USCG Exam PracticeRadar fundamentals and ARPA basics
A vessel required to carry ARPA under 33 CFR §164.38 must also be fitted with a speed and distance device under 33 CFR §164.40. Which tolerance is specified for indicated speed error when the vessel is free from shallow water, wind, current, and tide effects?
- A. Not to exceed 2 percent of vessel speed or 0.2 knot, whichever is greater
- ✓ Not to exceed 5 percent of vessel speed or 0.5 knot, whichever is greaterCorrect
- C. Not to exceed 5 percent of vessel speed or 1.0 knot, whichever is greater
- D. Not to exceed 10 percent of vessel speed or 0.5 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, under the stated free-running conditions.
Cited:33 CFR §164.40