Oh course there are sailors who know their flags
.... if I see Zulu, I know to re-start and taking a scoring penalty for being in the triangle during the minute before the start.... grin.
Exotica...no doubt people will respond immediately to these:
NK There is not sufficient depth
NT 6 What is your maximum draft
JJ My maximum draft
when I went aground was (number feet or meters)
OS 1 You should keep a lookout for mines
OW There is a minefield ahead of you.
You should stop your vessel and wait for instructions
PQ 1 You should keep further away from the coast
NE You should proceed with great caution .
NE 1 You should proceed with great caution; the coast is dangerous.
NE 5 You should proceed with great caution; hostile vessel sighted (in lat… long…)
RY You should proceed at slow speed when passing me
(or vessels making this signal)
UV 7 Having disregarded our request for compliance with the
conditions of innocent passage
through the territorial sea,
you are required to leave the territorial sea immediately
and perhaps my favorite:
SN You should stop immediately. Do not scuttle.
Do not lower boats. Do not use the wireless.
If you disobey I shall open fire on you.