GB2528116A

GB2528116A - Aircraft engine and wing assembly

Info

Publication number: GB2528116A
Application number: GB1412349.1A
Authority: GB
Inventors: David Campbell Bannerman
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-07-11
Filing date: 2014-07-11
Publication date: 2016-01-13
Also published as: GB201412349D0

Abstract

An aircraft engine 1, for mounting on an aircraft wing, comprises a fan or propeller 7 attached to an axial shaft 3. The fan or propeller comprises a plurality of blades 16 arranged around the shaft of which at least one has an internal channel. The axial shaft has an internal channel formed therein that extends from an opening 15 at a front end towards, and in communication with, the channel in the blade(s). The opening can be selectively opened and closed so that air is received into the shaft channel when open and is diverted through the internal channel of the blade(s) and exhausted through a further opening. The channelled air is used for blowing over the surface of an aircraft wing to enhance lift at lower airspeeds.

Description

Aircraft Engine and Wing Assembly

Field of the Invention

The present invention relates tc an aircraft engine and also to a wing assembly for an aircraft and related lift devices.

Background of the Invention

Conventional aircraft lift is produced by a lower pressure being created on the upper surface of the craft's wing relative to the pressure on the lower surface. The special shape of the wing is such that air flowing over the upper surface has to travel a greater distance (and therefore faster) than the air flowing underneath. This creates the reguired pressure difference that lifts the wing upwards. The engines produce the thrust that moves the aircraft in a particular direction tc cause the air to flow over and below the wing surfaces.

Typically when the aircraft is flying close to the ground, the aircraft needs to travel at a lower airspeed in crder to be able to safely manoeuvre in what can be a crowded airspace (and also to be able to take-off and land at a safe speed) For this purpose, the effective surface area of the wings is increased by deploying retractable flaps. The effect of the increased surface area is to increase the lift for a given airspeed. This is at the expense of aerodynamic performance, and hence the flaps are retracted as the airspeed is increased for higher altitude flying.

Even with the use of flaps (or similar adjustable control surfaces) there is a limit on the amount of additional lift that can be created, and it would be desirable to be able to selectively generate additional lift for short take-off and landing procedures and/or low-speed rnanoeuvring in general and /or cruising altitudes.

Summary of the Invention

A first aspect of the invention provides an aircraft engine for mounting on an aircraft wing, the engine comprising a fan or propeller mounted on an axial shaft, the fan or propeller comprising a plurality of blades arranged around the shaft of which at least one has an internal channel, the axial shaft having an internal channel formed therein that extends from an opening at a front end towards, and in communication with, the channel in the blade(s), which opening can be selectively opened and closed so that, in use, air is received into the shaft channel when open and is diverted through the internal channel of the blade(s) and exhausted through an opening.

Such an engine acts to divert a fraction of the intake air through the blade(s) to a position where it can be diverted over part of a wing surface to enhance lift. The selective nature of the opening and closing enables an operator (or automatic controller even) to open this form of elevator control system when on or near the ground, trading off thrust for additional lift. When higher altitude is reached, the system can be closed to use all of the intake air for thrust.

At cruising altitude, the system can additionally be used to provide lift in thinner air, and on descent, for additional, more efficient lift when flaps are down and corrections from the glide path are needed.

Usually, the engine will be mounted beneath a wing, and hence the air in this case will be diverted radially outwards and exhausted upwardly over the wing.

The engine can be used with any type of aircraft, including airplanes, helicopters, drones, and the like. The engine can be a gas turbine (jet) engine, a propeller engine, or a turbo-propeller engine.

The internal channel of the blade(s) can extend to an opening located at or in the region of the distal end of the blade(s), e.g. i.e. near their tips. In some embodiments, the blade opening can be nearer the proximal end, close to the hub, depending on the location of the engine relative to the wing.

The shaft opening can be selectively opened and closed by means of a cover mounted on a linking arm that passes through the internal channel of the axial shaft to an actuator effective to control the position of said cover. The actuator may be configured to move the oover baok and forth along the shaft axis to close and open the shaft opening.

The engine may include a casing or cowling that oiroumferentially surrounds at least part of the engine, including the distal ends of the fan or propeller blades, the casing having formed therein an aperture located generally adjacent to the position of the blade distal ends such that, in use, air exhausted through the blades passes through the aperture. In cases where the engine is to be mounted directly beneath a wing, the aperture will be in the upper position.

Where the engine is a gas turbine engine, said fan or propeller may be aft of a further, front fan or propeller stage through which the shaft channel passes to its front opening.

Where the engine is a propeller engine, the internal channel of the propeller blade(s) may extend to an opening located on a rear surface of the blade, either or both at proximal and distal locations relative to the axial shaft.

A second aspect provides a turbo-propeller type engine comprising a propeller linked to a fan on respective axial shafts, each of the propeller and fan having a plurality of blades arranged around its shaft at least one of which has an internal channel, the respective axial shafts each having an internal channel formed therein extending from an opening at a front end towards, and in communication with, the channel in the blade(s) carried by said shafts, which opening can be selectively opened and closed so that, in use, air is received into each shaft channel when both open so that this air is diverted to the blades of both the propeller and fan blade(s) and exhausted through an opening A third aspect provides an aircraft wing assembly comprising a wing having an engine of any preceding definition mounted relative to it in such a way that in use the air exhausted through the blade(s) travels over at least part of the wing's upper surface.

A fourth aspect provides an aircraft wing assembly comprising a wing having one or more vents formed therein extending between the upper and lower surfaces of the wing, and an engine according to any preceding definition which is mounted beneath the wing lower surface in such a way that air exhausted through the blade(s) travels through the vents and over at least part of the wing's upper surface.

The or each vent may be arranged to be selectively opened and closed. Plural vents may be provided in the form of a grid wherein the vents slide open and shut, e.g. sideways.

The or each vent may be arranged to be selectively opened and closed in conjunction with the engine front opening and closing.

Brief Description of Drawings

The invention will now be described, by way of non-limiting example, with reference to the accompanying drawings, in which: Figure 1 is a partial cut-away view of a gas-turbine engine according to the invention; Figure 2 shows views of the engine of Figure 1 mounted to a wing and also a wing vent; Figure 3 is a side sectional view of a turbo-propeller engine according to the invention; Figure 4 is a side sectional view of a propeller engine according to the invention; Figure 5 is a close up view of part of the propeller engine in different configurations; Figure 6 is a perspective view of a helicopter rotor mounted to an engine with a small wing, and an additional rotor design according to the invention; Figure 7 is a novel kind of aircraft comprising first and second wing sections for short take-off and landing, beneath which are mounted an engine according to the invention; and Figure 8 is a side-sectional view of an alternative type of air inlet mechanism.

Detailed Description of Preferred Embodiments

Embodiments herein relate to an aircraft engine and also to wing or rotor blade assemblies of aircraft that, together with such an engine or engines, act to generate in a selective way additional lift to the aircraft, i.e. additional to that provided by the wings and control surfaces alone. Generally speaking, this is achieved using a nonheated air channelling system by which the engine includes an air intake that can be selectively opened and closed; when opened, a fraction of the nonheated air entering the fore end of the engine is diverted through a channel within the engine and released at such a position that this exhausted high-speed air passes above the wing to generate additional lift.

The result is that enhanced lift can be selectively provided to the aircraft as and when the controller (be it a pilot or an automated system) requires. For example, having extra lift at low speeds is generally desired when the aircraft is close to the ground, particularly when landing and taking off.

Embodiments provide this by trading off some of the air used for thrust and diverting it over the wings to enhance lift.

The system may permit landing and take-off at shorter or very short distances, possibly even on maritime aircraft carriers, more efficient cruising at high altitude, and also in emergency situations where a sudden increase in lift is required.

In some embodiments, vents are provided in the wings to allow air from the underlying engine or engines to flow through the wing body and over the wing surface, for example through horizontal slits. In some embodiments, these slits may be opened and closed when required.

The principle can be applied to any type of aircraft engine, including gas turbine (jet) engines, propeller engines and turbo-propeller engines. In the following, a detailed understanding of the well-known operation and structure by which such engines generate thrust, e.g. by gas combustion, is not required. The description will concentrate on those new features which provide the enhanced lift.

Referring to Figure la, a first embodiment provides a jet engine 1. The jet engine 1 comprises a fan shaft 3 that passes through the central axis and is of hollow construction.

The fan shaft 3 carries a conventional first fan stage 5, and a second special fan stage 7. Each fan stage 5, 7 comprises fan blades extending radially outwards from the fan shaft 3.

The fan shaft 3 and fans 5, 7 are enclosed by a cowling 8.

Within the fan shaft is located an elongate inner shaft that extends between an intake actuator II at the rear of the engine 1, and a movable, curved cone 13 at the front. The cone 13 is movable along its central axis by the intake actuator 11 and the linking, inner shaft 9 in order to open or close a front nonheated air intake 15. The cone 13 is shaped at its rear end to plug this intake 15 when in the closed position. The intake actuator II includes a motor which moves the linking inner shaft 9 backwards or forwards in accordance with control commands either to close the front intake 15 or to open it.

In the Figure, the cone 13 is shown in the open position, and the air intake 15 is also open. Figure lb shows the cone 13 and air intake 15 when closed.

When the aircraft is moving forwards dile to engine thrust, and the intake 15 is open, a portion of the nonheated air entering the engine 1 enters the intake and thereafter an air channelling system indicated by the arrows. The other portion of air passes through the jet fans 5, 7 in the conventional way for coxrbustion with fuel.

The air channelling system comprises a chamber in the front portion of the fan shaft 3 (which is blocked part-way by a back wall 26 located just behind the second fan stage 7) and one or more blades 16 of the second fan stage 7.

Significantly, said blades 16 are hollow; that is they have an air channel formed internally along their length with a hole at or near their terminating ends. Thus, the incoming air is diverted through the blades and is exhausted through the blade tips and then through an air outlet 17 in the cowling 8.

Figure 2a shows said jet engine 1 when attached beneath an aircraft wing 19 by a pylon 21. oth wings will in practice support an engine, or engines, e.g. two or four, in this manner. The air intake 15 is shown open. As indicated by the air flow arrows, and particularly in Figure 2b, the nonheated air as it is exhausted through the outlet 17 passes over the wing 19 via slit vents 23 formed through the wing's cross-section near the fore end. Figure 2b shows that each slit vent 23 permits the air exhausted from outlet 17 to pass over the majority of the surface of the wing 19 notwithstanding that the engine 1 is beneath the wing.

The wing slit vents 23 can also be selectively opened and closed. In high speed mode' when the aircraft does not require extra lift, the air intake 15 and the slits vents 23 are closed so that all of the incoming air is used to generate thrust, and the aerodynamic performance of the wing is maximised. The vents 23 may also be opened at cruising altitude to provide extra lift in thinner air and to reduce need for thrust. As the aircraft descends again, the opening of the air intake 15 and vents 23 dissipates some of the thrust and diverts air over the wings to give the extra lift required for landing and manoeuvring for landing.

Figure 2c shows a further embodiment elevation system which is a variation on the previous one, and is comprised of an engine 8' (in this case a jet engine, but it can be of any previously-described type) fixed below a wing 19' that comprises, just above its leading edge, the slit vents 23' through which the exhausted air from the engine 8' is released. Some of this air then passes over the wing surface and other air passes through elongate slit vents where it emerges as shown.

Figure 2d is a cross-sectional view of the assembly shown in Figure 2a and Figure 2e shows the nose 13 when in the closed position. Figure 2f shows the slit vents 23 in the open and shut configurations.

A second embodiment engine will now be described with reference to Figure 3, which shows in cross-section a turbo-propeller (turbo-prop) engine 40. As will be appreciated, a turbo-prop engine comprises a front propeller stage 41 and a rear gas turbine stage 42, the two stages being connected by a gear 44. The gas turbine stage 42 rotates a fan and applies this rotation through gears 44 to rotate a propeller 43 which generates thrust sufficient to enable flight.

The engine 40 is shown mounted below a wing 46 by means of a pylon 47. The cowling of this engine 40 is indicated by reference numeral 48. Each of the two engine stages 41, 42 operate along the same lines as that of the first embodiment; each stage employs a selectively movable nose cone 50, 52 which opens and closes respective nonheated air channels that extend partly through the axial shafts carrying respective fans and then upwards through hollow fan blades 54, 56 as before.

The nose cones 50, 52 are controlled by a single actuator 45 in this case so that opening and closing occurs simultaneously.

First and second air outlet channels 60, 62 are formed directly above the terminating ends of the respective fan blades 54, 56, in order to receive exhausted air. These channels 60, 62 extend within the cowling 48 and wing 46.

Within the wing 46, the two channels 60, 62 merge into a single channel 64 which exhausts the air to a wing vent 65 on the wing's upper surface.

This embodiment therefore makes use of both engine stages of a turbo-prop engine 40 to generate extra lift.

A third embodiment will now be described with reference to Figures 4a and 4b which show in cross-section a propeller engine 80 connected beneath a wing 82 by a pylon.

Within a cowling of the engine 80 is the drive mechanism 88 that generates in the conventional way rotational force applied to a propeller 92. An intake actuator 91 is, like previous embodiments, connected by a linking shaft 90 to a nose cone 98 in order to move it axially back and forth to close and open an air inlet. The propeller 92 itself comprises a hub 96 on which is mollnted a plurality of blades 94 that are shaped in the conventional manner, but which have a hollow interior that extends to one or more outlets 100 to the rear side of said blades. In Figure 4a, each blade 94 has a proximal outlet (nearest to the hub 96) and a distal outlet nearest to the tip. Thus, when the intake actuator 91 opens the air inlet (i.e. in the position shown in Figure 4a) incoming nonheated air passes through a propeller blade 94 and over the wing via the or each outlet 100, as indicated by the arrows.

As shown more clearly in Figure 4b, a screw-like diverter 102 is provided behind the oone and is fixed so as to be static relative to the propeller 92 at an angle to ensure that incoming air is diverted upwardly and not downwards.

Figure 5a shows & modified version of the third embodiment in that a strengthening sleeve 110 is provided at the proximal part of the propeller blade 94 and only one outlet 112 is provided on each blade, which extends through this sleeve.

Figure Sb shows another modified version, which is similar to the Figure 5 version but has a second outlet 114 near the tip of each blade 94.

The same principle can be applied to other forms of aircraft including helicopters and drones. Figure 6 shows a helicopter 121 using a fourth embodiment engine system 120 which employs two said engine systems. Each engine system 120 comprises a jet or other type of engine 122 mounted beneath a respective short wing 123. Each short wing 123 has one or more elongate slit vents 125 fed with unheated air from the engine 122 as before. The helicopter 121 has a top-mounted rotor assembly comprised of a central hub 130 from which project radial blades 128. In use, unheated air flows just over the short wings 123 for additional lift. At higher speeds, the rotor blades 128 provide more thrust than lift, with the wings 123 providing most of the lift, enhanced by the vents 125 increasing overall speeds.

As shown in Figure 6(b) in a still further embodiment the central hub 130 may be fed with the unheated air from the or each engine system 120 which then passes outwards through hollow rotor blades 128 for it to be expelled at apertures provided at the tips. This reduces the vortex effect at the tip of the blades.

In operation, in both cases, the engine 122 operates as before to selectively open and close the nose cone and thereby (when open) draw a fraction of the intake air inwards and upwards where it is exhausted over the short wings 123.

Figure 7 shows such a variation of the Figure 6 elevation system mounted this time on an aircraft 160 which is a new type of airplane-helicopter hybrid in that it comprises the engines 162, flat air vents 164 through which air from the engine is channelled, and a rear rotor 166, but without conventional main helicopter rotor blades. The aircraft 160 is capable of very short take-off and landing operations, similar to a helicopter except it does not offer vertical take offs and hovers. Mi emergency parachute mechanism 168 is also provided for engine or lift failures.

Figure 8 shows an alternative air inlet control unit 180 which can be used in any previously-described embodiment, and in this case permits diversion of the incoming nonheated air both above and below, i.e. in multiple directions. Instead of moving the nose cone 182 forwards, the cone is moved inwards/backwards by an actuator 184 and linking arm 185 relative to an outer sleeve 186.

In summary, there is disclosed a number of aircraft engines and arrangements, of such engines below aircraft wing assemblies that together act to provide in a controlled way enhanced lift to an aircraft through adaptations to conventional designs, and including a new hybrid aircraft-helicopter design. The general principle is to divert some incoming high speed, nonheated air to a position that allows it to flow over the wing's upper surface to increase lift.

This is by means of channelling, which starts with a valve mechanism at the front of the engine which can be selectively opened and closed by an operator or control system to draw nonheated air-in (when open) or to use all of the air for thrust (when closed) . The actuation system controlling the valve may consist of a motor that moves a cone between the open and closed positions. The actuation system would typically be enabled at take-off where maximun lift is reguired a relatively low speed. The system may be disengaged when sufficient height and speed is reached so that all intake air is used for thrust. The system may be enabled again during cruising, if required, to provide greater lift at less thrust in thinner air conditions. It may also be engaged again during descent to permit reduction in thrust and increase in lift for a more controlled descent and landing, and be used for manoeuvring off the glide path as necessary where thrust is required.

In theory, the above-described arrangements can be used for: Very Short Take Off and Landing (VSOL) operation whereby some engine power is used to provide bonus lift for take-off and landing.

Maritime aircraft carrier operation to allow a conventional aircraft to land on their short decks, with less need for catapult or ski jump launches or arrestor wires for landing, or to allow heavier payloads or fuel reserves to be carried.

Emergency avoidance to permit the pilot or an automated system to enable the system in situations where a rapid ascent is required.

It will be appreciated that the above described embodiments are purely illustrative and are not limiting on the scope of the invention. Other variations and modifications will be apparent to persons skilled in the art upon reading the present application.

Moreover, the disclosure of the present application should be understood to include any novel features or any novel combination of features either explicitly or implicitly disclosed herein or any generalization thereof and during the prosecution of the present application or of any application derived therefrom, new claims may be formulated to cover any such features and/or combination of such features.

Claims

CLAIMS1. An aircraft engine for mounting on an aircraft wing, the engine oomprising a fan or propeller mounted on an axial shaft, the fan or propeller comprising a plurality of blades arranged around the shaft of which at least one has an internal channel, the axial shaft having an internal channel formed therein that extends from an opening at a front end towards, and in communication with, the channel in the blade(s), which opening can be selectively opened and closed so that, in use, air is received into the shaft channel when open and is diverted through the internal channel of the blade(s) and exhausted through an opening.
2. The engine of claim 1, wherein the internal channel of the blade(s) extends to an opening located at or in the region of the distal end of the blade(s).
3. The engine of claim 1 or claim 2, wherein the shaft opening is selectively opened and closed by means of a cover mounted on a linking arm that passes through the internal channel of the axial shaft to an actuator effective to control the position of said cover.
4. The engine of claim 3, wherein the actuator is configured to move the cover back and forth along the shaft axis to close and open the shaft opening.
5. The engine of any preceding claim, wherein the engine includes a casing or cowling that circumferentially surrounds at least part of the engine, including the distal ends of the fan or propeller blades, the casing having formed therein an aperture located generally adjacent to the position of the blade distal ends such that, in use, air exhausted through the blades passes through the aperture.
6. The engine of any preceding claim, being a gas turbine engine in which said fan or propeller is aft of a further, front fan or propeller stage through which the shaft channel passes to its front opening.
7. The engine of any one of claims 1 to 5, being a propeller engine.
8. The engine of claim 7, in which the internal channel of the propeller blade(s) extend to an opening located on a rear surface of the blade, either or both at proximal and distal locations relative to the axial shaft.
9. A turbo-propeller-type engine comprising a propeller linked to a fan on respective axial shafts, each of the propeller and fan having a plurality of blades arranged around its shaft at least one of which has an internal channel, the respective axial shafts each having an internal channel formed therein extending from an opening at a front end towards, and in communication with, the channel in the blade(s) carried by said shafts, which opening can be selectively opened and olosed so that, in use, air is received into each shaft channel when both open so that air is diverted to the blades of both the propeller and fan blade(s) and exhausted through an opening.
10. An aircraft wing assembly comprising a wing having an engine of any preceding claim mounted relative to it in such a way that in use the air exhausted through the blade(s) travels over at least part of the wing's upper surface.
11. An aircraft wing assembly comprising a wing having one or more vents formed therein extending along the upper surface of the wing, and an engine according to any preceding claim which is mounted beneath the wing lower surface in such a way that air exhausted through the blade(s) travels through the vents and over at least part of the wing's upper surface.
12. An aircraft wing assembly according to claim 10 or claim 11, wherein the or each vent is arranged to be selectively opened and closed.
13. An aircraft wing assembly according to claim 12, wherein the or each vent is arranged to be selectively opened and closed in conjunction with the engine front opening and olosing.
14. An aircraft comprising opposed first and second wing assemblies according to any of claims 10 to 13.
15. A helicopter aircraft comprising the wing assembly of any of claims 10 to 13.
16. A helicopter aircraft according to claim 15, comprising a rotor assembly located above the wing assembly, which rotor assembly oomprises a central hub and a plurality of rotors extending radially from the hub which are hollow, the hub being arranged in use to receive air from the engine or engines which is channelled through the hollow rotors and expelled through a vent at or near the tip.