There is an experimental tow pack that can be deployed that sets behind about 2500 yds that allows remoted fiber link periscope views, infrasound sonar and passive RX, ESM and AA launch. The array is useable to 12 knots max. The onboard noisemaker if activated can serve as decoy for 30 minutes autonomously. Beats using the Sail sensor systems and in conjunction provides highly accurate ranging using infrared lasers.
If cut loose the tow pack is recoverable within a limited time but will self sink and destruct vital items after a set time.
The game has all manner of innovations, yet to fielded.