What does an "overturned" condition indicate about a vessel's stability?

An "overturned" condition signifies that a vessel has heeled to an angle that exceeds its capacity to right itself. This situation occurs when the heeling angle surpasses a critical point, often defined by the vessel's metacentric height and center of gravity, resulting in a loss of stability. In practical terms, once a vessel is overturned, it cannot return to an upright position and usually capsizes, leading to hazardous circumstances for the crew and the vessel itself.

In contrast, the other options describe states of stability or balance that do not reflect the severity of an overturned situation. A stable and upright condition suggests that the vessel is well within its stability limits, while a momentary tilt may imply temporary changes in orientation without jeopardizing the vessel's stability. Lastly, achieving a state of balance during rough conditions acknowledges the ship's ability to handle adverse weather but does not pertain to an overturned scenario, where balance is entirely compromised.