What aircraft are built of
Most aircraft on the register are aluminium sheet over a riveted frame. The older light aircraft are welded steel tube under fabric, sometimes with wooden wings; the newest are moulded carbon or glass fibre, and so are nearly all drones. This page sorts the 1984 biggest model families (274,869 aircraft, about 86% of the register) by their main construction. The material decides how an airframe ages and what its inspections look for: cracks and corrosion in metal, rot and fabric life in wood and fabric, hidden damage in composites.
How this list was made
The FAA's register does not record what an aircraft is made of. This list is written by hand from the makers' own descriptions and the FAA's type certificate data sheets, one line per model family, and covers only families whose construction is well documented; the rest show nothing rather than a guess. Where a family changed construction over its life (fabric wings on the early ones, all-metal later), the note on its model page says so. The type certificate data sheet remains the authority for any one model, and the list is corrected when a reader shows it wrong.
Related: an aircraft, system by system · model families · the graph.