This paper presents a state-space technique for the transient analysis of power systems arcing faults, using the time-dependent dynamic resistance model. The state equations describing the system behavior are derived and these equations are solved by the use of numerical integration. Based on the solution technique, a computer program in the MATLAB environment is developed. The computer program is capable of directly formulating the state equations for a transmission line with a fault arc and it produces data for the arc voltage, current and resistance. (C) 2005 Elsevier B.V. All rights reserved.