USCG Exam PracticeLeeway allowance in plotting
A vessel equipped with an ARPA as required by 33 CFR §164.38 must also be fitted with a speed and distance device under 33 CFR §164.40. The allowable speed error for that device, when operating free from shallow water effect and environmental influences, shall not exceed:
- A. 1 percent of vessel speed or 0.1 knot, whichever is greater
- ✓ 5 percent of vessel speed or 0.5 knot, whichever is greaterCorrect
- C. 5 percent of vessel speed or 0.5 knot, whichever is less
- D. 10 percent of vessel speed or 1.0 knot, whichever is greater
Why B is correct
33 CFR §164.40(b)(2) specifies that speed errors should not exceed 5 percent of the speed of the vessel or 0.5 knot, whichever is greater. Option C uses the same numbers but applies the wrong comparative operator; the regulation specifies whichever is greater, not whichever is less.
Cited:33 CFR §164.40