You may have noticed that all three times you were attacked you were on the surface. Stop that! You are a submarine. When you have 20m of water below your keel, dive!
Yes it takes a long time to reach your patrol area if you travel submerged. It takes longer if you are dead.
From late '42 onward, airplanes will kill you. This is especially true if you are driving a IX boat. Those pigs just cannot get out of the way fast enough.
My advice from late '42 onwards is:
- If you are in an area where enemy aircraft operate, stay submerged, except:
- to recharge batteries, or
- when fog is medium or heavy (aircraft can't fly)
- Upgrade your batteries
- Travel submerged at 1.8 knots to conserve battery power
- When surfaced and winds are below 10m/s, run with decks awash to reduce dive time (decks awash not available in stock)
- When surfaced, run at at least 10 knots to improve dive time
- Recharge batteries in daylight, so you can see those aircraft coming