Engine-out handling
MU–2s fly quite well on one engine. However, the MU–2’s morphing wing requires some special attention to maintain control in a low-speed, engine-out condition. Pilots learning to fly typical multiengine piston airplanes are trained to assure that the gear and flaps are up to maximize performance. But with the MU–2, retracting flaps at low airspeed with an engine out can result in a complete loss of climb performance. Remember that 26-knot difference in stall speed between flaps up and down? Like a jet, the MU–2 has VYSE speeds for flaps set at the typical 20- and five-degree takeoff settings. MU–2 pilots are trained to leave the flaps alone after an engine failure until accelerating to at least the appropriate VYSE for the next flap setting.
More important than cleaning up after an engine failure is the need for the pilot to get the airplane under control and nail the correct rudder input. After that, the pilot need only adjust the aileron trim (the servo tabs on the flaps that work like ailerons) to trim away the spoiler input. A spoiler raised on the wing of the operating engine doesn’t help your climb rate. Testing verified that it reduces single-engine climb by about 50 fpm. Once cleaned up, a fully loaded MU–2 can expect to climb 500 fpm on one engine.
http://www.mu-2aircraft.com/upload/news/MU2News_115.pdf
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