Coming straight from IL2, I have a tendency to control my submarine like a bomber aircraft. In terms of running silent it is very effective. However, since I'm new to the game, I tried last night to do the "Naval Academy's" Convoy Attack mission.
Here's how it went. I started out near the convoy, and so I submerged the sub and brought up the periscope. I situated myself effectively behind the last part of the patrol, a C2 cargo ship, and fired my first torpedo. I sank the boat in 1 hit, and after congratulating a happy crew, We moved toward the next target. By this point the Destroyers had obviously noticed us and our periscope was quite visible, so I had us dive down to 30 meters, still moving forward. The destroyer started searching around for me, and took a wrong turn so I decided to continue with my attack. I blew the ballast, resurfaced rather quickly, manned the deck gun and hid myself between 2 other cargo ships, firing at each one alternately with the deck gun. When the Destroyer was back on course, and able to fire at me without endangering his convoy, I resubmerged. Moving in behind the cargo ships I destroyed them with 2 more torpedoes. I blew the ballast again at this point, as the destroyer was right behind me, and then firing 2 aft torpedoes (firing one, then loading and firing a second one) the second of the 2 connected and disabled the destroyer. Submerging again to keep myself hidden from the target, I moved toward the last cargo ship at a heavy depth of 45 meters. (I love many meters) I planned to do the normal surprise attack by coming up right next to the ship and blowing the ballast tanks, catching them off guard and then using the deck gun to rip them apart.
What ended up happening was a lot more comedic. I blew the ballast tanks and started coming up, I brought the throttle to Emergency power and I could tell I was movin fast. Then I heard a loud clank, and my boat sunk.
I had hit the bottom hull of the ship I was trying to sink!
Talk about stupidity!