Definition
An alloy of iron and carbon, often combined with other elements such as chromium, nickel, molybdenum, or vanadium, to produce a metal with high strength, hardness, and durability. Carbon content typically ranges from about 0.1% to 1.5%, and the specific properties of a given steel depend on its alloying elements and heat treatment.
Plain English
A strong metal made mostly of iron with a small amount of carbon mixed in. Other metals can be added to make it harder, tougher, or more resistant to rust.
Context Anchor
Seen in aircraft materials, maintenance manuals, hardware descriptions, control cables, landing gear parts, and engine component discussions.
Derivation
From Old English 'stēli', meaning hard or firm. The word has always referred to a hardened form of iron, which fits its role in aviation as the metal chosen where strength matters most.
Why Pilots Care
Steel is used where strength and fatigue resistance matter most -- landing gear, engine mounts, bolts, and control cables. Knowing which parts are steel (versus aluminum) helps a pilot understand inspection points, corrosion concerns, and why certain components are heavier but trusted to carry critical loads.
Intuition Check
Steel does not just mean any strong metal. In aircraft use, steel means an iron-based metal alloy, not aluminum, titanium, or another aircraft metal.
Example Sentence 1
The landing gear legs are made of high-strength steel to absorb the impact of touchdown.
Example Sentence 2
Landing gear legs are typically made from heat-treated steel to handle repeated heavy loads.