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Steeltrap · 12-27-07, 06:42 AM

The following describes my method for a submerged, daylight attack. At night I remain on the surface and approach from a different angle, but the principles of keeping slow and presenting narrow angles applies equally to both scenarios.

I try to approach from maybe 20 degrees off the base track of the convoy.

Make sure you dive early - a DD within about 10km will spot you in daylight, seemingly irrespective of the weather (not too happy about that aspect of the sensors).

Angle towards the point you have selected from which to fire. If you do silent running at 1.5kts DDs won't hear you (this means selecting the speed directly on the alternate engine telegraph display).

Try to keep DDs inside about a 30 deg angle on your bow - you are presenting a smaller target for a return echo from their ASDIC. As they get closer, start turning toward their direction of travel. The idea is to present an angle of less than 30 degrees until they cross your bow. After that you will be astern of them and you can turn back to the course you need for your shot.

I did this recently with the lead escort on a LARGE convoy. It closed within about 1300m at its closest, yet didn't detect me and sailed past. This left me at the front of the convoy with the lead escort behind me and heading away. In such a situation you can line up targets in the nearest column, waiting for them to come to point blank range (I think I was only 650m from track when I fired at the nearest target - the last I fired at, having fired at others further away first - and you don't miss at that range!).

You can then turn so that you are travelling along a reciprocal course as you dive, meaning the rest of the convoy heads over you, giving you excellent cover, both in terms of sound AND sheer physical presence (it's hard for a DD to DC you if you are under a freighter!).

One other thing - raise your periscope to the minimum height required to give you a view, and expose it for as brief a time as possible. In gathering firing data that should mean 5 seconds or less. For firing it can mean only a few seconds if everything is set before you shoot - as it should be.

Works for me.....

12-27-07, 06:42 AM	#3
Steeltrap Grey Wolf Join Date: Mar 2001 Location: Sydney, Australia Posts: 818 Downloads: 3 Uploads: 0	The following describes my method for a submerged, daylight attack. At night I remain on the surface and approach from a different angle, but the principles of keeping slow and presenting narrow angles applies equally to both scenarios. I try to approach from maybe 20 degrees off the base track of the convoy. Make sure you dive early - a DD within about 10km will spot you in daylight, seemingly irrespective of the weather (not too happy about that aspect of the sensors). Angle towards the point you have selected from which to fire. If you do silent running at 1.5kts DDs won't hear you (this means selecting the speed directly on the alternate engine telegraph display). Try to keep DDs inside about a 30 deg angle on your bow - you are presenting a smaller target for a return echo from their ASDIC. As they get closer, start turning toward their direction of travel. The idea is to present an angle of less than 30 degrees until they cross your bow. After that you will be astern of them and you can turn back to the course you need for your shot. I did this recently with the lead escort on a LARGE convoy. It closed within about 1300m at its closest, yet didn't detect me and sailed past. This left me at the front of the convoy with the lead escort behind me and heading away. In such a situation you can line up targets in the nearest column, waiting for them to come to point blank range (I think I was only 650m from track when I fired at the nearest target - the last I fired at, having fired at others further away first - and you don't miss at that range!). You can then turn so that you are travelling along a reciprocal course as you dive, meaning the rest of the convoy heads over you, giving you excellent cover, both in terms of sound AND sheer physical presence (it's hard for a DD to DC you if you are under a freighter!). One other thing - raise your periscope to the minimum height required to give you a view, and expose it for as brief a time as possible. In gathering firing data that should mean 5 seconds or less. For firing it can mean only a few seconds if everything is set before you shoot - as it should be. Works for me.....