Originally Posted by
Ninthace
Surely passive sonar will give you a bearing but not a range unless different sensors are combined (unless the SM is close enough to be in trail). Satellite imagery is intermittent, the claim was that the precise whereabouts was known at all times. Likewise, I would have thought ELINT and radar woud require a shadow vessel to provide reliable data.
Seems possible that the Doppler could be processed along with a bearing from a passive sonar array to give a track perhaps? I don't know enough about sonar but remember seeing waterfall displays showing the frequency shift as a target moved relative to the sensors. No idea how this can be processed though.