What two types of organic fibers are used for covering aircraft?

• A. Cotton and linen
• B. Wool and silk
• C. Cotton and polyester
• D. Hemp and jute

Answer: (A)

Natural fabric coverings for early aircraft were made from plant-based fibers because they’re lightweight, relatively strong for their weight, and can be treated with coatings to tighten and seal the surface. Cotton and linen fit that role best: both are cellulose fibers, widely available, and when fabric coverings were doped (coated) they produced a smooth, airtight skin on wings and fuselages. Linen typically offered good strength-to-weight and resistance to stretch, while cotton was easier to weave and commonly used.

Wool and silk, while natural, aren’t the standard coverings used for this purpose. Silk appeared in some niche, high-performance applications, but isn’t the typical fabric for general aircraft coverings. Cotton and polyester mixes introduce a synthetic fiber, which isn’t in the “organic fiber” category in this context. Hemp and jute are natural fibers, but they weren’t used as the primary aircraft fabric coverings. So cotton and linen are the classic organic coverings for aircraft.