The ignition of aircraft engines is dependent on the creation of a spark at exactly the right moment so that the fuel/air mixture in the engine can be efficiently converted into power.

Spark plugs create the high-voltage spark necessary whilst withstanding extremes of heat and pressure. With its high conductivity, high melting point, high temperature stability and corrosion resistance, ruthenium is ideal for firing tips (the active components in the plugs).

With similar properties, platinum, palladium, rhodium and iridium are used in automobile spark plugs.