Abstract: A replacement tip section for a rotor blade, from which a legacy tip section was removed, includes a blade tip portion configured to be attached to an intermediate section of the rotor blade after removal of the legacy section. The intermediate section has a connection feature at an end of the intermediate section to which the blade tip portion is attachable. The replacement tip section includes a transition region configured to be attached to a forward end of the connection feature. The transition region is configured to form a leading edge of the rotor blade and extends from the blade tip portion to form an opening into which the intermediate section is attached. The transition region includes a first end having a first airfoil that conforms to the intermediate section airfoil at the connection feature, and a second end having a second airfoil that conforms to the blade tip portion.

Abstract: A replacement tip section for a rotor blade, from which a legacy tip section was removed, includes a blade tip portion configured to be attached to an intermediate section of the rotor blade after removal of the legacy section. The intermediate section has a connection feature at an end of the intermediate section to which the blade tip portion is attachable. The replacement tip section includes a transition region configured to be attached to a forward end of the connection feature. The transition region is configured to form a leading edge of the rotor blade and extends from the blade tip portion to form an opening into which the intermediate section is attached. The transition region includes a first end having a first airfoil that conforms to the intermediate section airfoil at the connection feature, and a second end having a second airfoil that conforms to the blade tip portion.

Abstract: A method of mounting a replacement tip section to an exposed end of a rotor blade includes removing an existing tip section from the rotor blade to create the exposed end of the rotor blade, installing the rotor blade having the exposed end onto a holding fixture, assembling the replacement tip section about the exposed end of the rotor blade, positioning a bonding fixture about the replacement tip section, and curing the replacement tip section to the exposed end of the rotor blade.

Abstract: A method of mounting a replacement tip section to an exposed end of a rotor blade includes removing an existing tip section from the rotor blade to create the exposed end of the rotor blade, installing the rotor blade having the exposed end onto a holding fixture, assembling the replacement tip section about the exposed end of the rotor blade, positioning a bonding fixture about the replacement tip section, and curing the replacement tip section to the exposed end of the rotor blade.

Abstract: A rotor blade for a rotary wing aircraft and a tip for the rotor blade. The rotor blade includes a blade root, a blade tip and a blade body that extends from the blade root to the blade tip. The blade tip includes: a continuously swept leading edge, a compound trailing edge, and a continuous anhedral.

Abstract: A replacement tip section for a rotor blade, from which a legacy tip section was removed, includes a blade tip portion configured to be attached to an intermediate section of the rotor blade after removal of the legacy section. The intermediate section has a connection feature at an end of the intermediate section to which the blade tip portion is attachable. The replacement tip section includes a transition region configured to be attached to a forward end of the connection feature. The transition region is configured to form a leading edge of the rotor blade and extends from the blade tip portion to form an opening into which the intermediate section is attached. The transition region includes a first end having a first airfoil that conforms to the intermediate section airfoil at the connection feature, and a second end having a second airfoil that conforms to the blade tip portion.

Abstract: An exhaust system for reducing infrared emissions of a rotary wing aircraft includes a duct assembly having an inlet portion and an outlet portion; the inlet portion configured to receive exhaust from an engine of the aircraft; and the outlet portion coupled to the inlet portion, the outlet portion having an outlet duct with an outlet opening, the outlet duct configured expel an emission containing engine exhaust proximate to a tail fairing of the rotary wing aircraft.

Abstract: A method of mounting a replacement tip section to an exposed end of a rotor blade includes removing an existing tip section from the rotor blade to create the exposed end of the rotor blade, installing the rotor blade having the exposed end onto a holding fixture, assembling the replacement tip section about the exposed end of the rotor blade, positioning a bonding fixture about the replacement tip section, and curing the replacement tip section to the exposed end of the rotor blade.

Abstract: Embodiments of the invention include a vehicle including an engine and a rotor including a plurality of rotor blades in a path of exhaust from the engine. The vehicle includes a rotor control assembly configured to connect the rotor to a rotation force source to rotate the rotor and configured to rotate the rotor at a prescribed minimum rotation rate greater than zero based on at least one of disengaging the rotor from the rotation force source and receiving a control signal to disengage the rotor from the rotation force source. The rotor control assembly is designed to rotate the rotor at the prescribed minimum rotation rate based on at least one system attribute of the vehicle that is affected by a rotation rate of the rotor.

Abstract: An exhaust system for reducing infrared emissions of a rotary wing aircraft includes a manifold; an opening in the manifold, the opening configured to face upwards and away from the rotary wing aircraft; and a chimney including a wall positioned about the opening, the chimney configured to eject an emission of intermixed secondary air and engine exhaust upwards and away from the rotary wing aircraft.

Abstract: An exhaust cooling arrangement includes a first duct having a first inlet and a first outlet, a fairing positioned radially outwardly of the first duct defining an annular space between the fairing and the first duct, and a second duct having a second inlet and a second outlet, the second inlet being positioned upstream of the first outlet within the annular space such that fluid within the annular space can flow along an inside surface of a wall defining the second duct and an outside surface of the wall, upstream being defined by a direction of fluid flow through the annular space.

Abstract: A device for altering infrared signature of an exhaust duct includes a housing configured to attach to an exhaust duct of a vehicle and at least one body attached to the housing at opposing ends of the at least one body, an opening in at least one of the opposing ends being in fluidic communication with a cavity within the at least one body such that fluid can flow into the cavity through the opening.

Abstract: A rotor blade for a rotary wing aircraft and a tip for the rotor blade. The rotor blade includes a blade root, a blade tip and a blade body that extends from the blade root to the blade tip. The blade tip includes: a continuously swept leading edge, a compound trailing edge, and a continuous anhedral.

Abstract: An exhaust infrared signature reduction arrangement includes an exhaust duct, a first vane support disposed within the exhaust duct and a second vane support disposed within the exhaust duct downstream from the first vane support. The first vane support and the second vane support are movable between a first configuration and a second configuration.

Abstract: Embodiments of the invention include a vehicle including an engine and a rotor including a plurality of rotor blades in a path of exhaust from the engine. The vehicle includes a rotor control assembly configured to connect the rotor to a rotation force source to rotate the rotor and configured to rotate the rotor at a prescribed minimum rotation rate greater than zero based on at least one of disengaging the rotor from the rotation force source and receiving a control signal to disengage the rotor from the rotation force source. The rotor control assembly is designed to rotate the rotor at the prescribed minimum rotation rate based on at least one system attribute of the vehicle that is affected by a rotation rate of the rotor.

Abstract: An exhaust infrared signature reduction arrangement includes an exhaust duct having a plurality of holes through a wall of the exhaust duct, and a housing surrounding at least a portion of the exhaust duct defining a cavity between the exhaust duct and the housing.

Abstract: An exhaust system for reducing infrared emissions of a rotary wing aircraft includes an exhaust duct having a fore end for connection with an aft turbine section of an engine of the rotary wing aircraft, the exhaust duct having an aft end having an exhaust opening to expel engine exhaust proximate to a tail fairing of the rotary wing aircraft; and a drive shaft collocated with the exhaust duct, the drive shaft configured to provide rotational force to an aft propeller of the rotary wing aircraft.

Abstract: An exhaust system for reducing infrared emissions of a rotary wing aircraft includes a duct assembly having an inlet portion and an outlet portion; the inlet portion configured to receive exhaust from an engine of the aircraft; and the outlet portion coupled to the inlet portion, the outlet portion having an outlet duct with an outlet opening, the outlet duct configured expel an emission containing engine exhaust proximate to a tail fairing of the rotary wing aircraft.

Abstract: An exhaust system for reducing infrared emissions of a rotary wing aircraft includes an exhaust duct having a fore end for connection with an aft turbine section of an engine of the rotary wing aircraft, the exhaust duct having an aft end having an exhaust opening to expel engine exhaust proximate to a tail fairing of the rotary wing aircraft; and a drive shaft collocated with the exhaust duct, the drive shaft configured to provide rotational force to an aft propeller of the rotary wing aircraft.

Abstract: An exhaust system for reducing infrared emissions of a rotary wing aircraft includes a manifold; an opening in the manifold, the opening configured to face upwards and away from the rotary wing aircraft; and a chimney including a wall positioned about the opening, the chimney configured to eject an emission of intermixed secondary air and engine exhaust upwards and away from the rotary wing aircraft.