Investigations of lightning accidents on automobiles

• Automobile lightning damage information from online sources and field surveys has been gathered; namely, the statistics of lightning attachment points and trends of lightning damage occurrences are compiled.
• Based on the statistics, lightning strokes to vehicles and damages, some lightning protection strategies and importance of research based on both direct and indirect effects have been proposed.
• As unusual cases, the lightning damages of a hybrid car and an industrial vehicle have been introduced.
• The outstanding fire accident of an automobile has been researched.

Many kinds of electronic equipment have been used in recent automobiles. Eco-friendly automobiles such as electric, fuel-cell and hybrid vehicles have spread rapidly. Those automobiles are usually sensitive to electromagnetic disturbance caused by lightning and so on. When an automobile is struck by lightning, lightning current usually flows into the earth through the vehicle body. The corresponding transient electromagnetic fields appearing inside the vehicle and shunt lightning current through electronics systems are considered sources of malfunctions. From an automobile safety and equipment protection viewpoints, investigations of protective measures are imperative. Before lightning protection methodologies are proposed, existing lightning damages to automobiles must be clarified. The statistical data on automobile lightning damage reports by conducting field surveys and web-based researches had been gathered. In this paper, the result of statistical data has been introduced. Right in the middle of the field surveys of lightning protection for automobiles, the outstanding fire accident of an automobile in Kanto district in Japan occurred. Right after hearing the news, interviews against the fire fighters about their field survey had been conducted; the scene of the accident and burned automobile had also been investigated. In this paper, the results of the interview and investigation have also been discussed.