The dual-role airfoil is accomplished by one of several design approaches:
Typically, flight control software would perform much of the complex transition between the distinct helicopter and aeroplane modes; while automated systems are usually provided to inform crews on the optimal tilt angle and air speed to pursue. Furthermore, it is typical for flight controls, such as blade pitch, to both resemble and function akin to their counterparts on conventional rotorcraft, easing the transition of conventional helicopter pilots to such vehicles.
Proprotors can be designed to fold for storage purposes.Currie, Major Tom P., Jr., USAF. "A Research Report Submitted to the Faculty, In Partial Fulfillment of the Graduation Requirements: The CV-22 'Osprey' and the Impact on Air Force Combat Search and Rescue" (PDF). Air Command and Staff College, April 1999. However, in the case of the V-22, in order to facilitate proprotor folding, the proprotor's diameter had to be constrained to a diameter of 38-foot (11.6 m), five feet (1.5 m) less than optimal for vertical takeoff; this difference has been attributed for causing relatively high disk loading.Whittle, Richard. " Flying The Osprey Is Not Dangerous, Just Different: Veteran Pilots " defense.aol.com, 5 September 2012. Retrieved: 16 September 2012. Archived on 3 October 2013.
In a typical implementation, both proprotors must be rotating in order to maintain flight in helicopter mode. To guard against instances of single engine failure, on both the V-22 and AW609, both engines are connected by to a common central gearbox so that one engine can power both proprotors if such a failure occurs.Norton 2004, pp. 98–99. Despite this provision, the V-22 is generally not capable of hovering on a single engine.Whittle, Richard. " Fatal Crash Prompts Marines To Change Osprey Flight Rules ". Breaking Defense, 16 July 2015. If a proprotor gearbox fails, that proprotor cannot be feathered, and both engines must be stopped prior to an emergency landing. The autorotation characteristics are poor partly due to the rotors' low inertia.McKinney, Mike. "Flying the V-22" Vertical (magazine), 28 March 2012. Archived on 30 April 2014.
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