Tracking Active Sonar Contacts

[Destex]

Originally Posted by Mob1us0ne

I'm a former USAF ECM troop and can confirm the bit about accurate bearings from RWR and I'm sure the RX mode on a sub or sea based ESM mast uses the same method of operation. Bearing info is highly accurate, it has to be as the operator needs to inform the vehicle commander threat direction for evasion.

Hi Mob1us0ne, and welcome.
No one claimed it's not possible to analyze accurate bearing to electromagnetic transmissions. However, Ground or aerial ECM systems are not relevant as the technological challenge in a submarine is different.

First, as Harpoon says, there's a single mast.
Second, that mast is small and can't contain a lot of nodes which are necessary for signal strength interpolation - the basis of bearing measurement. As much as the nodes are fewer and smaller the bearing analysis is less accurate.

Aerial systems have the luxury of size, number of nodes and different locations on a rather large body in comparison. Try to cram all that into a tiny tiny sub mast, there will be several compromises, bearing accuracy being the first casualty. Also, on aircraft the fast self movement can be used to some extent (just a theory, I don't know for sure if indeed it is), another aspect lacking in submarines.

Therefore, at least up to the 80's if not later than that, submarine ESM systems could not provide accurate enough bearing measurements that can be used for reliable passive TMA calculations.