Attack an escorted convoy

[skirich]

I tried twice in the china sea to attack an escorted convoy running at 9nm. About 9 ships total.


I was able to put one torpedo on target and then had to dance with the destroyers.


Whoever said the thermal layer is your friend was not joking.


Anyway, I'm looking for some tips on hiting a convoy.
Straight on, 90 degrees, whatever you think works best.


Thanks.

[jimmbbo]

Probably more than you want to know, but I have had success by moving ahead of the convoy 20ish miles, staying at least 5 miles away, setting up just less than 90 degrees to the convoy course line

• Taking on 0 to 3 DDs is relatively easy, but some convoys have at least 4 DDs, which can be risky.
• In firing position the bow is pointed toward the convoy by about 3ish degrees to give better view of the convoy rows.
• I use either autotargeting or the O'Kane method depending on how much work I want to do. Watch for the O'Kane technique, along with his other SH videos

• Draw the convoy course line
• Draw two circles on the course line, one 1500 yd radius and the other 5 miles radius, centered on the intersection of the 1500 yd circle and the convoy course line.
• I set up on the edge of the 1500 yd circle and wait till the first escort is about 5 miles away to confirm/update the target course line.
  • 5 mi is roughly the detection range of most IJN DDs, except some (Akizukis?) show better sonar/hydrophones and detect subs further away, especially later in the war. I submerge immediately if I detect one of them.
  • 1500 yds is far enough away to get a good view of the convoy and choose targets within the max range of the Mk 14 and keep relatively short runs for the torps
• While submerging to 200 ft activate silent running, set the torpedo speed and depth and watch the lead DD sonar position till it's at about the 11 o'clock position
• Bring crew to battle stations, rise to 150 ft to check for DD pings. If a DD is pinging, it's likely they have heard something they suspect.
• When the lead DD is ~dead ahead, up to periscope depth
• Passing thru 100 ft, open outer doors
• At PD, confirm DD location and direction, identify and acquire targets.
  • If the Submariner's Goddess smiles upon you the first row of the convoy will be about 30-45 degrees off the bow.
• Mk14 allocations
  • Large ships - 3 x Mk14
  • Medium ships - 2 x Mk14
  • Small ships - 1 x Mk14
  • Escorted liners - 2 x Mk14
  • Unescorted liners (often in pairs)- 1 or 2 Mk14s each, emergency surface to finish off with deck gun
  • Torpedo speed can be used to get nearly simultaneous torpedo detonations.
    • Distant targets - fast speed (within 4100 yds)
    • Closer targets - slow speed with a delay after firing distant torps
• If escorts are present, as soon as last torp is fired, waste no time submerging in position to 300 ft (using F11 surface view allows you to view your handiwork)
• Below the thermal layer move at 2 kt at an angle toward the center of the convoy
  • The reasoning (which may or may not be valid) is that if I escape below the convoy in the general direction from which it came, the convoy noise will mask my escape
  • Set a zig zag path in the general direction from which the convoy arrived, which increases the distance from the DDs and allows the sonar operator to track the DDs.
  • Confirm DDs are not a threat
    • After about 5 miles, turn 90 degrees to the last known DD direction and confirm via sonar they are no longer a threat
    • Some DDs stop and listen for extended times and may not give a sonar return. They are unlikely to be close enough, but you're in no position to get in a knife fight with them.
    • I you have no radar, come to periscope depth and check for DDs
    • If you have radar, surface to radar depth and confirm it's safe...

Good hunting, Skipper!

[skirich]

Originally Posted by jimmbbo

Probably more than you want to know ...

Thank you very much. I love this tech stuff.