Characteristics/Acoustic Detectability of the Russian VA-111 Shkval Rocket-Powered Torpedo
By Bruce Rule - Sep 30, 2016
Open sources indicate the Russian VA-111 Shkval rocket-powered torpedo - which uses bubble-screen technology to achieve speeds of 200 knots (100m/s) - is 8.2m long, has a diameter of 533mm, weighs 2,700kg and is capable of carrying a 210kg (460 lb) warhead.
The torpedo can hit targets at ranges from 7,000m (7650 yds) to 13,000m (14,220 yds).
At 200 knots, the run-time (rocket burn-time) to a range of 7650 yards is 68 seconds; to 14,220 yds, 126 seconds. (Not much time to take evasive action!)
Judging from the acoustic detectability of the R-21/D4 missiles - that fired to fuel-exhaustion within the breached pressure-hull of the GOLF-II Class Russian SSB K-129 - by sea-floor sensors, a VA-111 should be detectable by SOSUS at ranges in excess of 1000 nautical miles as a high-level of broadband energy below 50 Hz with no unique frequency content. (At ranges to which the VA-111 is fired, it could be detected through the hull of the intended target.)
For detailed discussions/illustrations of the acoustic detections of the K-129 missile-firing events, read "PROJECT AZORIAN, THE CIA AND THE RAISING OF THE K-129" by Norman Polmar and Michael White, pages 162-167.