Mate*

They know a sub is operating in that area

*Intelligence*

To preserve fuel

Transit speed is the most efficient speed

moot point

Thats the point of it

Not for fuel economy?

Not for detection radius?

When you are at transit speed like 15 knots or so

You are at the most efficient

thats why its transit speed

Thats the range quoted on all ships

Maximum range at most efficient speed which is..transit speed

You would only slow down from transit if you heard something or if you were scared of a sub about

IOf you heard something they know you're there already

youre fucked

Which certainly they would be aware of from intelligence

If your just slowly

Well you better think of everything else that makes a surface ship loud

Undamped pumps

People talking

People moving

Water flowing in the shi

Air con fans and condensers

I'm not denying warships and ships in general are loud

A sub has designed these things almost out

ALMOST

EVERYTHING is detectable..

By some means or another

Read

ALMOST

That's not in doubt here.

Thanks

So yeah

A surface ship is only detecting a sub first in a very limited number of circumstances

And they all require the sub to either be old as shit or incompetent as fuck

Or any combination thereof

As most subs are

*old*

There you have to remember that most surface passive sonar systems are less effective then their sub surface counterparts