USCG Exam PracticeGPS and electronic navigation
A vessel is transiting a narrow channel with minimal underkeel clearance. Under 33 CFR §164.11, the person directing the vessel's movement must consider which specific hydrodynamic effect when setting speed?
- A. The tendency of the vessel to yaw when running before a following sea
- ✓ The tendency of the vessel to squat and suffer impairment of maneuverabilityCorrect
- C. The tendency of the vessel to develop increased metacentric height at speed
- D. The tendency of the vessel to experience reduced propeller efficiency in shallow water
Why B is correct
33 CFR §164.11(p)(3) specifically identifies the tendency of the vessel underway to squat and suffer impairment of maneuverability when there is small underkeel clearance as a required speed consideration. Squat is the hydrodynamic phenomenon by which a vessel's bow and stern sink closer to the bottom as speed increases in shallow water.
Cited:33 CFR §164.11