USCG Exam PracticePassing distance and CPA from chart plot
A vessel required to carry ARPA under 33 CFR §164.38 must also be fitted with a speed and distance device. Under what operating conditions must the device's speed error not exceed 5 percent of vessel speed or 0.5 knot, whichever is greater?
- A. When operating at speeds above 5 knots in open ocean conditions
- B. Under all operating conditions, including shallow water and adverse current
- C. When operating in water depths greater than twice the vessel's draft
- ✓ When operating free from shallow water effect and from the effects of wind, current, and tideCorrect
Why D is correct
33 CFR §164.40(b)(2) specifies that the 5-percent-or-0.5-knot speed error tolerance applies when the vessel is operating free from shallow water effect and from the effects of wind, current, and tide. The regulation does not specify a minimum speed or a depth-to-draft ratio as the qualifying condition.
Cited:33 CFR §164.40