- Diameter of the sheaves of the sheet blocks shall not exceed 4'' (101.6 mm).
- Two of the six required blocks may incorporate a one-way feature.
- Steering chock may incorporate a shock-absorbing feature.
- Hardware need not conform to plans as long as specifications are not violated and hardware performs the same function that the plan item performs.
- English MetricSide Chock
Max Min Max Min
- 1-3/32 31/32 27.7 24.7 Width of runner slot at the smallest dimension where the chocks come in contact with the runner's side or stiffening element:
- 3-1/2 2-7/8 88.9 73.1 Depth of chock:
- 9 6-3/4 228 172 Length of chock:
- 4-3/4 ---- 121 ---- Width of chock:
- 1-5/8 1-1/8 41.0 28.6 Mast Step -Height of pivoting point (center of ball) above deck.
- Location of Halyard catch on mast is optional.
- Halyard must be capable of lowering and raising the sail with yacht in upright position.
- Additional fittings to secure halyard to mast are permissible.
- Only one mast, boom, fuselage, and runner plank may be used for an entire regatta, unless broken beyond reasonable repair (as interpreted by the Race Committee).
- An adjustable footrest may be used.
- A device may be placed in the back of the chock to prevent the front of the runner from tipping downwards. The device may not contact the runner when all three runners are on the ice.
- The side chock and the steering chock shall be made of steel, stainless steel or aluminum.
- English MetricBow Tang
Max Min Max Min
- 3-3/4 ---- 95.3 ---- Width:
- 8 ---- 203.2 ---- Horizontal distance from the pivot axis of the steering runner to the aftermost end of the bow tang:
- 3 ---- 76.2 ---- Height above a horizontal line extending forward from the deck at a point 2” (50.8 mm) behind the bow:
- Runner Plank
- The runner plank mounting system shall not extend more than 4” (101.6 mm) outside of the side panel of the fuselage.
- The runner plank mounting system shall be located in an area that does not exceed 30” in the fore and aft dimension.
- Bobstay Strut,
including Mounting Hardware
- ---- 3 ---- 76.2 Height: (from bottom skin of fuselage)
- 6 ---- 152.4 ---- Length:
- 4 ---- 101.6 ---- Width:
- Mast Step
- 9 ---- 228.6 ---- Length:
- 3 ---- 76.2 ---- Width:
See Fittings Interpretations at the end of the Specifications.