Request urgent lessons in submerged evasion techniques

[Eichenlaub]

Fellow Kaleuns!

Please help out this unfortunate commander. I truly am at a loss. I thought I did all the right things but alas, I am getting killed all the time now so it's time to face the music: I seem to be incapable of evading the escorts after I carry out a torpedo attack on a convoy.

I had hoped to start a new career with NYGM/GW at 100% realism and DID when I buy a new pc in a few months' time, but in light of my current performance in convoy battles, I doubt I would live past 1940-41.

I'm currently around July 1944 in a Type XXI, running a stock game patched to 1.4b; realism is set at 79%.

From 1943 I found that the DD's and DE's are incredibly apt to detect me. After launching torpedoes, I rarely get a chance to escape unharmed. My latest patrol drove this home in a way I've not yet encountered before. Out of the 6-7 attempts I've made, I got killed in each and every one. I've hit a new low.

This is the situation: I have sunk a DD or DE and have a convoy in my sights. I fire at a TT and two T3's. Though I usually sink two of them, that's when the trouble begins. The escorts come charging at me immediately. Due to the convoy set up, I usually spot the warships when they are around 800 meters away. Sometimes I can destroy a single warship but this convoy is protected by enough ships to continue the hunt for my poor Type XXI.
I dive quickly. But whatever I do, I cannot prevent being pinged by the enemy. Worse, being pinged by these escorts equals being killed. It might take a few minutes, or even half an hour, but they always seem to know perfectly at what depth I am. The measures I take are these: slow to 1 knot, run deep (around 200-225m) and always have some degrees on the rudder (10-15, to any side desirable at the time). Sometimes I remained undetected for 10 minutes...but then they ping me nonetheless. Since they always seem to know the depth I'm at (I thought ASDIC/Sonar only gave heading and range?), I get hedgehogged and depth charged invariably. I can usually escape the hogs, but the depth charges are another matter. Often the first hit damages or even destroys something critical, like all of my electric engines, my dive planes, rudder or simply reduces my HI by so much as to make my 200 meters of depth unsound.

I always thought that running silent at 1 knot at 200m would do it, but these warships detect you eventually. Evading depth charges at flank speed will only result in a "We've been detected message" withing 30 seconds of ordering flank speed only increasing their knowledge about my whereabouts.

My questions are:
-are these occurrances normal?
-what other counter measures should I take?
-any other good tips for late war convoy battles or evading while submerged?

Currently drowning my sorrows in Bavaria...no no, not the region, the BEER!

Kind regards,

Eichenlaub