While going full ahead with a right hand prop, what happens if the engines are placed astern with hard left rudder?

When a vessel is moving full ahead with a right-hand propeller and the engines are placed astern while applying hard left rudder, the dynamics of the vessel's movement come into play. The right-hand propeller typically creates a turning tendency that causes the stern to swing to the side opposite of the propeller's rotation—in this case, to starboard. When the engines are placed astern, the propeller pushes water in the opposite direction, which changes the forces acting on the hull.

Applying hard left rudder while the vessel's propulsion is reversed amplifies this effect. The stern will initially respond to the rudder and the reverse thrust by swinging to starboard because the reverse thrust from a right-hand propeller causes a stronger turning moment in that direction. After that initial swing to starboard, the vessel's increased rotational momentum and the rudder's influence can cause the stern to then swing back to port.

This sequence illustrates how the combination of engine thrust, propeller rotation, and rudder input influences the turning dynamics of the vessel. Understanding this behavior is crucial for effective maneuvering, which is why the answer accurately describes the expected response of the vessel under these circumstances.