Those of us who have had the opportunity to go to an airshow and watch the amazing flight characteristics of the F22 can testify to the amazing movements this aircraft can make as it wings its way across the sky. Some of these maneuvers simply defy logic to our eyes, and create even greater challenges to opposing pilots in air-to-air combat exercises.
Next on the horizon is technology which will allow aircraft to change the actual shape of the airfoil called a wing. No, not just flaps and ailerons, but the overall shape of the wing itself. The process is called morphing, and is patterned after the flight characteristics of the common swift bird. Scientists and engineers have studied birds to see how they change the shape of their wings while in flight.
For example, all of us have seen video where an eagle soars high in the sky with it's wings fully extended as it scours the earth below for it's prey. Once located the wings fold neatly against the side of the bird as it dives on it's prey and then swoops back into the sky, prey in talon.
Well, if we could control the shape of the wing of an aircraft to match optimal performance for each stage of flight - takeoff, climb, cruise, descent and landing - then we could reduce noise by the aircraft combined with more efficient cruise performance.
Mechanical engineering professor Shaker Meguid is currently developing aircraft wing designs that imitate the amazing flight of birds by altering the planform of the wings in order to optimize the aerodynamics for a given flight stage. To achieve these seamless transitions in wing shape, Meguid and his research team are combining two types of advanced materials. The first is shape memory alloy (SMA), which contracts when heated above a certain temperature. The second are piezoelectrics, which compress or extend when an electric field is applied to them. They plan on using these materials to allow the wing to change shape and respond to an aircraft's changing mission with an overall reduced system complexity.
Once again, it seems, aviation is leading the way in technological advances. I can hardly wait to see this technology used on an aircraft in flight. What will they think of next?
Until next time keep your wings straight and level Hersch!
The butterfly, the cabbage white,
(His honest idiocy of flight)
Will never now, it is too late,
Master the art of flying straight,
Yet has — who knows so well as I? —
A just sense of how not to fly:
He lurches here and here by guess
And God and hope and hopelessness.
Even the aerobatic swift
Has not his flying-crooked gift.
— Robert Graves, 1938