Leeway allowance in plotting

Bowditch Ch. 23 §2301

Bowditch Ch. 23 §2301 — Navigational Errors Navigational errors arise from instrument error, observation error, plotting error, computation error, and the basic assumption that the vessel has held the planned course. Cumulative errors must be checked against fixes whenever possible.

Bowditch Ch. 7 §702

Bowditch Ch. 7 §702 — Bearings and Lines of Position A running fix is a fix obtained when LOPs cannot be taken simultaneously. The first LOP is advanced along the DR track to the time of the second observation; the intersection is the running fix, less accurate than a fix from simultaneous LOPs.

33 CFR §164.38

§ 164.38 § 164.38 Automatic radar plotting aids (ARPA). (a) The following definitions are used in this section— means material in any quantity that is shipped, stored, or handled without benefit of package, label, mark or count and carried in integral or fixed independent tanks. means a stage of construction where— (1) The keel is laid; (2) Construction identifiable with a specific ship begins; or (3) Assembly of that ship has commenced comprising at least 50 tons or 1 percent of the estimated mass of all structural material, whichever is less. means— (1) A flammable liquid as defined in 46 CFR 30.10-22 or a combustible liquid as defined in 46 CFR 30.10-15; (2) A material listed in table 151.05 of 46 CFR 151.05, table 1 of 46 CFR 153, or table 4 of 46 CFR Part 154; or (3) A liqui…

33 CFR §164.40

§ 164.40 § 164.40 Devices to indicate speed and distance. (a) Each vessel required to be fitted with an Automatic Radar Plotting Aid (ARPA) under § 164.38 of this part must be fitted with a device to indicate speed and distance of the vessel either through the water or over the ground. (b) The device must meet the following specifications: (1) The display must be easily readable on the bridge by day or night. (2) Errors in the indicated speed, when the vessel is operating free from shallow water effect, and from the effects of wind, current, and tide, should not exceed 5 percent of the speed of the vessel, or 0.5 knot, whichever is greater. (3) Errors in the indicated distance run, when the vessel is operating free from shallow water effect, and from the effects of wind, current, and …

33 CFR §83.10

§ 83.10 § 83.10 Traffic separation schemes (Rule 10). (a) This Rule applies to traffic separation schemes and does not relieve any vessel of her obligation under any other Rule in subchapter E. (b) A vessel using a traffic separation scheme shall: (i) Proceed in the appropriate traffic lane in the general direction of traffic flow for that lane; (ii) So far as practicable keep clear of a traffic separation line or separation zone; (iii) Normally join or leave a traffic lane at the termination of the lane, but when joining or leaving from either side shall do so at as small an angle to the general direction of traffic flow as practicable. (c) A vessel shall, so far as practicable, avoid crossing traffic lanes but if obliged to do so shall cross on a heading as nearly as practicable at…

33 CFR §83.34

§ 83.34 § 83.34 Maneuvering and warning signals (Rule 34). (a) When power-driven vessels are in sight of one another and meeting or crossing at a distance within half a mile of each other, each vessel underway, when maneuvering as authorized or required by these Rules: (i) Shall indicate that maneuver by the following signals on her whistle: (1) One short blast to mean “I intend to leave you on my port side”; (2) Two short blasts to mean “I intend to leave you on my starboard side”; and (3) Three short blasts to mean “I am operating astern propulsion”. (ii) Upon hearing the one or two blast signal of the other shall, if in agreement, sound the same whistle signal and take the steps necessary to effect a safe passing. If, however, from any cause, the vessel doubts the safety of the pr…