The two seats in the control area were occupied by the Diving Officer (the inboard or nearest seat) and the Helmsman (outboard seat). The two shared the positioning of the x-stern control surfaces. The Helmsman was responsible for using the rudder function to steer the ordered course. The Diving Officer, using the diving plane function, was responsible for reaching and maintaining depth. The inboard (Diving Officer) set of controls could be electrically connected to control both the diving planes and rudder. Using the buttons on top of the control wheel, the Diving Officer also controlled the dorsal rudder located on the aft end of the sail. The row of red lights directly in front of the Diving Officer indicated the position of the dorsal rudder.