A third-generation tiltrotor: two proprotors on tilting shafts, a wing that takes over as you push the nacelles forward, and a conversion corridor where both lift sources share the load. Watch the dual flowfield tilt from downwash columns to propwash streams as you transition from hover to 280 knots.
Key difference from V-22
The MV-75 has fixed nacelles. Only the proprotor shafts and gearboxes tilt. The engines remain stationary in the wingtip nacelles at all times. This eliminates the nacelle-induced pitching moment during conversion.
Proprotor wake dynamics
A tiltrotor proprotor operates across two fundamentally different aerodynamic regimes. In helicopter mode the wake contracts below the disc exactly like a conventional rotor (contraction ratio ~0.7 at hover). As the nacelles tilt forward, the wake transitions into a propeller-mode slipstream: the inflow reverses direction relative to the disc, the tip vortices form a tight trailing helix rather than a descending tube, and the blade loading shifts from the outboard region inward.
At intermediate nacelle angles (30–75°) both regimes coexist on the same disc. The advancing blade operates in near-axial flow while the retreating blade still sees a strong edgewise component. This asymmetry drives 1/rev flapping loads that peak mid-conversion — the structural design case for the proprotor grip and yoke.
The V-280 class addresses this by using a stiff-in-plane gimballed rotor with matched flap/lag frequency separation, keeping 1/rev loads within the fatigue envelope across the full 0–97.5° tilt range. Counter-rotation of the two proprotors cancels the net 1/rev rolling moment on the airframe.
Controls
Collective controls power, cyclic pad tilts the aircraft, pedals control yaw. The nacelle tilt lever transitions between helicopter and airplane mode. SAS provides stability augmentation. Cockpit units: knots, feet, ft/min.
Drag to orbit the camera, scroll/pinch to zoom. The wake particle field shows the induced flowfield — watch it tilt from vertical downwash columns (hover) to horizontal propwash streams (airplane mode) as you convert.
Disclaimer
This is an independent project, not affiliated with Bell, Textron, or the U.S. DoD. All parameters are from public-domain literature. Concept demonstrator only — not for flight training or operational planning.
The software implementation, architecture, visualizations, and creative expression herein are the intellectual property of Transpire Dynamics LLC. Unauthorized reproduction, redistribution, or derivative use of this work is prohibited.
This is an independent project. It is not affiliated with, endorsed by, or derived from any controlled technical data of Sikorsky, Lockheed Martin, Bell, or the U.S. Department of Defense. All aerodynamic parameters are sourced from publicly available, open-domain literature.
These are concept demonstrators, not engineering tools. Not for flight training or operational planning. For full-fidelity analysis, visit our site.