Analysis of Available In-Flight Measurements of Lightning Strikes to Aircraft 1999-01-2397

In the European FULMEN program, a collection together with an analysis of available data on lightning have been collected in a public database produced by Aerospatiale. This database contains data on In-flight and ground measurements, on In-flight incidents and manufacturer transfer functions.

In this paper, the data of the in-flight measurements are presented. The In-flight data have been extracted from the Convair and Transall campaigns performed during summer 1985 and 1988 respectively. The measurements have shown that a lightning strike to an aircraft can be decomposed into four main phases: (1) the pre-breakdown phase associated with the general electrostatic condition just before the lightning, (2) the leaders development phase, (3) the recoil streamers phase and (4) the continuous current phase. For each phase, the main physical parameters (current, number of impulse current, impulse period, impulse duration, electric field, …) have been collected. Averages and cross correlation have been determined on these parameters. At the end of the analysis, the typical current waveform inferred from the measurements is shown and discussed.