Calvert's "Silent Running"

[Rockin Robbins]

The key words must be "all but." Unlike our game, they had selective listening abilities, from the lower end of the listening range to the supersonic. Therefore, contacts could be developed on the surface and they were expected to be so. The Sonar Operator's Manual makes it clear that the sonar operator is expected to stay on duty while surfaced until ordered to stand down.

In addition, the range of filters, not available in the game, made this possible. Own ship sounds were lower frequencies, listened to by selecting the bass boost filter. To filter out own ship sounds, filters above 500 cps were used. (no Hertz back then, it was cycles per second). There were two filters available for frequencies above that, even, so it is clear that sonic sonar was useful when surfaced. Supersonic sonar would not have cared much about ownship noises at all.

Here's the illustration in the sonar manual about using filters with normal sonic passive sonar.



From the manual:

Filters can define and narrow the target
Propeller noise is made up of all frequencies. But background noise, from the water and the submarine, is mostly low-frequency sounds. Therefore, by operating with a high-frequency filter you can get rid of the background noise, yet still hear the screws.

BUT, in my search of all reported surface contacts developed by all submarines during the war, I did not find a single instance where the FIRST contact was made through sonar. Obviously visual and radar was superior there, but after contact was made, oftentimes sonar was put to use, even on the surface.

Sonar is one of Silent Hunter's weaknesses, with plenty of room for more realism and detail. There were three main sonar arrays, with filters and amplifiers for each, none of which is modeled. This could be a fascinating addition to future sub sims. Unfortunately, it looks like SH5 ain't it.

[DigitalAura]

Wow...that's some amazing clarity given, RR. I had no idea the SH4 sim was so off the mark! I'm somewhat disappointed to learn that the way I hunt has no similarities to reality.
I use sonar while traveling on the surface (at standard speed) to find convoys (I have no SJ yet)... and in this book, Calvert claims they ran on the surface and relied on the high periscope for extra visual range to spot convoys.

I thought I'd pick up some cool tips from reading this book, but now I'm finding this game is becoming less and less a realistic sim altogether.

[DigitalAura]

Originally Posted by Rockin Robbins

I did not find a single instance where the FIRST contact was made through sonar.

Calvert claims that on many occasions they made contact through the sonar...that is to say, they HEARD the enemy pinging away which resulted in giving away the task force's location. (perhaps you don't consider this a FIRST CONTACT because there isn't anything to create a solution yet?)