Probably. No-one's allowed to talk about this stuff but the Walkers. So I guess we're left with inference, but, anyway, the picture of Barracuda, above, not made available through Time, shows us what the first generation of passive sonar derived from BALKON entailed in the spring of 1951. It's like Barracuda is pushing a pulpit. There's also an active sonar dome, BQR-2, below the waterline. The monster on the bow is the BQR-4 array, proven in trials to be able to detect a snorkeling submarine at 30 nautical miles distance, which would allow loitering K-boats to engage Soviet submarines passing through port approaches and narrow channels, on the surface or snorkeling. Given that the only realistic way for the Reds to deploy their entirely imaginary fleet of knockoff, mass-produced XXIskis was down the Baltic, it actually sounds a lot more practical than the heavy woe-is-us sighing about the K-boat would lead one to think. However, the complaining quickly led from the K-boats to the bigger, more expensive and more capable Tang class.