Tactics against the convoy

[kylania]

Originally Posted by dinazor

I attack 5-7 kms away from convoy. Therefore I always use T1 torpedo. Salvo 4-5 torpedos to convoy, generally hit one or two ships then deep to 150 m and run away, reload of torpedos and attack again.

I only found british carrier with 6 DDs in may 1944 far away of Ireland. I had only one torpedo, attack from 9 kms but missed.

Hmm. I should try that. I usually close within 1200m or so, or sometimes inside the convoy ranks even. Maybe I'll do better from farther away?

[TorpedoMo]

My most used tactic in attacking convoy was to set myself in front of the convoy with the convoys course, silent running, then let myself drop into the convoy by two ways: 1. Manouver out the escort(s) in front if possible on periscope depht or 2. dive deep and come up as soon as the escort run over.
Then, in the convoy I try to get between two lines, looking out for the fat ones, and then take them out by in german called "rechtwinkelschuss", 90° shot. Thats a good way, just let the ships pass by slowly to your left and right, a make your torps go.
This tactic works in the earlier years of war. By progress of war, the better and more escorts make the manouvering near and inside the convoy very dangerous.

[kylania]

I just had an awesome convoy attack, nearly perfect.

Got a report of a convoy coming my way. I moved to intercept and was in place, 5km off their port side as they approached. I inched my way forward as they closed so I'd be approx 1km from the close line of ships I'd estimated.

I did make one mistake and as they closed I peeked with my periscope and forgot to lower it and they actually sent bombers after me! I got hit once and moved. The convoy didn't change course.

The lead escort went past my bow, the edge escort extremely close to my stern, but both passed me as I moved undetected.

I took 4 shots but got greedy! The front row of ships was medium cargos, but a far row had some large troop and tankers! I fired at those. 2 Type IIIs and 2 FATs. One Type 2 exploded early. The other hit a troop ship. The FATs just went off on their merry way and were never heard of again.

After launching I sped up to 2kts, dropped to 40m and inched INTO the convoy. After I heard the first row of ships pass amazingly close over head I turned starboard and headed out of the rear of the convoy. There was some depth charging and pinging, but nothing near me.

As I exited the convoy I popped up to periscope depth and shot a homing torpedo at a passing ammunition ship. Hit!

The escorts never knew where I was. Only sunk two ships (5.7K troop and 7K ammo) but misses aside, I feel it was a picture perfect attack.

[predavolk]

This could be pages of material. Briefly:

Early War - sneak in the gaps between the escorts at PD, running silent, in medium-heavy seas

Mid War - as above, heavy seas important

Late War - shoot from outside the convoy

XXI - load up on homing torps, ravage the escorts, sink the convoy unmolested

[Bosje]

surface attack at night, decks awash and slow speeds, creeping up on them between lead and flank escorts. firing 2 or 3 shots from around 3 km at 60 degree AoB, periscope depth while reloading 2 tubes and run straight into the convoy lanes as the first shots hit. you'll get another 4 or 5 shots (sterntube) off at decent angles from inside the convoy lanes before diving to safety.

not easy but potentially very rewarding, will work well up to 1941 at least. i had one successful surface attack as late as 1943 in rough seas, their radar is not 100% sure to get you

[Graf Paper]

So far, my usual method for attacking a convoy is to use the ruler to draw a baseline of their projected course and the protractor tool to mark a 90 deg. line to plot my interception point.

I set myself up a few km ahead, go to 40m depth and sit quiet while I mark my targets as they approach, trying to ID ships by their sound. I then nudge into the lanes and drift as the escorts pass by overhead.

Once the first few rows of merchies go past, I rise to periscope depth and start launching my torps, using my stern tube for the smaller ships that usually occupy the outer column behind me. I turn as needed to line up my targets, aiming for the boilers, one eel per target.

The idea there is to cripple as many ships as possible, forcing the bulk of the convoy to leave them behind. I go as deep as I can and try to evade and wait out the escorts until they have to leave to protect the convoy. Once the coast is more or less clear, I rise back to 14m and finish off the damaged ships with my reloads or deck gun, if seas permit.

Of course, that's not the only way I go after convoys but it's the method I use most often.

With my 13th patrol set to begin sometime in March 1941, I'm sure that a lot of tricks and tactics I've learned will need to be changed or replaced very soon.

[unterseemann]

I try to get ahead of the convoy on their supposed course, it's quite difficult sometimes as they often zig-zag (realism 100%, no map contact update).
Periscop depth, silent running and hydrophon check when i think it's good.
When i see the leading escort i try to guess the distance between my sub and the escort, usually around 8500m. So convoy is around 10.000m away but i can't usually see them at this moment. 10.000 m means that a 7kts convoy need around 45 min to do this distance. I start immediately to go to -155m depth at 3kts ( i think escorts can hear you if you make 4kts). It took 12 min to reach this depth with a type VIIB. As i need 22min to get back to periscop depth at 2 kts, i will spend 5 min at -155m at 2kts. During this manoeuver i try to keep leading escort in my 0 with the help of hydrophons and when i reach -45m i try to get perpendicular to the convoy route.
So when i get back to PD the convoy is near, and most of the time i'm in a very good position to attack. The last seconds before seeing the convoy are very exciting! Then i fire two salvos of two torpedoes for ships up to 5000tons or single shot for light targets.

This works in jun 41 with absolut calms seas (0 m/s), hope it helps!