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Engineering

Assessing the Aeroelastic Stability of a High-Altitude Long-Endurance Aircraft Wing

Quick fact

HALE aircraft wings can have a flutter speed that is only 1.2 times their cruise speed, leaving a very narrow margin for safety, unlike typical commercial aircraft where the margin is often 2.0 or more.

Why this is interesting

Before a storm, a flag whips violently, its fabric rippling in chaotic waves. A HALE aircraft wing is like a giant flag, and if engineers get the design wrong, it can tear itself apart in calm skies.