Dynamic Start is a term used to describe the process of starting a vehicle with an internal combustion engine. It involves the use of two different types of energy sources, HYDRO and aero. HYDRO is a five letter word that refers to the use of water or other liquid fuel sources to power the engine. Aero is a four letter word that refers to the use of air or other gaseous fuel sources to power the engine. Together, these two energy sources create the dynamic start process.