OICNW-1-5C

Determine magnetic compass deviation

Function: Navigation at the operational level

Competence Knowledge, Understanding & Proficiency Task

Plan and conduct a passage and determine position

A1.07 Ability to determine errors of the magnetic and gyro-compasses, using celestial and terrestrial means, and to allow for such errors

Determine magnetic compass deviation

Assessed in: MT-4133 Bridge Resource Management

Condition

On a ship underway or a full mission ship simulator, using navigational or natural terrestrial ranges, using only a magnetic compass, and a chart with variation.

Behavior

Note the vessel's magnetic compass heading while aligned on the range and determine magnetic compass deviation.

Standard

  1. The magnetic heading is compared to the charted range bearing.
  2. The magnetic compass error is determined and properly labeled.
  3. Variation is determined from the chart.
  4. The deviation solution is ± 1° of the assessor’s solution.
  5. The deviation is correctly recorded in the compass record book.