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A nacelle for mounting under the wing of an aircraft a turbojet engine unit of the rear contrafan type with a very high by-pass ratio, the engine including a gas generator driving two overlapping contra-rotating turbines integral with ducted contra-rotating propellers downstream of the gas generator

A nacelle for mounting under the wing of an aircraft a turbojet engine unit of the rear contrafan type with a very high by-pass ratio, the engine including a gas generator driving two overlapping contra-rotating turbines integral with ducted contra-rotating propellers downstream of the gas generator. The nacelle includes generally cylindrical inner and outer cowlings defining the secondary flow path containing the propellers, and a mast for suspending the engine unit comprising a pair of arms disposed in the longitudinal vetical axial plane of the engine unit and contained in a fairing, and a horizontal carrier beam fixed to the lower ends of the arms and disposed between the inner cowling and the engine casing. The upper ends of the arms are fixed to a box structure of the wing either directly or through a conventional engine pod suspension mast. In the former case the thickness of the outer cowling is integrated into the thickness of the wing, and the outer side of the cowling merges with the lower wing surface by means of a Karman type profile evolving in a direction from upstream to downstream in such a manner that, in an axial longitudinal plane vertically through the longitudinal axis of the engine unit, the generatrix defining the inner side of the outer cowling is overall tangential to the lower wing surface. The inner and outer cowlings are each divided into 120°sectors, the lower two of which can be pivoted outwards and upwards to simplify maintenance.

대표청구항 ▼

A nacelle for a turbojet by-pass engine unit of the rear contrafan type including a gas generator, two overlapping free contra-rotating turbines driven by said gas generator, an engine casing surrounding said gas generator and said turbines, and two ducted contra-rotating propellers rigid with said

A nacelle for a turbojet by-pass engine unit of the rear contrafan type including a gas generator, two overlapping free contra-rotating turbines driven by said gas generator, an engine casing surrounding said gas generator and said turbines, and two ducted contra-rotating propellers rigid with said turbines downstream of said gas generator and disposed in a cold flow path of the engine unit outwardly of said engine casing, said nacelle mounting said turbojet engine unit under the wing of an aircraft and comprising: an inner cowling of generally cylindrical shape surrounding said engine casing and forming the inner wall of said cold flow path, said inner cowling being openable to provide access to said engine, an outer cowling which is also of generally cylindrical shape and which has an inner side defining the outer wall of said cold flow path and an outer side forming the exterior of the nacelle, a mast for suspending said turbojet engine unit, said mast comprising two arms disposed in a vertical plane containing the longitudinal axis of said turbojet engine unit, said arms having upper and lower ends, and a fairing containing said arms, joining means for connecting said upper ends of said arms to a box structure of said aircraft wing, and a horizontal carrier beam disposed longitudinally between said engine casing and said inner cowling, said carrier beam being rigidly connected to said lower ends of said arms wherein said outer cowling is divided into three 120°sectors, one of said sectors being disposed uppermost and symmetrically relative to an axial vertical longitudinal plane of the turbojet engine unit and each of said sectors extend from a front portion to a rear portion of said outer cowling, and wherein two lateral sectors of said outer cowling comprise movable cowls which can be pivoted laterally about longitudinal pivot hinges fixed on said upper sector and wherein longitudinal edge portions of said lateral sectors can be connected together at a bottom portion thereof in a closed position and said outer cowling includes an annular retaining structure.