[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!