What is a genuine limitation of a bow thruster that's worth understanding before relying on one for close-quarters manoeuvring?

A. Bow thrusters have no real limitations and can fully replace conventional boat-handling skills

B. A bow thruster loses effectiveness at higher boat speeds (the thrust becomes a much smaller fraction of the forces already acting on the hull), and most are only rated for short bursts of use rather than continuous operation — treating it as a substitute for understanding wind, current, and prop-walk, rather than a helpful supplement, is a common mistake

C. Bow thrusters work equally well regardless of boat speed

D. Bow thrusters can be run continuously for as long as needed with no practical limitation

A. Nothing — a test lift can proceed immediately after repairs

B. Testing should wait until cargo operations begin

C. The area within the grab's swing radius should be cleared of personnel before the lift

D. Only the crane operator needs to be aware the lift is happening

A. Who must remain clear of the exclusion zone while the lift takes place

B. The lunch schedule for the deck team

C. Only the weather forecast for the next watch

D. The cargo manifest for the next port