SUBSIM Radio Room Forums - View Single Post - SH4 Hydrophone firing solution with US Boats?

Bothersome · 12-01-13, 09:45 PM

There was a purely hydrophone targeting method posted in the SH4 section on SubSim several years ago. I don't have it book marked or anything. A search might turn up something.

Basically, it involved taking 4 bearings and precise time intervals and drawing a straight line through those bearings that would be equally spaced. That is IF the ship didn't change course and didn't change speed.

I've pulled off many a torpedo shots in heavy fog and rain. But I used the radar to get the target's heading and speed. I use a method of distance traveled / elapsed seconds * 1.8 = knots.

Then I would line up on a 90 degree perpendicular to the targets heading and set up my TDC computer for the distance, AoB, and speed settings to cross at either 225 or 45 depending if it's coming in from my port or starboard side. I would engage the TDC computer at the time the sonar reading crossed my preset bearing. In fact I tend to use this method even on clear days because I don't want to take a chance on the enemy spotting my periscope. Then I'd simply open doors and fire after. Of course I already had the depth and speed of the torpedoes already set by then. If you're only about 1000 yards away from the targets path, you just about can't miss.

The US side is very tough to set up for multiple targets, unlike the German U-Boat side.

Sorry I couldn't be more help for the full sonar method though.

12-01-13, 09:45 PM	#2
Bothersome Planesman Join Date: Mar 2010 Posts: 194 Downloads: 64 Uploads: 0	There was a purely hydrophone targeting method posted in the SH4 section on SubSim several years ago. I don't have it book marked or anything. A search might turn up something. Basically, it involved taking 4 bearings and precise time intervals and drawing a straight line through those bearings that would be equally spaced. That is IF the ship didn't change course and didn't change speed. I've pulled off many a torpedo shots in heavy fog and rain. But I used the radar to get the target's heading and speed. I use a method of distance traveled / elapsed seconds * 1.8 = knots. Then I would line up on a 90 degree perpendicular to the targets heading and set up my TDC computer for the distance, AoB, and speed settings to cross at either 225 or 45 depending if it's coming in from my port or starboard side. I would engage the TDC computer at the time the sonar reading crossed my preset bearing. In fact I tend to use this method even on clear days because I don't want to take a chance on the enemy spotting my periscope. Then I'd simply open doors and fire after. Of course I already had the depth and speed of the torpedoes already set by then. If you're only about 1000 yards away from the targets path, you just about can't miss. The US side is very tough to set up for multiple targets, unlike the German U-Boat side. Sorry I couldn't be more help for the full sonar method though.