Running fix from a single object

Bowditch Ch. 13 §1301

Bowditch Ch. 13 §1301 — Radar Navigation Marine radar transmits microwave pulses and processes the echoes to display a plan-view picture of surrounding targets. Range and bearing to a target give a direct fix.

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 §701

Bowditch Ch. 7 §701 — Bearings and Lines of Position A line of position (LOP) is a line along which the vessel is known to lie at a given moment based on a single observation. A fix is the intersection of two or more LOPs taken simultaneously.

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.

Bowditch Ch. 7 §703

Bowditch Ch. 7 §703 — Bearings and Lines of Position Bearings to a single object can produce a running fix when the relative bearing changes substantially. The 'doubling-the-angle' technique uses two relative bearings; the distance run between them equals the distance to the object at the second bearing.

46 CFR §176.710

§ 176.710 § 176.710 Inspection and testing prior to hot work. (a) An inspection for flammable or combustible gases must be conducted by a certified marine chemist or other person authorized by the cognizant OCMI in accordance with the provisions of NFPA 306 (incorporated by reference, see 46 CFR 175.600) before alterations, repairs, or other operations involving riveting, welding, burning, or other fire producing actions may be made aboard a vessel: (1) Within or on the boundaries of fuel tanks; or (2) To pipelines, heating coils, pumps, fittings, or other appurtenances connected to fuel tanks. (b) An inspection required by paragraph (a) of this section must be conducted as required by this paragraph. (1) In ports or places in the United States or its territories and possessions, the …