This paper presents a location algorithm for series arc fault in an AC 230 V - 400Hz aircraft electrical system. At both ends of the line, currents and voltages are recorded for each arc fault generation associated to a specific fault distance. A fault map trace is created by using signature coefficients obtained from Kirchhoff equations which allow a virtual decoupling of the line's mutual capacitance. Then, the calculation of signature coefficients using Kirchhoff equations is done by considering hypothetical fault distances where the fault can appear. This procedure allows to obtain a curve with a linear trend. Finally the unknown fault distance is estimated at the intersection of this curve with the fault map trace. The method is validated through simulations using the MATLAB software.