Missed: An Opportunity 52 Years Ago to Do Differential Doppler Over a 4200 nm Baseline
In the mid-1960s, there was a “war” between Naval Reactors (NR) and Naval Intelligence (ONI) over the speed capabilities of the NOVEMBER Class Soviet SSN.
Based on NR's assessment that the Soviets were not technologically capable of building a nuclear submarine that exceeded the capabilities of NAUTILUS, ONI was directed to publish 22 knots and 15,000 shp for the NOVEMBER even though the acoustic data indicated 30 knots.
We knew then the maximum shaft rpm for the NOVEMBER; the uncertainty was the turns-per-knot (TPK) value about which there was conflicting information.
What would have nailed the TPK value then was an opportunity not exploited: simultaneous detection bow and stern by arrays separated by 4200 nm. The TPK value that could have been derived from that differential Doppler solution would have been an order of magnitude more accurate than then existing estimates.
The “war” would have entered a new phase; however, the result would probably been the same: 22 knots and 15,000 shp. Now, of course – as previously discussed - we know the answer was 29-30 knots and 37,000 shp. This was the typical Soviet approach: brute force.