Lightning Direct Effects
Section 10: Environmental Qualification (DO-160)
Definition
The physical damage caused by lightning attachment to the aircraft structure, including burning, blasting, bending, and pitting at the attachment and exit points, as well as resistive heating and magnetic force effects along the current flow path. Direct effects are addressed through structural design, material selection, and the provision of adequate current-carrying paths that prevent catastrophic structural failure or fuel ignition.
Where This Shows Up
Lightning direct effects are primarily a structural and fuel system concern rather than an avionics equipment concern. However, avionics equipment installed in lightning attachment zones (particularly external antennas, pitot probes, and equipment mounted on external surfaces) must be designed to withstand or be protected from direct lightning effects. The lightning environment is defined by SAE ARP5412, which specifies the current waveform components (Component A through D and Component H) representing different phases of the lightning flash. Zoning of the aircraft identifies the probability and severity of lightning attachment at each location.
Primary Sources
Aircraft Lightning Environment and Related Test Waveforms — defines the external lightning environment including current components and zoning.
Aircraft Lightning Zoning — defines the lightning strike zones on the aircraft and the associated direct effects environment.
Protection of Aircraft Fuel Systems Against Lightning — FAA guidance on protecting fuel systems from lightning ignition sources.
Related Terms
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