Lancet is a torpedo bomber. It has no weapon to fight against land units. However it is able to deal massive damage to any ship/submarine/amphibious unit. Torpedoes need a long open path to drop and accelerate in water. Therefore don’t try to drop them flying from the side of the shore line as they will just get stuck in sand. Remember that in order to locate underwater units you need to use a sonar, preferably a radar/sonar plane.