DN Specifications
D. Boom
IDNIYRA OFFICIAL SPECIFICATIONS
REVISED MAY 2022
Note: Dimensions are given in inches in the English System (except as noted) and in millimeters (MM) in the metric system.
| D. Boom | English | Metric | ||
| Max | Min | Max | Min | |
| 1. Length (from mast): | 108 | Opt | 2743 | Opt |
| 2. Depth (from outhaul bracket to 12”, 305mm from, mast): | 3 | 2-1/2 | 76.2 | 63.6 |
| 3. Thickness (from outhaul bracket to 12”,305mm from mast): | 1-25/32 | 1-1/4 | 45.25 | 31.8 |
4. Only one boltrope tunnel is permitted. The boltrope tunnel shall be substantially straight with boom relaxed. An aluminum boltrope tube is allowed. It must weigh less than three ounces per foot (280 grams/meter). The internal diameter must be at least 3/8’’ (9.5mm). The cross section of the tube is optional.
5. Cross section profile is optional. Boom may be hollow.
6. Boom jaws are optional. Devices which prevent or hinder movement of the boom on the mast are prohibited except for check wire.
7. A 1/2’’ (12. mm) wide stripe shall be painted around the boom in contrasting color. Stripe shall be perpendicular to sail tunnel. Forward edge of the stripe shall be 8’ 10’’ (2692 mm) or less from forward inner surface of mast sail slot projected fairly.
8. Boom shall be constructed of wood or aluminum. Fiberglass may be added for reinforcement only
INTERPRETATIONS OF THE OFFICIAL SPECIFICATIONS BY THE TECHNICAL COMMITTEE
Effective May 31, 2020
D. Boom
01/01/79: The boom jaw may not have a projection on the bearing surface that will fit into the mast slot and thereby affect the rotation of the mast.