construction.

Control Line Special Events, (Control Line Endurance, Event 332): add to paragraph. 5 Refer to the control line general rules for control line materials and line construction.

Control Line Scale (Event 508): add to paragraph. 4 Refer to the control line general rules for control line materials and line construction.

Submitted by: Phil Cartier, AMA #6249

CLG-09-2 – This proposal clarifies the definition of profile model in CL competition events.

Change: 10. Profile Definition. The fuselage of a profile model resembles that of a conventional airplane in the side (profile) view and appears as a thin flat sheet in the plan (top) view. The engine shall be completely exposed from the mounting lugs to the cylinder head and shall not have any type of fairing. Additional reinforcements such as plywood nose doublers and cheek cowls on the opposite side of the engine (for side mounted installations) are permitted. Cheek cowls may extend from the prop drive washer to a point 25 percent of the root chord back of the leading edge at the root, and may be faired in. In the case of an inverted or upright engine installation, the engine mounts may protrude from the fuselage sides by may not be faired in.

Class/Event	Max Width including Plywood Doublers	Max Cheek Cowl Width
1/2 A Proto	1/2 inch	3/8 inch
Scale Racing	5/8 inch
Slow Combat	3/4 inch	3/4 inch
Carrier	3/4 inch	3/4 inch
Slow Rat Racing and Rat Racing	3/4 inch

To: 10. Profile Definition. The fuselage of a profile model resembles that of a conventional airplane in the side (profile) view and appears as a thin flat sheet in the plan (top) view. When a conventional, single cylinder, internal combustion engine is used, the engine shall be completely exposed from the centerline of the crankshaft to the top of the cylinder head when viewed perpendicular to both the crankshaft centerline and the cylinder centerline. In the case of internal combustion engine with multiple cylinders, the preceding rule shall apply to all cylinders with allowances made by the officials for appropriate mounting of the engine. No fairing may be added to the engine which violates the “completely exposed” requirement of the previous sentences, and the engine cylinder shall not be contoured to present a streamlined cross section to the airflow. Additional reinforcements such as plywood nose doublers and cheek cowls or fairings are permitted within the width limits defined in the accompanying table. Such additional fuselage reinforcements may extend from the prop drive washer to a point 25 percent of the wing root chord back of the wing leading edge at the root and may be faired in. Cheek cowls used in Racing events may be of unlimited width, but may be used only on the side opposite the engine and only on models with side-mounted engines. Engine mounts may protrude from the fuselage sides beyond the width limitations of the table. They may extend no further aft than 25 percent of the wing root chord back of the leading edge at the root. Any such protruding engine mounts shall be of constant cross sectional shape and dimensions, without tapering. The rear portion of those mounts shall terminate in an angle of at least 45 degrees to the longitudinal axis of the fuselage unless they terminate within the wing structure. Nacelles, as used on multi-engine models are subject to the requirements of this definition.

Profile Fuselage Width
Class/Event	Maximum Fuselage Width	Max Width of Additional Reinforcements
1/2 Proto	1/2 inch	3/8 inch
Scale Racing	5/8 inch	No limit
Slow Combat	3/4 inch	3/4 inch
Navy Carrier	3/4 inch	3/4 inch
Slow Rat Racing and Rat Racing	3/4 inch	No limit

Logic:
There are ambiguities in the present rules, and the present rules provide no guidance for radial engine mounting or any engine mounting configuration other than horizontal (side) mounting using lugs on the sides of the engine aligned with the crankshaft. The increasing use of electric motors adds additional questions on how to accommodate the common radial mounts of these motors which are generally wider than the reinforcements allowed in the present rules. Electric motors are cylindrical, but have no “cylinders” as implied in the rules. The protruding engine mounts portion of the rule is ill defined as to what constitutes “faired in”. The same poor definition applies to the requirement that the engine “not have any type of fairing”. Wings and fuel tanks constitute “fairings” in that they can reduce the drag of an engine cylinder, but common practice has allowed such installations as not violating the fairing rule. “Plywood doublers” mentioned in the table are nothing more than reinforcements and should be treated as such if they exceed the maximum fuselage width since neither the material (plywood), the configuration (doubler) nor the dimensions can be determined in most finished models. The reinforcements specification for other than side mounted internal combustion engines is subject to interpretation, but is almost universally allowed. Only fuselages are discussed in the current rule, but nacelles are relevant in multi-engine models. This proposal clarifies all of these issues without changing the generally accepted (but not codified) interpretations of the existing rule.

Submitted by: Richard Perry, AMA #243