An open boat when fully loaded shall have sufficient buoyancy
to be able to remain afloat and should have a positive metacentric
height, that is, the vessel returns to the upright when a heeling
moment is applied and removed, when totally flooded. The open boat
shall be deemed by the Administration to have sufficient buoyancy
by practical test or where detailed calculations are confirmed to
show that the buoyancy of the vessel is greater than the total weight
of the vessel and its load.