Shape-Shifting Wings, From Soviet War Planes to Top Gun’s Tomcat

As a jet approaches supersonic speeds, air compressing at the front of the wing causes drag. Engineers figured out that sweeping the wing back can disrupt this drag effect. However, at low speeds this sweep causes air to travel along the wing (from root to tip) instead of over it. This makes jets stall, and stalling makes jets crash. Jets with a mechanically adjustable wing angle, like the F-14, solved this problem. CDR David Baranek/US Navy

As a jet approaches supersonic speeds, air compressing at the front of the wing causes drag. Engineers figured out that sweeping the wing back can disrupt this drag effect. However, at low speeds this sweep causes air to travel along the wing (from root to tip) instead of over it. This makes jets stall, and stalling makes jets crash. Jets with a mechanically adjustable wing angle, like the F-14, solved this problem. CDR David Baranek/US Navy

Take off. Rise. Soar. Bank. Turn. Stall. Swoop. Dive. Land.

For each of the different kinds of flying an airplane has to do, there’s an ideal shape and configuration for its wings. Even though bird-like flappability isn’t feasible with struts and steel, engineers since the dawn of aviation have been trying to make wings that change shape.

Sometimes the morphing seems inevitable, like the wing flaps that most planes use to steer. Other cases, like the airfoils that sweep back to a vee and carry our fighter jets to supersonic speeds, could only have come from trial-and-error arms races. And then there are the oddballs, the telescoping, twisting, torquing shapeshifters.

Any engineer can tell you that solving one challenge often means introducing others, sometimes catastrophic. For every morphing wing design that makes it into the aeronautics canon, there are dozens of others that survive only in footnotes, photographs, or the graveyard.

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