Abstract:
This work presents a self-consistent and self-contained
model to study and analyze aircraft-lightning electrodynamics. In
this paper, we review the well developed and reported transmission
line model of the cloud-to-ground (CG) lightning return stroke.
Subsequently, the incorporation of a circuit model of the aircraft into
the return stroke model is considered. The direct hit characteristics
of aircraft body lightning currents for both CG and GC (ground-
to-cloud) are important when designing protection, shielding and
filtering systems for airborne electronic and electrical systems within
the aircraft system. Moreover, the model will allow design of aircraft
structure and geometry to minimize energy dissipation into the aircraft
structure and systems. Basic electromagnetic theory is used to show
the validity of considering the return stroke as a transverse magnetic
wave along a transmission line. A distributed transmission line model
for the aircraft and the return stroke channel of the lightning is used
to simulate the return strokes of CG and GC flashes. The effects of the
aircraft geometry with sharp edges are included in the computation of
aircraft capacitance values, both distributed as well as lumped values.
The paper compares electric currents, channel voltages, the rate of
change of current and the frequency spectrum along the lightning
channel of the return strokes for CG and GC flashes with aircraft
attached to the channel.
