A cross rod for use in a toggle mechanism including a first section, a second section and a midsection between the first section and the second section. The midsection includes a flange having a through hole. The first section has a first diameter, the second section has a second diameter, and the midsection has a third diameter. The third diameter being larger than at least one of the first diameter and the second diameter.

According to one embodiment, a ram air fan inlet shroud for a ram air fan assembly of an aircraft is provided. The ram air fan inlet shroud including: a shroud portion extending outwardly from a conical portion, the conical portion providing a transition between a central portion and an inner ram air fan hub interface portion, the conical portion including a plurality of inner cooling holes, a diameter of each of the plurality of inner cooling holes is about 0.406 inches (1.031 cm); and a recessed portion located between the inner ram air fan hub interface portion and an outer ram air fan hub interface portion, the recessed portion including a plurality of outer cooling holes.

Systems, apparatuses, and methods for overcoming the disadvantages of current air transportation systems that might be used for regional travel by providing a more cost effective and convenient regional air transport system. In some embodiments, the inventive air transport system, operational methods, and associated aircraft include a highly efficient plug-in series hybrid-electric powertrain (specifically optimized for aircraft operating in regional ranges), a forward compatible, range-optimized aircraft design, enabling an earlier impact of electric-based air travel services as the overall transportation system and associated technologies are developed, and platforms for the semi-automated optimization and control of the powertrain, and for the semi-automated optimization of determining the flight path for a regional distance hybrid-electric aircraft flight.

A single-unit nose cone for a ram air including: a dome portion located at a forward end of the single unit nose cone; a dome stand portion adjacent to the dome portion; a seat portion adjacent to the dome stand portion; and a stem portion adjacent to the seat portion and located at an aft end of the single-unit nose cone, wherein the dome portion, the dome stand portion, the seat portion, and the stem portion are composed from a single piece of material having a density of about 0.286 pound/cubic inch (7916 kilogram/cubic meter).

An actuator includes an inverter, a stator, a movable part, a controller, an injector, a current detector, and an estimator. The inverter is driven by a power generated by the axial force of an engine, etc. The stator includes an armature coil driven by the inverter. The movable part applies a driving force to at least one of a rudder surface of a tailplane of the airplane, etc. The controller controls the inverter in accordance with a signal from a maneuvering system. The injector injects a high-frequency signal into the coil. The current detector detects a coil current. The estimator estimates a position of the movable part.

A ram air turbine (RAT) is provided and includes a turbine assembly including blades and a hub to which the blades are connected, a generator or a pump and a drivetrain mechanically interposed between the turbine assembly and the generator or the pump. Each blade includes an exterior, airfoil-shaped structure defining an interior and support structures disposed within the interior which connect with an inner surface of the exterior, airfoil-shaped structure and which define hollow regions within the interior.

A ram air turbine (RAT) can include a housing and a turbine shaft configured to connect to one or more turbine blades and be turned by the one or more blades. The turbine shaft can be disposed in the housing to rotate relative to the housing along a rotational axis. The RAT can include a first bearing and a second bearing mounted between the turbine shaft and the housing to allow the turbine shaft to rotate relative to the housing. The RAT can include a whirl reduction system configured to dampen or eliminate whirl around the rotational axis.

A ram air turbine system includes a ram air turbine and an actuator to move the ram air turbine between a stowed position and a deployed position. The actuator is in fluid communication with an aircraft hydraulic system configured to return the ram air turbine to the stowed position from the deployed position during operation of the aircraft utilizing hydraulic fluid pressure from the aircraft hydraulic system. A method of operating a ram air turbine system includes slowing or stopping rotation of the ram air turbine during flight of the aircraft, directing hydraulic fluid pressure from an aircraft hydraulic system to a ram air turbine actuator to urge movement of the actuator from a deployed position to a stowed position and urging movement of the ram air turbine from a deployed position to a stowed position via movement of the actuator from the deployed position to the stowed position.

A ram air fan and fan bypass shutoff check valve assembly includes a ram air fan configured to draw an airflow through a fan inlet, and a ram fan bypass duct positioned downstream of the ram air fan. The ram fan bypass duct includes a valve assembly configured to selectably direct the airflow through the ram air fan when the valve assembly is in an open position, and direct the airflow through a bypass duct thereby bypassing the ram air fan when the valve assembly is in a closed position.

A ram air turbine (RAT) actuator piston can include a body defining a piston structure having an inner cavity. The piston can include one or more damping holes axially defined through the body to the inner cavity and a lock rod hole defined axially through the body to the inner cavity. The lock rod hole can have a larger flow area than one or more of the one or more damping holes. The lock rod hole can be configured to receive a lock rod of a RAT actuator to at least partially block flow through the lock rod hole when the lock rod is in a locked position. The one or more damping holes can be configured to allow flow through the damping holes in the locked position to allow the RAT actuator piston to move within the RAT actuator in the locked position to dissipate vibratory loads.