Abstract: A VTOL-type air vehicle is transitioned from forward speed mode to hover mode via a transient path in transition mode. The air vehicle includes first and second propulsion systems, and high lift, mild stall fixed wings. The first propulsion system can provide a first thrust (sufficient for enabling powered aerodynamic flight) at a first thrust vector. The second propulsion system can provide a second thrust (sufficient for enabling vectored thrust flight) at a second thrust vector, which is spatially fixed with respect to the air vehicle at least during transitioning. The transient path includes, during transitioning, manipulating a first magnitude of angle of attack and a second magnitude of forward speed to provide a corresponding aerodynamic lift component, and concurrently manipulating a third magnitude of the second thrust to provide a vertical vectored thrust component corresponding to the first magnitude of angle of attack.

Abstract: A propulsion system, including a rotor arrangement rotatably mounted with respect to a nacelle about a rotor axis. The rotor arrangement includes rotor blades, each being pivotably mounted to a hub element about a respective blade pivot axis, the rotor blades being deployable between an undeployed configuration and a deployed configuration. The nacelle includes a nacelle body having a nacelle outer surface including facet elements and transition elements, each facet element extending aft from the hub element, each adjacent pair of facet elements being circumferentially spaced from one another by a corresponding transition element, each facet element having a first curvature with respect to the rotor axis, each transition element having a second curvature with respect to the rotor axis. The first curvature is different from the second curvature. In the undeployed configuration, each rotor blade is in overlying and fully external relationship with respect to a corresponding facet element.

Abstract: A propulsion system, including a rotor arrangement rotatably mounted with respect to a nacelle about a rotor axis. The rotor arrangement includes rotor blades, each being pivotably mounted to a hub element about a respective blade pivot axis, the rotor blades being deployable between an undeployed configuration and a deployed configuration. The nacelle includes a nacelle body having a nacelle outer surface including facet elements and transition elements, each facet element extending aft from the hub element, each adjacent pair of facet elements being circumferentially spaced from one another by a corresponding transition element, each facet element having a first curvature with respect to the rotor axis, each transition element having a second curvature with respect to the rotor axis. The first curvature is different from the second curvature. In the undeployed configuration, each rotor blade is in overlying and fully external relationship with respect to a corresponding facet element.

Abstract: A wing system is provided for an air vehicle, the air vehicle having a fuselage including a fuselage section and a fuselage longitudinal axis, the wing system having at least one wing deployment module. Each wing deployment module includes a set of wing elements, including at least a first wing element having a first wing element longitudinal axis, and a second wing element having a second wing element longitudinal axis. Each wing deployment module is configured for selectively transitioning between a respective stowed configuration and a respective deployed configuration. In the stowed configuration, the first wing element and the second wing element are in overlying relationship such that the first wing element longitudinal axis and the second wing element longitudinal axis are nominally parallel with one another.