The tiltrotor design borrows from both helicopters and fixed-wing airplanes, and tries to minimize weaknesses of each. Fixed-wing airplanes are fast and more fuel efficient than helicopters, but they require long runways to take off and land. Helicopters, in turn, can take off and land from just about any space that's larger than the sweep of their rotors, but they're inefficient flyers and much slower than airplanes. Tiltrotors get the best of both worlds. They take off vertically like a helicopter, then tilt their rotors forward to fly like an airplane. They can land on runways like a traditional plane, or switch back and land like a helicopter.