Pump systems such as, for example, fuel carts are used to move fluid. Fuel carts are sometimes used to fuel and defuel aircraft. Fuel carts may need to perform within given operating conditions. For example, it may be desirable to transfer fuel to or remove fuel from the aircraft at about a constant rate. Similarly, it may be desirable to transfer a set amount of fuel to or remove a fixed amount of fuel from the aircraft in a predetermined amount of time.
Some fuel carts use a first pump when fueling the aircraft and a second pump when defueling the aircraft. Each pump is selected to have properties suited for fueling or defueling, respectively. Having more than one pump adds cost and weight to the fuel cart. Other fuel carts use a single pump to fuel and defuel aircraft. The single pump may be suited for either fueling or defueling, but may not be suited for the other. As an example, a single pump may meet the operating conditions for fueling aircraft, but it may exceed the operating conditions for defueling aircraft. To block the pump from exceeding the operating conditions, the fuel cart may include a power regulator, a gearbox, valves, or valve systems to control the output of the fuel cart.
Accordingly, there remains a need for further contributions in this area of technology, including contributions that increase reliability and control and reduce labor, complexity, cost, and weight of applications.