Losing contact early usually means you are not closing fast enough and/or going the wrong direction.
If you get an initial contact early and lose it, it's possible to swim in the wrong direction and never regain because you are not closing. Even 90 degree variations in the wrong direction for too long can put you off the track.
Be sure to pay close attention to the briefing and stay within 45 deg of that until proven faulty.
The default Narwhal while no one's favorite, will let you overtake quiet boats which have to make a lot of noise to extend distance on you. Also, the added quietness lets you detect quiet boats further away. If you are in the campaign, I could see why you would want to stay with a boat with more versatility than the Narwhal.
Consider you might be too conservative early in the mission after looking at the initial contacts and staying quiet too long. Make note of initial range estimates as soon as you can.
-Pv-
|