1981

V-22 Osprey

The V-22 Osprey is one of those projects where you wonder if engineers bit off a little more than they could chew.

It sounded simple enough when the United States Department of Defense commissioned it from Bell Helicopters and Boeing in 1981: Create an aircraft that can act like a helicopter for takeoffs and landings, and then convert into a normal turboprop airplane. Being able to land like a helicopter means you don’t need a runway. Turboprops use less fuel than helicopters in straight and level flight, and have a higher top speed than helicopters. It’s the best of both worlds.

Then engineers went to design the plane. One problem: engine failure. In a normal twin-engine airplane, the failure of one engine is not a big problem. But on the V-22 in helicopter mode, one engine failure would be catastrophic. So the V-22 needs a driveshaft running through the wing to connect the two engines. But not just a straight shaft. It has to curve over the fuselage and deal with flexing wings, so it has fourteen segments.

The Marines added another requirement—the wings need to rotate to a position parallel to the fuselage, and propeller blades need to fold so the plane takes up less space in storage. That creates lots of complexity. Then mechanical engineers had to add the powerful hydraulic mechanisms to rotate the engines and props during flight. Because this rotation process is so important, the hydraulic system is triple redundant and runs at very high pressure.

Keep in mind that wing tips are normally light. In this plane they are massively heavy. So the wings need to be extra beefy. When you add up the weight of the drive shaft and transmissions, the folding wings and props, the beefy wings and the rotating engines, this plane is carrying a lot of extra baggage. To shed weight, light carbon composites are used in almost half of the aircraft. All of that extra complexity plus the carbon makes the V-22 expensive. Several crashes and design reviews meant the airplane took more than two decades to reach operational status.

Is it worth it? There are a lot of critics. The plane is super-expensive. But engineers did accomplish the goal.

SEE ALSO Carbon Fiber (1879), Helicopter (1944).

A sailor with USS Kearsarge salutes MV-22 Osprey pilots as they take off.