“One boat is obvious astern of A further when her hull and devices in standard position are driving a line abeam within the aftermost level of the opposite boat’s hull and machines in regular placement. The opposite boat is evident in advance. They overlap when neither is evident astern. [snip] https://www.whofish.org/Default.aspx?tabid=45&modid=379&action=detail&itemid=310505&rCode=18