How about a situation when the SSBN needs to run away from a pursuing enemy SSN? Of course this is needed only if the unthinkable happens, but if things got to that point the SSBN needs every ounce of advantage it can get to survive long enough to launch it's SLBMs.
The SSN would be at most, 15knots faster than the SSBN.
Based on the ADCAP torpedo specifications, the SSN would need to get to within 10nm? for the ADCAP to hit an SSBN directly running away.
But the SSBN could launch torpedoes backwards at the noisy SSN. And the SSN is running directly into the path of the torpedo.
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I'm not against a SSBN being of a sailless design. But shouldn't they test out the sailless SSN design first, before deciding to use it on an SSBN?