An understanding of the alloy-environment interaction is essential for maintaining and improving the performance of components in many high temperature applications, In this work, a new approach - Impedance Spectroscopy, IS, measurements in a propane gas flame plasma - was used to study the oxidation process in situ on Kanthal (R) APM, a commercial alumina forming heat resistant powder metallurgical Fe-Cr-Al alloy used in many high-temperature applications. The flame plasma behaves in some respects like a low conductivity electrolyte and the capacitive and resistive response of the alloy - flame plasma system are revealed in the measurements. Pre-oxidation of the samples gave a noticeable contribution, however, the flame constitutes a substantial part of the total impedance of the system and the gas flow showed a significant influence on flame conductivity, The IS method is nevertheless clearly applicable for in-situ high-temperature corrosion studies although further improvement of the flame plasma stability is desirable for continued in-situ characterisation of oxide films at high temperatures.