re: #139 Love-Child of Cassandra and Sisyphus

The density of living things that swim in the sea is close to that of seawater. Makes sonar detection difficult.

OTOH, if it was an uncharted seamount then that should have had decent returns on the sonar.

Active sonar is very seldom used (think SILENT SERVICE). Though secure fathometers are used constantly. If it was an uncharted seamount. Someone in the sonar room is fucked for not monitoring it.