GB2069427A

GB2069427A - Aircraft powerplant housings

Info

Publication number: GB2069427A
Application number: GB8104327A
Authority: GB
Original assignee: British Aerospace PLC
Current assignee: BAE Systems PLC
Priority date: 1981-02-12
Filing date: 1981-02-12
Publication date: 1981-08-26
Also published as: GB2069427B

Abstract

A powerplant housing assembly 2 for mounting a powerplant 1 on a part of an aircraft body which assembly comprises a main body portion 3, and a ducted extension body portion 30 pivotally attached at 11 to the main body portion 3. The main body portion has a longitudinal bore adapted to receive a powerplant 1 and guide means 22/20 which guide the powerplant into and out of the bore. The ducted extension body portion 30 may be pivoted from a position in which it blends with the main body portion 3 to the position shown to allow the insertion of a powerplant into the bore. Guide means 22/20 comprises rollers 22 on the powerplant into the bore. Guide means the inside of body portion 3. The whole assembly may pivot about 16 for thrust restoring in V/STOL aircraft. In this case, a lip portion (Fig. 1, not shown) at the front of the extension body 30 may be tilted downwards to align it with the free stream when the assembly is tilted. <IMAGE>

Description

SPECIFICATION Aircraft powerplant housings This invention relates to housings for aircraft powerplant; it has for an objective the provision of a housing which facilitates the quick and easy removal and installation of a powerplant. A further objective is the convenient attachment of the housing to an aircraft in such a manner that the efflux of the powerplant may be directed rearwardly, downwardly or a combination of both.

In this specification, those terms relating to relative disposition of components such as, upward, downward, forward, rearward, relate to the housing attached to an aircraft when that aircraft is in a straight and level flight attitude and when the efflux is directed rearwardly, that is to say, as drawn.

According to this invention, there is provided a powerplant housing assembly including a main body portion, and a ducted extension body portion, the main body portion having an intake end, an exhaust end, a longitudinal bore extending between the two ends, and guide means, said longitudinal bore being adapted to receive a powerplant, one of the intake end and the exhaust end being adapted to allow the insertion or withdrawal of the powerplant to or from said bore, said guide means allowing the powerplant to be guided into or out of said bore through said one end, the ducted extension body portion being attached to the one end for pivotal movement between a position in which the extension and main body portions together define a substantially continuous intermediate surface region and a position in which the ducted extension body portion is clear of said one end to allow the insertion or withdrawal of the powerplant to or from said bore.

The guide means of the main body portion preferably is one of the associated parts of a guide assembly comprising track means and track following means, the other of the associated parts being attached to the powerplant.

The intake end of the main body portion advantageously is adapted to receive the powerplant and the ducted extension body portion is pivotally attached to the intake end.

The ducted extension body portion may include a forward tiltable portion which can at least partially be aligned with the free airstream when the longitudinal axis of the body means lies at an angle to the free airstream.

The powerplant housing assembly preferably includes attachment means by which the assembly is attachable to an aircraft structure.

For a vertical or short take-off aircraft the attachment means advantageously is in the form of a pivot which allows the assembly to be tilted with respect to the aircraft structure.

In the case where the powerplant housing assembly pivotally depends from an aircraft wing, at least part of the upper surface of the powerplant housing forward of the pivot is preferably continuous with the neighbouring upper surface of the wing when the aircraft is in normal flight.

One embodiment of a powerplant housing is described by way of example with reference to the accompanying drawings, in which: Figure 1 is a side elevation in which the housing is both connected to an aircraft wing and has a powerplant installed, Figure 2 is a similar view to that of Figure 1 but with a powerplant in the process of being installed or removed, Figure 3 is a plan view on Arrow Ill of Figure 1, Figure 4 is a cross sectional view upon Arrows IV--IV of Figure 1, Figure 5 is a cross sectional view upon Arrows V-V of Figure 1, Figure 6 is a cross sectional view upon Arrows VI--VI of Figure 1, and Figure 7 is an enlarged cross sectional view of that region in circle VII of Figure 1.

In the drawings, an aircraft powerplant, in this case a jet propulsion engine 1 with an axis of rotation X-X is housed within a housing assembly 2. The housing assembly is formed about a longitudinal axis coincident with that referenced X-X. As drawn both axes lie horizontal, but as to be described below, they can be tilted to direct the engine exhaust efflux downwards.

The housing assembly itself includes a body 3 of hollow generally cylindrical shape with an intake end 4 and an exhaust end 5. The main structure of the body includes a longitudinally extending beam 6 lying symmetrically along the axis X-X when viewed in plan at the top of the cylindrical shape, and two cross members rigidly connected to the beam. The front cross member, referenced 7, has arms 8 depending from each lateral extremity, each arm having an attachment point 12 to which engine mounting links 13 are attached. The cross member 7, further, carries a tubular bearing 9 mounted upon a universally swivelling arrangement to accept an engine mounting spigot 10 protruding vertically upwards from the engine, and a forwardly directed pair of pivot lugs 11 , the function of which will be described below.

The rear cross member, referenced 14, also has arms 1 5 depending from each laterai extremity, and an upwardly directed pair of pivot brackets 1 6 to which reference will be made below. It also carries, one upon each arm 15, gimbal mounted nut members 1 7 which form part of twin screw jacks for housing assembly tilting purposes.

The beam 6 protrudes rearwardly of the rear cross member 14 and its aft extremity carries a lug 1 8 to which rear mountings 1 9 of the engine are attached.

The body 3 further incorporates twin spaced tracks 20, one along each side approximately in the same plane as the X-X axis. The tracks are built in to load bearing side walls 21 of the body. It is with these tracks that rollers 22 carried by the engine 1 engage so that the engine is supported as it is guided into and out of the body along its axis X-X. A trolley 23, not being part of the invention, is arranged to carry the engine when the rollers 22 move out of register with their associated tracks. Figure 2 illustrates this condition. The pair of pivot brackets 1 6 connect with pivot pin means, not shown, carried by the aircraft wing, shown generally at 24, so that the housing assembly can pivot about a generally spanwise axis.Such pivotal movement is effected by twin screw jacks, the nut members 17, to which reference has already been made, being gimballed to the arms 1 5 and their associated screw members 25 being pivoted to pivot brackets 26 carried by the wing. Rotation of the screw members effects tilting movement of the housing assembly 2 from the position illustrated in which the efflux is directed rearwardly to a position or positions in which the efflux from the engine is directed at least partially downwards. If such tilting of the housing assembly is not required, the housing assembly is fixedly attached to the wing; the brackets 1 6 and 26 are replaced by rigid connections and the twin screw jacks (17, 25) are eliminated.

At the exhaust end 5 of the body 3 is mounted an outlet structure 27, which has an annular leading flange 28 to be described with reference to Figure 7. The outlet structure 27 contains an exhaust duct and a propulsion nozzle through which the propulsion efflux flows. Conveniently, the engine itself carries any reheat equipment on its rear end; this is shown for reference at 29.

At the inlet end 4 of the body 3 is carried an inlet structure 30 which contains an inlet duct through which the engine is aspirated. The inlet structure 30 is pivoted by means of the pivot lugs 11 to the body 3 so that it can be swung upwardly as shown in Figure 2 to clear an emerging or reentering engine. The structure 30 has rearwardly extending arms 31 to connect with the lugs 11.

The swinging movement is effected by means of jacks 32, Figure 2.

The inlet structure 30 further includes "blow in" doors 33 for additional airflow and also a tilting annular lip portion 34 (Figure 1) which can be tilted to be more closely aligned with the free airstream when the housing assembly 2 is itself tilted with reference to the wing 24. Tilting is effected by means of a jack 35.

As before referenced, the outlet structure includes a leading annular flange 28. When the engine is installed in the housing assembly this flange 28 is engaged by annular seals 36, 37 carried by an aft annular flange 38 of the engine.

In effect the engine plugs into the outlet structure as the engine is moved rearwardly to its fully installed position along the tracks 20. The components 36, 37, and 38 are illustrated in Figure 7.

A dismountable power take-off shaft arrangement (not shown) can extend from the engine to aircraft mounted ancilliary equipment through the spigot 10 and the tubular bearing 9.

Claims

1. A powerplant housing assembly including a main body portion, and a ducted extension body portion, the main body portion having an intake end, an exhaust end, a longitudinal bore extending between-the two ends, and guide means, said longitudinal bore being adapted to receive a powerplant, one of the intake end and the exhaust end being adapted to allow the insertion or withdrawal of the powerplant to or from said bore, said guide means allowing the powerplant to be guided into or out of said bore through said one end, the ducted extension body portion being attached to the one end for pivotal movement between a position in which the extension and main body portions together define a substantially continuous intermediate surface region and a position in which the ducted extension body portion is clear of said one end to allow the insertion or withdrawal of the powerplant to or from said bore.

2. A powerplant housing as claimed in Claim 1, wherein the guide means of the main body portion is one of the associated parts of a guide assembly comprising track means and track following means, the other of the associated parts being attached to the powerplant.

3. A powerplant housing assembly as claimed in Claim 1 or Claim 2, wherein the intake end of the main body portion is adapted to receive the powerplant and the ducted extension body portion is pivotally attached to the intake end.

4. A powerplant housing assembly as claimed in Claim 3, wherein the ducted extension body portion includes a forward tiltable portion which can at least partially be aligned with the free airstream when the longitudinal axis of the body means lies at an angle to the free airstream.

5. A powerplant housing assembly as claimed in any of the preceding claims, which further includes attachment means by which the assembly is attachable to an aircraft structure.

6. A powerplant housing assembly as claimed in Claim 5, wherein the attachment means is in the form of a pivot which allows the assembly to be tilted with respect to the aircraft structure.

7. A powerplant housing assembly according to Claim 6 which pivotally depends from an aircraft wing, at least part of the upper surface of the powerplant housing forward of the pivot being continuous with the neighbouring upper surface of the wing when in normal flight.

8. A powerplant housing assembly substantially as hereinbefore described with reference to, and as illustrated in, any of the accompanying drawings.