TMA and range determination

[Troels K]

Hi

I’m new to Dangerous waters.

I’m having some difficulties determining the correct range to a contact.

At the moment I’m using active sonar to find the range. However, it would be nice if the range could be found without active sonar.

Therefore, how do you guys determine a suitable range to a possible target?

I know the basic TMA like lead/lag course, but the manual says that two or tree legs will result in a single possible solution (page 5-22), these two or tree maneuvers confuses me.

This is probably a huge subject, however, some short guidelines would also be appreciated.

Thanks in advance.

Troels