Aviation industry is moving towards to more electrical aircraft concept because the demand for power is increasing day by day. As the power density and voltage level rises, challenges in power distribution and protection systems increase. Among the challenges, electrical arc faults are the most dangerous events for an aircraft. In order to prevent any failure caused by arcing, understanding the characteristic of an arc should be the first action. This study presents arc failure types and a new dc series arc model to understand the arcing behavior in electrical power system of new generation aircraft.