Rule 11 - TOURNAMENT EQUIPMENT / TECHNICAL
11.1: Boat Performance Requirements
Boats must have the performance necessary to obtain and maintain the required boat speeds (14.4 and 15.6) while towing any skier under tournament conditions. Tournament Sanction Applications must include a list of the boats planned for use in the competition. These must be approved by the WSC Technical Committee.
11.2: Boat Dimensions
Overall length shall be approximately 5 m but must not exceed 6.5 m. The beam shall not be less than 1.8 m and not more than 2.5 m.
11.3: Towing Pylon
Boats shall be equipped with a towing pylon on the centerline of the boat approximately amidship, which shall be a minimum of 65 cm and a maximum of 1.2 m above the water when the boat is standing still with no occupants aboard.
11.4: Boat Engines
Either inboard or outboard power may be used.
11.5: Boat Radios
The tow boat(s) shall be equipped with adequate two-way radios.
11.6: Speedometers
Boats shall be equipped with at least two accurate water speed measuring devices operating on separate pickup tubes and preferably with tachometers.
11.7: Boat Selection
11.7.1
The boats to be used for each event shall be selected by the Chief of Competition, the Tournament Chairman and the Tournament Technical Controller in such a manner as they may determine from among those made available by the organizers.
11.7.2
For jumping and slalom, identical boats shall be used by each competitor within a division in an event. In the trick event, the skier may have the option of the boats made available for the event.
11.7.3
The driver and/or the boat can be changed by the Chief of Competition if he/she deems it necessary. The Chief of Competition may also decide to use alternating identical boats to reduce lost time and to speed up the running of the eventÑthis only if the tournament site and the competition areas are suited for two boats.
11.8: Ski Width
Maximum ski width shall not exceed 30 percent of ski length.
11.9: Ski Bindings
Any type of fixed foot bindings may be used.
11.10: Ski Fins
Any type of fixed fins may be used.
11.11: Other Ski Devices
No other devices are permitted
11.12: Tow Line Specifications
11.12.1
The Tournament Committee shall furnish single-handle, 23 m and 18.25 m low lines constructed as outlined below, made of 6 mm, single braided, monofilament line of plastic material, with the handles and lines meeting the following specifications:
- Number of strands: 12
- Number of yarns each strand: 60
- Diameter at 5.5 kg load: 6.3mm
- Weight per meter: 16.0 g to 18.5 g
- Breaking load, minimum: 590 kg
- Elongation at 115 kg tensile load: 3.2% (maximum): The gauge length
shall be set at 5.5 kg tensile load
- All measurements of tow lines shall be made under 20 kg tension
and shall be made between the following points as applicable:
(1) the centre line of the handle;
(2) the inside surface, furthest from the handle of
any attaching loop.
11.12.2
The tow lines may be made in one section or alternatively in tow sections consisting of a single line 21.5 m long for jumping, and 16.75 m long for slalom, and a handle portion 1.5 m long. Multi-segment slalom lines may be used. The segments shall be coloured in the same sequence as the loops shown in 11.14.
11.12.3
Splices shall be 15 cm (minimum) long secured with tucks before and/or after the splice, or knotted to prevent slipping.
11.13: Handle Specifications
The handle shall be made of 2.50 to 2.80 cm outside diameter material with no sharp edges or projections, with unpainted wood or other non-slip surface or coating and capable of floating. The handle shall be attached to the rope so that it is perpendicular to the direction of the line. The handle measurements specified in 11.14 is the end-to-end length of the handle. The attaching rope must, in all cases, go through the handle and must be attached so there is no possibility of movement between the rope and handle when in use. The minimum certified breaking load of the handle shall be 270 kg applied at the rate of 270 kg per minute, at two load points 9 cm apart at the centre of the handle with the ends supported at the rope holes.
11.14: Tow Lines
11.14.1
Slalom Tow Line: The tow lines to be used for slalom shall have loops spliced into the line at distances from the handle of 16 meters, 14.25 meters, 13 meters, 12 meters, 11.25 meters, and 10.75 meters. A tolerance of plus or minus 15 cm on the distance from the loop to the handle is allowed for rope lengths at 18.25 m and 14.25 m. From the 13 m rope length and on, this tolerance is reduced to plus or minus 7.5 cm.
11.14.2: Jump Handle
11.14.3
Trick Tow Line: The contestant must furnish his/her own line and handle for the trick event, of any reasonable length and material, restricted only by safety considerations.
11.15: Shock Tube Tow Lines
All tow lines should employ a shock tube for safety purposes.
11.16: Skier Supplied Handles for Slalom and Jumping
For slalom and jumping, contestants may furnish their own handle to attach to the tournament lines, providing they notify the starter at the dock at least three skiers listed on the starting list before their turn, of their wish to change handles. The handle may be of any material. The length of the handle attachment, measured from the inside surface of the attaching loops furthest from the handle to the centre of the portion of the handle furthest from the attaching loop, must be 1.50m -/+ 2.5 cm.
11.17: Jump Ramp Specifications
The jump ramp shall be an inclined plane with an apron on the right-hand side. The ramp shall meet the following specifications:
11.17.1
Width: 3.70 to 4.30 meters at all points (4.25 meters recommended)
11.17.2
Length out of water: 6.40 to 6.70 meters at all points
11.17.3
Length under water: 100 cm minimum
- .275, .255, or .235 (+.003) for Open Men and Men I at the skier's option
- .255, or .235 (+ .003) for Men II at the skier's option
- .235 (+ .003) for all other divisions
Ratios are to be computed on both sides of the ramp, and ramp height at the take-off edge at the two corners may differ no more than 2.5 cm. (See Diagram 4 following the Appendices of this Rule Book)
11.17.5
The surface must be flat with a maximum deviation of 2.5 cm from a plane.
11.17.6
An apron shall extend the full length of the ramp on the right-hand side and be at least 30 cm under water when the ramp is set at the .275 ratio. The jump apron should have a minimum angle of 28 degrees from perpendicular and a maximum angle of 50 degrees. The recommended angle is 45 degrees.
11.17.7
Markings of 6.40 and 6.70 in length, clearly identified, shall be placed on the apron and/or ramp surfaces so that they are readily visible.
11.17.8
A vertical line visible from shore shall be painted at the centre of and just below the take-off edge for meter sighting purposes.
11.17.9
The jump ramp must be securely anchored in place so that the centre take-off edge will not vary more than the sighted width of the sight line on all meters after coming to static rest. ÒStatic restÓ is the position assumed by the ramp in ambient water not affected by boat wakes, skiers' wakes, or backwash.
11.17.10
The jump ramp shall be equipped with a watering system sufficient to ensure that the surface of the ramp is continually wet.
11.17.11
All measurements of the ramp shall be made under tournament conditions, including the weight of water equipment or of a water person, and not including the weight of a skier.
11.17.12
Ramp aprons shall be of a different colour or shade from the ramp surface so as to provide a satisfactory contrast between apron, water and jump surface.
11.17.13
The jump ramp must be set between parallel to the course and at an angle open from parallel not exceeding 5 degrees. ' Open' refers to the movement of the lower end of the ramp towards the jump course guide buoys. An angle of 5 degrees open from parallel approximates a distance of 57 cm.
11.18: Slalom Towers
11.18.1
The slalom judging towers shall be braced structures having a platform not less than 3 m above the water surface with railings. They may either rest on the bottom or be securely fixed in position. The use of two slalom judging towers is mandatory.
11.18.2
The two slalom towers "A" and "B" shall be located in the following approximate positions:
"A"- between ball 1 and ball 2 and on the same side as ball 1 in a suitable position to view the skier's path through the adjacent entrance/exit gate.
"B"- between ball 5 and ball 6 and on the same side as ball 6 in a suitable position to view the skier's path through the adjacent entrance/exit gate.
11.19: Buoys
General
11.19.1
Colour of buoys shall be selected for maximum visibility. A fluorescent yellow or red is recommended.
11.19.2
Guide buoys used within the slalom course shall be a different colour from the gate and slalom buoys used by the skiers. The guide buoys used by the timer for the intermediate times (see Rule 15.7) shall be a different colour from the other guide buoys.
11.19.3
Spherical guide buoys shall be a minimum of 22 cm in diameter. However it is strongly recommended that cylindrical or rectangular solid buoys be used as guide buoys in the slalom course or in the jump course with the following restrictions:
a) The buoy shall be fastened so that at least 15 cm but not more than 30 cm of the buoy is above the water line. They shall appear vertical.
b) The buoy shall have a maximum cross sectional area of 194 sq. cm. (30 sq. inches) and a minimum cross sectional area of 75 sq. cm (12 sq. inches). This allows a rectangular solid of 5 x 6 inches or cylinder of 6 inches in diameter.
c) The buoys shall be fastened so that the distance between the inside edges of the two buoys (boat tunnel width) shall be 2.05 m +/-15 cm (1.9m - 2.2m).
11.19.4
Slalom buoys shall be 22 to 28 cm in diameter (23 cm recommended). Gate buoys shall be 25 to 35 cm (27 cm recommended). These buoys shall also be generally spherical above the water line.
11.19.5
Slalom buoys shall be of a light-weight pliable material with smooth exposed surface.
11.19.6
Each buoy shall have a strong loop for attaching anchor lines. The buoys must be attached to the anchor line by the use of a system that will tighten the buoy in such a way as to ensure that it retains its original position.
11.19.7
Slalom buoys shall be fastened so that they have 11-17 cm of height out of water (11.5 cm recommended). The entrance and exit gates and boat guide buoys shall be fastened so that they have 16-22 cm of height out of the water (17 cm recommended).
11.19.8
Jump course buoy E may be sunk below 16 cm height out of water, however, it must be clearly visible.