Propulsion   All forms of propulsion act with Newton's 3rd law to work. Boat props spin to manipulate water and push it away from the craft. Jet engines works in the same way, but in a different way. Wings and hydrofoils create lift by pushing air/water respectively down to create lift, but an additional force from a jet/prop is needed. Wheels use friction to propel a craft forwards with it's rotation. *Above form left to right, top to bottom; Boat Prop, Jet Engine, rudder, Steam Powered Prop, Wheel, and Hydrofoils. An important factor to consider is a craft's center of mass. Propulsion parts need to align with the center of mass so that craft's direction stays forward. This rule is less important in large ships as there mass is too large for propellers to significantly influence. But planes must follow this rule as if their jets are misaligned, then the plane will reenact roller coaster loop-DE-loops and/or nosedives into the water. It can be concluded that kinetic energy and vectors factor into how propulsion works, and that kinetic energy plays a part too. It should be noted that the in-game physics can be altered. Drag included, so that means drag can be negated. And with a boat prop, our phys boat moves at 30 m/s. So that means our boat has a kinetic energy of  142,143,615 kg*m/s.