Abstract: An aircraft including a nacelle configured as a housing for an engine and disposed at a fixed location relative a wing member; a proprotor housing coupled to the nacelle, the proprotor housing configured to selectively rotate between a horizontal orientation and a non-horizontal orientation; a door hingedly coupled to the proprotor housing by a first hinge joint and hingedly coupled to the nacelle by a second hinge joint. An aspect includes an aircraft with a proprotor coupled to a wing member, the proprotor comprising a forward portion and an aft portion; wherein the forward portion is configured to selectively pivot between a horizontal orientation and a non-horizontal orientation about a conversion axis C; and wherein when the forward portion is in a non-horizontal orientation, the aft portion is in a horizonal orientation.

Abstract: An aircraft including a nacelle configured as a housing for an engine and disposed at a fixed location relative a wing member; a proprotor housing coupled to the nacelle, the proprotor housing configured to selectively rotate between a horizontal orientation and a non-horizontal orientation; a door hingedly coupled to the proprotor housing by a first hinge joint and hingedly coupled to the nacelle by a second hinge joint. An aspect includes an aircraft with a proprotor coupled to a wing member, the proprotor comprising a forward portion and an aft portion; wherein the forward portion is configured to selectively pivot between a horizontal orientation and a non-horizontal orientation about a conversion axis C; and wherein when the forward portion is in a non-horizontal orientation, the aft portion is in a horizonal orientation.

Abstract: An aircraft including a nacelle disposed at a fixed location relative a wing member; a proprotor housing coupled to the nacelle, the proprotor housing configured to selectively rotate between a horizontal orientation and a non-horizontal orientation; a door pivotably coupled to the proprotor housing; and a linkage to connect the door and the nacelle, the linkage configured to move with the door from a closed position when the proprotor housing is in a horizontal orientation to an open position when the proprotor housing is in a non-horizontal orientation. In some embodiments, there can be a hinge member for hingedly coupling the door to the proprotor and/or nacelle. In other embodiments, the door includes a flexure portion. In some embodiments, the nacelle includes a plurality of doors. In other embodiments, proprotor includes a forward portion and a stationary aft portion; wherein the forward portion is configured to selectively pivot.

Abstract: A door roller mechanism for cooperation with a roller track including a carriage member having a door attachment feature; at least one roller disposed for rotation on a first side of the carriage member when the carriage member moves in the rolling direction; at least one roller disposed for rotation on an opposite second side of the carriage member when the carriage member moves in the rolling direction; a first rub member disposed on the first side of the carriage; a second rub member disposed on the second side of the carriage; and at least one biasing element disposed on the carriage member for resiliently biasing the first rub member and the second rub member in opposite lateral directions so as to contact a respective first track surface and a second track surface in a manner to dampen lateral vibration of a door connected to the roller mechanism.

Abstract: A door track assembly for cooperation with a door roller mechanism, including a housing having a longitudinal channel along a length of the housing, wherein the channel descends at an end of the housing to form a stowage recess for the door roller mechanism, and a first track and a second track that are disposed on the housing along a length of the channel and that descend into the stowage recess and along which the door roller mechanism traverses.

Abstract: An engine mount assembly for coupling an engine to an airframe. The engine mount assembly includes a torsion bar coupled to the engine and a lateral movement control assembly coupled between the torsion bar and the airframe. The lateral movement control assembly includes a spring having a lateral stiffness. The torsion bar rotates in response to lateral movement of the engine such that the lateral movement of the engine is controllable based on the lateral stiffness of the spring.

Abstract: A door track assembly for cooperation with a door roller mechanism, including a housing having a longitudinal channel along a length of the housing, wherein the channel descends at an end of the housing to form a stowage recess for the door roller mechanism, and a first track and a second track that are disposed on the housing along a length of the channel and that descend into the stowage recess and along which the door roller mechanism traverses.

Abstract: A door roller mechanism for cooperation with a roller track including a carriage member having a door attachment feature; at least one roller disposed for rotation on a first side of the carriage member when the carriage member moves in the rolling direction; at least one roller disposed for rotation on an opposite second side of the carriage member when the carriage member moves in the rolling direction; a first rub member disposed on the first side of the carriage; a second rub member disposed on the second side of the carriage; and at least one biasing element disposed on the carriage member for resiliently biasing the first rub member and the second rub member in opposite lateral directions so as to contact a respective first track surface and a second track surface in a manner to dampen lateral vibration of a door connected to the roller mechanism.

Abstract: An aircraft including a nacelle disposed at a fixed location relative a wing member; a proprotor housing coupled to the nacelle, the proprotor housing configured to selectively rotate between a horizontal orientation and a non-horizontal orientation; a door pivotably coupled to the proprotor housing; and a linkage to connect the door and the nacelle, the linkage configured to move with the door from a closed position when the proprotor housing is in a horizontal orientation to an open position when the proprotor housing is in a non-horizontal orientation. In some embodiments, there can be a hinge member for hingedly coupling the door to the proprotor and/or nacelle. In other embodiments, the door includes a flexure portion. In some embodiments, the nacelle includes a plurality of doors. In other embodiments, proprotor includes a forward portion and a stationary aft portion; wherein the forward portion is configured to selectively pivot.

Abstract: An engine mount assembly for coupling an engine to an airframe. The engine mount assembly includes a torsion bar coupled to the engine and a lateral movement control assembly coupled between the torsion bar and the airframe. The lateral movement control assembly includes a spring having a lateral stiffness. The torsion bar rotates in response to lateral movement of the engine such that the lateral movement of the engine is controllable based on the lateral stiffness of the spring.