Squeezing Still More From Acoustic Data on the Condition of the SCORPION Wreck
By Bruce Rule - Mar 26, 2017
Invalidation of the assumption that the initial compression and expansion (rebound) phases of the collapse of a submarine pressure-hull at great depth are symmetrical (of equal duration), and measurement of the acoustic signal (bubble-pulse) created by the collapse-expansion cycle of air within the SCORPION pressure-hull indicate SCORPION collapsed (complete destruction: fragmentation/compression) in one-fifth of the reciprocal of the bubble-pulse frequencies of 4.46 Hz or in 0.037 seconds.
Temporal asymmetry exists between the compression and expansion phases of submarine pressure-hull collapse events because the duration of the collapse phase is truncated by the collapse phase pressure wave encountering the compacting mass of the hull and internal structures whereas the expansion (rebound) phase terminates less abruptly when the falling pressure of that expanding wave and its momentum are overcome by the ambient pressure at the collapse depth.
During the 0.037s (37 millisecond) duration of the compression phase of the SCORPION collapse event, two after compartments were symmetrically “telescoped” (one within the other) a distance of about 50-feet. Those time and distance values require an average velocity for the forward moving hull sections of about 900 mph, three times a previously estimated value which was based on the assumption that the durations of the compression and expansion phases were equal.
It was this enormous axially-aligned forward vector - opposed (primarily) by inertial forces (a body at rest tends to stay at rest) acting on both the shaft and the propeller, and (secondarily) by the resistance of the water acting on the effective blade area of the propeller that tore the shaft - with the propeller still attached - from the thrust block and out of the submarine where it fell separately to the bottom to be imaged near the telescoped after hull sections by the US submersible TRIESTE. Imagery also showed the retention flange of the shaft was separated from the body of the shaft.
This assessment - based on acoustic data - resolves the long-standing and often contentious issue: was loss of the propeller shaft the cause of the USS SCORPION disaster or the result?