The problem of penetrating through nets and other objects is solved by cutting the object using a linear cutting assembly having a linear cutter arm that moves in an arc and pivots about an attachment point. The object is cut by a severing action caused by a moveable blade of the linear cutting arm moving back and forth across a stationary blade of the linear cutter arm. An underwater vehicle modified to incorporate an embodiment of the linear cutting assembly can cut a sufficiently large opening in the object to allow the vehicle to pass through.