This work deals with the characterization of DC electric arcs in aeronautical conditions of pressure (104 Pa–105 Pa). Characteristics of electric arcs such as the mean electric field in the arc column, the anode and cathode voltage drops, the length for which the arc extinguishes naturally and the mean energy dissipated per arc have been measured for three current values: 7, 70 and 300 A. The decrease of pressure leads to an increase in the arc length which can be two times longer in pressure conditions reached during a flight than in atmospheric pressure conditions. This is correlated with the variation of the mean electric field with pressure. Consequently, the energy dissipated per arc is also amplified.