A cooling duct configured to introduce air flow to a cooling target device provided in a helicopter body of a helicopter includes a duct body, a front opening, an upper opening, a hinge, and a movable blade. The duct body is mountable below a main rotor of the helicopter to be adjacent to the cooling target device. The front opening is formed on a forward side of the helicopter body in the duct body. The upper opening is formed on an upper side of the helicopter body in the duct body. The hinge is disposed in an upper portion of the duct body and includes a pivot shaft extending in a lateral direction of the helicopter body. The movable blade with an end that is pivotally supported by the hinge is provided to be pivotable about the pivot shaft between a first position and a second position.

A method of providing active flow control for an aircraft includes cooling a liquid coolant in a heat exchanger by circulating a cooling airflow through the heat exchanger, and providing fluid communication between the cooling airflow and a boundary layer flow of at least one flight control surface of the aircraft. The cooling airflow affects the boundary layer flow of the flight control surface(s) to provide active flow control. A method of cooling an engine core of an engine assembly includes circulating a cooling fluid through the engine core, and cooling the cooling fluid with a cooling airflow used to provide active flow control to a flight control surface of the aircraft. An active flow control system for an aircraft is also discussed.

A method of providing active flow control for an aircraft includes cooling a liquid coolant in a heat exchanger by circulating a cooling airflow through the heat exchanger, and providing fluid communication between the cooling airflow and a boundary layer flow of at least one flight control surface of the aircraft. The cooling airflow affects the boundary layer flow of the flight control surface(s) to provide active flow control. A method of cooling an engine core of an engine assembly includes circulating a cooling fluid through the engine core, and cooling the cooling fluid with a cooling airflow used to provide active flow control to a flight control surface of the aircraft. An active flow control system for an aircraft is also discussed.

A cooling architecture for an integrated hydrogen-electric engine having a radiator and a hydrogen fuel cell includes a t and a manifold. The turbine is disposed in fluid communication with the hydrogen fuel cell. The turbine is configured to compress a predetermined amount of air and direct a first portion of the predetermined amount of the compressed air to the fuel cell for generating electricity that powers the integrated hydrogen-electric engine. The manifold is disposed in fluid communication with the turbine and positioned to direct a second portion of the predetermined amount of compressed air to the radiator for removing heat from the radiator.

A cooling architecture for an integrated hydrogen-electric engine having a radiator and a hydrogen fuel cell includes a t and a manifold. The turbine is disposed in fluid communication with the hydrogen fuel cell. The turbine is configured to compress a predetermined amount of air and direct a first portion of the predetermined amount of the compressed air to the fuel cell for generating electricity that powers the integrated hydrogen-electric engine. The manifold is disposed in fluid communication with the turbine and positioned to direct a second portion of the predetermined amount of compressed air to the radiator for removing heat from the radiator.

A turbine engine heat exchanger has: a manifold having a first face and a second face opposite the first face; a plurality of first plates along the first face, each first plate having an interior passageway; and a plurality of second plates along the second face, each second plate having an interior passageway. A first flowpath passing through the interior passageways of the first plates, the manifold, and the interior passageways of the second plates.

A turbine engine heat exchanger has: a manifold having a first face and a second face opposite the first face; a plurality of first plates along the first face, each first plate having an interior passageway; and a plurality of second plates along the second face, each second plate having an interior passageway. A first flowpath passing through the interior passageways of the first plates, the manifold, and the interior passageways of the second plates.

A thermal management system includes a refrigeration circuit that cools at least a first coolant that circulates around a battery cooling loop. Refrigerant of the refrigeration circuit is cooled at a liquid-cooled condenser and at an air-cooled condenser. In certain examples, the liquid-cooled condenser is cooled by coolant circulating along a propeller arrangement cooling loop. In certain examples, the coolant from the propeller arrangement cooling loop may be combined with coolant from the battery cooling loop.

An aircraft blade assembly, including: a blade extending from a blade root to an opposite tip; and a heat exchanger disposed on at least a portion of a leading edge of the blade, the heat exchanger including: a first arcuate panel shaped to conform to the leading edge of the blade; and a second arcuate panel mated with the first arcuate panel; wherein at least one of the first and second arcuate panels includes a channel formed thereon to form a fluid passage between the first and second arcuate panels.

An aircraft blade assembly, including: a blade extending from a blade root to an opposite tip; and a heat exchanger disposed on at least a portion of a leading edge of the blade, the heat exchanger including: a first arcuate panel shaped to conform to the leading edge of the blade; and a second arcuate panel mated with the first arcuate panel; wherein at least one of the first and second arcuate panels includes a channel formed thereon to form a fluid passage between the first and second arcuate panels.