Definition
A soft, silvery-white metallic element belonging to the platinum group of metals. Palladium is highly resistant to corrosion and oxidation, has a high melting point, and has the unusual ability to absorb large quantities of hydrogen gas. In aviation, it is used in electrical contacts, spark plug electrodes, and as a catalyst in certain chemical and electroplating processes.
Plain English
A rare, silver-coloured metal that resists rust and tarnish very well. Because of this, it is used in small but important aircraft parts where reliable electrical contact and resistance to heat and corrosion matter.
Context Anchor
Seen in aircraft maintenance, electrical component descriptions, material specifications, and parts information.
Derivation
Named after the asteroid Pallas, which was discovered in 1802, the same year palladium was identified as an element. Pallas in turn comes from Pallas Athena, the Greek goddess of wisdom. Knowing this is mainly a memory anchor -- the name has no descriptive meaning about the metal itself.
Why Pilots Care
Palladium-tipped spark plug electrodes and palladium electrical contacts last longer and perform more reliably in the harsh, high-temperature, high-vibration environment of an aircraft engine and electrical system.
Example Sentence 1
The fine-wire electrodes in some aircraft spark plugs use palladium alloys to resist erosion from the heat of combustion.
Example Sentence 2
Palladium-based temperature probes remained stable even after prolonged operation at high power settings.