Make sure the crew isn't tired, that's a big thing you have to watch. IF you get an aircraft thats too close to dive in time to get away, man the flack guns, order flank ahead do a hard turn port or starboard to increase your chance of getting away.
You can also boost the watch crew experience by having a watch officer who is quailified. That will give all all the crew a boost. Make sure after you surface that the Watch officer is on station, if he isn't then your new boys may not see there feet!
Now go forth and "Be more aggressive!"