IL129948A - Device for anchoring a releasable load to a stationary or airborne launch platform - Google Patents

Description

oom ικ yiip nwvy ^m? τηη>νΛ> y .n IV ^D ni^y!? -pvyoa DEVICE FOR ANCHORING A RELEASABLE LOAD TO A STATIONARY OR AIRBORNE LAUNCH PLATFORM DEVICE FOR ANCHORING A RELEASABLE LOAD TO A STATIONARY OR AIRBORNE LAUNCH PLATFORM Field of the Invention This invention relates to devices for anchoring a releasable load to a launch platform, particularly, but not exclusively, to an airborne platform. It particularly relates to devices for anchoring a releasable load, such as a bomb, missile or rocket, on the underside of an aircraft and releasing the same, while eliminating or minimizing the disturbance which could be caused by the device in the aerodynamic behavior of the released load after its release.

Background of the Invention Military aircraft often carry a releasable load, such as a bomb, and comprise means for releasing it in such a way and at such a position that it will reach a predetermined , target. For this purpose, a support is provided beneath the aircraft's fuselage and releasable couplings are also provided, which comprise cooperating parts carried in the said support and parts carried by the releasable load. Means are provided for opening the couplings when it is desired to release the load at such a time and in such a condition that it will reach the desired target. Obviously, the trajectory followed by the load depends, in each environment, on the direction of motion and the speed of the aircraft at the moment the load is released, on the weight of the load and on its aerodynamic behavior, in particular on the resistance of the air. The resistance of the air will have two components, a vertical one, depending on the weight, dimensions and shape of the load, and a horizontal one, depending on the profile of the load and on the speed of the aircraft at the moment the load is released.

The type of load, with which the invention is particularly concerned, is a bomb, a missile or a rocket, and the type of launch platform is an aircraft, but the invention can be apphed to different types of loads and launch platforms, including stationary ones such as missile launch platforms, and therefore, although particular reference will be made hereinafter, for descriptive purposes, to a bomb or a missile carried on the underside of an aircraft, this should not be construed as limiting the scope of the invention to any extent.

An example of couplings for holding the load beneath the aircraft's fuselage and releasing it, is described in EP-A 0 745 531 Al. Said EP-A is concerned with providing an additional device for stabilizing the releasable load when connected to the aircraft, but it includes a description of conventional coupling means, comprising hooks pivoted to the support member of the aircraft, which can engage rings or loops fixed to the top of the load, whereby to connect the same to the support member beneath the aircraft fuselage, and can disengage themselves from said rings or loops, whereby to release the load.

In every case, the couplings of the prior art comprise elements which project from the upper surface of the load. Obviously said projecting members influence the aerodynamic behavior of the load, particularly in view of the fact that they extend generally perpendicularly to the direction of flight of the aircraft, and therefore somehow affect the transverse profile of the load and the resistance of the air due to the high horizontal component of the speed of the load as it is released from the aircraft. Particularly in the case of a bomb, which does not have independent propulsion means, the aerodynamic influence of such coupling elements can cause the bomb to fall not on the predetermined target, but at a significant distance therefrom. No means are known in the prior art for eliminating or overcoming the aerodynamic influence of such coupling elements.

It is therefore a purpose of this invention to provide devices for coupling a releasable load, particularly a bomb, to the underside of an aircraft fuselage, which do not contribute to the drag of the load, after this has been released.

It is another purpose of this invention to provide such coupling devices which do not include coupling elements fixed to the releasable load, which modify the transverse profile of the load itself, once this has been released.

It is a further purpose of this, invention to provide such coupling devices comprising elements attached to the load, which have an in-flight or carrying position, and are displaced, once the load is released, from said position either by the resistance of the air or by actuating means provided in the load.

It is a still further purpose of this invention to provide a coupling device which comprises releasable couphng elements attached to the load for retaining it in its carrying position, which couphng elements become separated from the load as soon as the same is released.

It is a still further purpose of this invention to provide a coupling device which comprises elements attached to the load for achieving the aforementioned purposes, and additionally, comprises elements for eliminating discontinuities, in particular, recesses, in the surface of the load, which may cause turbulence with undesirable aerodynamic consequences.

Other purposes and advantages of this invention will appear as the description proceeds.

Summary of the Invention Prior art couphng devices for releasably carrying a load by means of an aircraft, comprise first coupling elements housed in a support fixed to the bottom of the aircraft fuselage, cooperating with second coupling elements attached to the load. Hereinafter, for the sake of clarity only, the first couphng elements, which remain connected to the aircraft, will be called "primary", and the second ones, which are carried by the load when this is released, will be called "secondary". This invention requires no innovation in the primary coupling elements, that can be such as described in the aforementioned EP-A 0 745 531 Al, or other, capable of carrying out the same function. An aircraft carrying a releasable externally stored load consisting in a bomb or missile or the like, acts as a launch platform for said cargo and is included in the expression "launch platform" as used herein. Therefore what is disclosed herein for such an aircraft is applicable to any releasable load and any launch platform, whether stationary, such as missile launchers, or mobile, with the modifications that will be obvious in each case to skilled persons.

The coupling device according to the invention comprises, in combination with a primary coupling element attached to the launch platform, at least one secondary coupling element comprising a coupling seat fixed to the load and having an opening, and at least an intermediate coupling member having an aperture adapted to be engaged by a primary coupling element and a hook-like portion adapted to engage the coupling seat, said intermediate member being displaceable from a first position - in which said aperture thereof is engaged by a primary coupling element and said hook-like portion thereof has been inserted through said coupling seat opening and engages said seat, whereby said intermediate member connects said primary and secondary coupling elements and thus retains the load in attachment to the platform - and a second position, in which said aperture thereof is disengaged from said primary coupling element and said hook-like portion thereof is disengaged from said coupling seat, whereby said intermediate member is disengaged both from said primary coupling element and from said secondary coupling element, and the load is detached from the platform.

When the launch platform is an aircraft, the coupling device according to the invention comprises, in combination with a support member provided beneath the aircraft's fuselage and primary coupling elements fixed to said support and designed for engaging openings or recesses (hereinafter, "apertures") in secondary coupling members attached to the load, for retaining the load in carrying position, all as in prior art coupling devices: at least one secondary coupling element comprising a coupling seat provided in the load or in a seat member fixed to the load, said seat having an opening; and at least an intermediate coupling member (hereinafter, briefly, "intermediate member") having: a) an aperture adapted to be engaged by a primary coupling element, which is housed in a seat in said aircraft support member, and b) a hook-like portion adapted to engage said coupling seat; said intermediate member being displaceable from a first or active position - in which said aperture thereof is engaged by a primary coupling element and said hook-like portion thereof has been inserted through said coupling seat opening and engages said seat, whereby said intermediate member connects said primary and secondary coupling elements and thus retains the load in attachment to the aircraft - and a second or inactive position, in which said aperture thereof is disengaged from said primary coupling element and said hook-like portion thereof is disengaged from said coupling seat, whereby said intermediate member is disengaged both from said primary coupling element and from said secondary coupling element, and the load is detached from the aircraft.

Said hook-like portion of said intermediate member and said coupling seat of said secondary coupling element are correspondingly shaped to permit said hook-like portion to be displaced with respect to said seat and disengaged therefrom, to cause said intermediate member to pass from said active to said inactive position.

It is seen that when said intermediate member (hereinafter also, briefly, "tie"), which connects the load to the aircraft when in its active position, has assumed its inactive position, it is detached both from the aircraft and from the load. However, it need not be detached from the load at the same time that it is detached from the aircraft. Actually, it may be desirable, and it is included in the invention, to delay somewhat its detachment from the load until the aircraft is at a sufficient distance to assure that the aircraft does not impact with the tie.

Further, since the secondary coupling element, according to this invention, is essentially a seat, viz. a recess, it does not project from the load external surface and does not have the disturbing aerodynamic influence that a projecting element would have. In an embodiment of the invention, means are provided for closing the opening of said recess when the intermediate member becomes disengaged from it, and in this case the outer surface of the load becomes smooth, essentially as if there were no secondary coupling element.

The aperture of the intermediate member, adapted to be engaged by a primary coupling element, is located in the upper portion of said member which in the active position of said member projects from the surface of the load, while said hook-like portion (or briefly, hereinafter, "hook") constitutes the lower portion of the intermediate member and does not so project. The words "upper" and "lower", as used herein, are relative to an aircraft in level flight. Hereinafter, reference will be made to a bomb or missile as the load, though for illustration and not for limitation purposes. The coupling seat of the secondary coupling element, which will obviously be provided in the upper portion of the load, may be created in any convenient way, and may, for example, be formed in a body, hereinafter called "seat plug" or "plug", which in this case constitutes the secondary coupling element and is fixed to the load by any mechanical connection, or may be formed in the casing of the load itself, in a portion thereof which in this case may be considered as constituting the secondary coupling element. While only one coupling device, comprising a primary and a secondary coupling element and an intermediate member or tie, will be described, it will be understood that several coupling devices may be, and generally are, provided, so that the aircraft support member comprises a plurality of primary coupling elements, the bomb comprises as many secondary coupling elements as the size of the bomb may require, for engaging some or all of said primary coupling elements, and a number of intermediate members or ties is provided correspond ng to the number of secondary coupling elements.

The displacement of the intermediate member or tie, which causes it to pass from its active to its inactive position, is a rotation or a translation or a combination of both. If it is or comprises a rotation, this requires that a moment of rotation be applied to it. Said rotation of the tie is guided by the engagement of its hook portion with the coupling seat provided in the bomb or in a seat plug fixed thereto, and may be caused by the force applied by the resistance of the air to the portion of said tie projecting from the bomb surface. Optionally, it may be caused or assisted by activating means provided in said seat plug or in the casing of the bomb. Said activating means may be pressure-generating means, such as e.g. a compressed spring or a small pyrotechnic charge, provided in a space communicating with the hook seat, which will become initiated when the bomb is released and exert pressure on the end surface of the hook, to cause or to facilitate its operation and the detachment of the tie from the bomb.

Preferably, a disk-like stopper may be provided, which is housed in the hook seat adjacent or fixed to the end of the hook. Said stopper may be either drawn by said hook in its rotation, or transmit to said hook the pressure created by the pressure-generating means whereby to cause or assist its rotation, and will close the opening in the seat plug or in the bomb casing left by the tie when it becomes detached from the bomb. Means are provided to fix said disk-like stopper in the appropriate position to plug said opening and thereby avoid exposing to the air the recess constituted by the hook seat. The expression "disk-like", as used herein, does not necessarily designate a round body, the cross-section of the disk depending on that of the hook seat, but merely indicates a small plate-like body of any suitable contour.

The invention also comprises the combination of a load, specifically a bomb, and an intermediate coupling member, the load being provided, in its upper portion, with a seat for the lower portion of said member and said member being provided, in its upper portion, with a seat for a primary coupling element carried by a support member of an aircraft.

The invention also comprises the combination of a seat plug, adapted to be mounted in the upper portion of a load, specifically a bomb, having a seat formed therein, and an intermediate coupling member having a lower portion so shaped as to be adapted to engage said seat and become disengaged from it and being provided, in its upper portion, with a seat for a primary couphng element carried by a support member of an aircraft.

The invention also comprises a tie for connecting a load, particularly a bomb, to the underside of an aircraft fuselage, which has near one end a seat adapted to be engaged by a primary coupling element, carried by a support member of an aircraft, and at the opposite end a hook-like portion adapted to engage a seat in a secondary couphng element and to become disengaged from it by an essentially rotary displacement.

Brief Description of the Drawings In the drawings: - Fig. 1 is a schematic perspective view from above of a bomb having coupling elements fixed to its upper portion according to the prior art; - Fig. 2 is a schematic cross-section of a detachable coupling element and a seat plug engaged by it, according to an embodiment of the invention; the adjacent portion of the bomb casing being broken off, shown in the active condition of said coupling element; and - Fig. 3 schematically illustrates the same elements of Fig. 2, but in the inactive condition of the coupling element; - Fig. 4 is a cross-section of said coupling element and seat plug, taken on plane IV-IV of Fig. 2, looking in the direction of the arrow; and - Fig. 5 is a cross-section of Fig. 3, taken on plane V-V, looking in the direction of the arrow.

Detailed Description of Preferred Embodiments As seen in Fig. 1, a bomb 10 having couphng elements according to the prior art, is provided with a number of hook-like coupling elements fixed to it, such as loops 11, and it is apparent that these loops will have a significant effect on the aerodynamic behavior of the bomb after it has been released from the aircraft.

Figs. 2 to 5 show a coupling according to an embodiment of the invention, applied to a bomb carried by an aircraft - this being only an example, as has been said, and not limiting the invention. In this embodiment, the secondary coupling element comprises a seat plug 20 which is fixed to the upper surface of the bomb casing by any suitable means, for instance, by means of pins 21 (see Fig. 4). Seat plug 20 has therein a coupling seat 22, defined, in cross section, by two concentric arcs of circle 23 and 24 having their center at 25. The surface of the bomb casing is schematically shown, broken off, at 34. It is seen that the upper portion of the intermediate member or tie 27 projects, in the active position thereof shown in Fig. 2, to the outside of said surface 34 and is exposed to the resistance of the air. The upper portion of tie 27 has an aperture 28, which is engaged by a retaining hook 29, illustrated in broken lines, which retaining hook may be similar to those of the prior art and is housed in a support member fixed to the aircraft (not shown). Said retaining hook constitutes the primary coupling element. Tie 27 has a lower hook portion 30, shown in this embodiment as having a square transverse cross-section (see Fig. 4), but which may have any desired transverse cross-section. Hook portion 30 fits into the said seat 22 of plug 20, which has the same transverse cross-section of said hook, and is bound in longitudinal cross-section by arcs of circle(see Figs. 2 and 3), so that said hook portion can freely rotate in said seat. Said hook portion, in the active position of the tie illustrated in Fig. 2, is within the space defined by surface 34 of the bomb. In this preferred embodiment, a stopper 31 is also provided, but it may be omitted in other embodiments of the invention.

The bomb is released from the aircraft by operating, in the conventional way which requires no description, on the primary coupling elements, viz. on the retaining hooks mounted in a support member on the aircraft underside, by disengaging them from the corresponding apertures 28 of the intermediate members or ties. After the bomb has been released, the resistance of the air will exert a hydrodynamic force on the ties, as shown by the arrow A, since it is assumed that the aircraft is moving in the direction indicated by arrow B. The ties 27 will therefore become detached from the respective seat plugs 20 and from the bomb, since the hook portion of each tie has left the seat 22 of the corresponding plug 20, and at the moment of its detachment will assume approximately the position indicated in Fig. 3. If no means for creating forces are provided and the motion of the tie is due only to the resistance of the air, the stopper 31, which is preferably though not necessarily provided, will be attached to hook 30 and will therefore follow its rotation until it reaches the opening of the seat 22. As seen, the stopper is slightly larger than the end surface of the hook. Means are preferably provided for retaining stopper 31 when the hook 30 completely leaves seat 22. An example of such means is shown in Fig. 5. Two retaining spheres 36 are housed in cylindrical recesses 37 of seat plug 24 and are urged outwards by springs 38. As long as hook 30, or part of it, is in seat 22, it holds spheres 36 in recesses 37 against springs 38. When hook 30 leaves the seat plug, stopper 31 engages shoulders 39 of seat plug 24 and cannot follow the hook to the outside of the seat plug. Additionally, spheres 36 partly extend from recesses 37 under the action of springs 38 and thus stopper 31 is maintained flush to the outside surface 34 of the bomb casing. However, skilled persons could easily devise different mechanisms for achieving the same result, seat 22.

If, on the other hand, force-creating means, such as e.g. a pyrotechnic charge, which can be set off by an obvious wiring, or a spring, is provided at 35, the pressure that it creates will be exerted on stopper 31 and by it, on the hook. In this case, stopper 31 need not be attached to hook 30, and rather than being drawn by it, will assist, and might even cause, its motion, which will be the same as hereinbefore described.

Although in the embodiment illustrated the externally stored load is connected to and released from the underside of the aircraft fuselage, the invention can be applied to differently stored loads, for example loads connected to and released from the upper part of the fuselage or the wings of the aircraft.

While embodiments of the invention have been described by way of illustration, it will be apparent that the invention may be carried out with many modifications, variations and adaptations, without exceeding the scope of the claims. 5219/99 129948/3

Claims (17)

1. Coupling device for anchoring a releasable load to an aircraft, which comprises, in combination with a support member connected to the aircraft and primary coupling elements fixed to said support: a) at least one secondary coupling element comprising a coupling seat attached to the load and having an opening; and b) at least an intermediate coupling member having an aperture adapted to be engaged by said primary coupling element, and a hook adapted to engage said coupling seat, wherein said primary coupling elements is designed for engaging apertures in said intermediate coupling member, for retaining the load in carrying position, and said intermediate member being displaceable from an active position, in which said aperture thereof is engaged by said primary coupling element and said hook thereof engages said coupling seat, whereby said intermediate member connects said primary and secondary coupling elements, and an inactive position, in which said aperture thereof is disengaged from said primary coupling element and said hook thereof is disengaged from said coupling seat, whereby said intermediate member is disengaged both from said primary coupling element and from said secondary coupling element.

2. Coupling device according to claim 1, wherein the hook of the intermediate member and the coupling seat of the secondary coupling element are correspondingly shaped to permit said hook to be displaced with respect to said seat and disengaged therefrom, to cause said intermediate member to pass from said active to said inactive position. 5219/99 129948/2 -16-

3. Coupling device according to claim 1, further comprising stopper, means for closing the opening of the coupling seat when the intermediate member becomes disengaged from it.

4. Coupling device according to claim 1, wherein the secondary coupling element comprises a seat plug fixed to the load by a mechanical connection.

5. Coupling device according to claim 1, wherein the coupling element seat plug is formed in the casing of the load.

6. Coupling device according to claim 1, comprising a plurality of secondary coupling elements and a corresponding number of intermediate members.

7. Coupling device according to claim 1, wherein the displacement of the intermediate member, which causes it to pass from its active to its inactive position, is a rotation, guided by the engagement of its hook with the coupling seat.

8. Coupling device according to claim 1, wherein the rotation is caused by the force applied by the resistance of the air acting upon the portion of the intermediate member projecting from the load surface.

9. Coupling device according to claim 8, comprising pressure-generating means for causing or assisting the rotation of the hook. 5219/99 129948/5 -17-

10. Coupling device according to claim 1, wherein the pressure-generating means is chosen from the group consisting of pyrotechnic charges and springs, provided in a space communicating with the hook seat.

11. Coupling device according to claim 3, wherein the stopper means is a disk-like member housed in the hook seat adjacent to the end of the hook.

12. Coupling device according to claim 3, wherein the stopper means is a disk-like member fixed to the end of the hook.

13. Coupling device according to claim 1, which anchors a releasable load to the underside of an aircraft.

14. Coupling device according to claim 1, which anchors a releasable load to the upper part of an aircraft's fuselage.

15. Coupling device according to claim 1, which anchors a releasable load to an aircraft's wing.

16. Coupling device for anchoring a releasable load to a launch platform, which comprises, in combination with a support member provided in the launch platform and primary coupling elements fixed to said support: a) at least one secondary coupling element comprising a coupling seat attached to the load and having an opening; and b) at least an intermediate coupling member having an aperture adapted to be engaged by said primary coupling element, and a hook adapted to engage said coupling seat, 5219/99 129948/5 -18- wherein said primary coupling element is designed for engaging apertures in said intermediate coupling member for retaining the load in carrying position, and said intermediate member being displaceable from an active position, in which said aperture thereof is engaged by said primary coupling element, and said hook thereof engages said coupling seat, whereby said intermediate member connects said primary and secondary coupling elements, and an inactive position, in which said aperture thereof is disengaged from said primary coupling element and said hook thereof is disengaged from said coupling seat, whereby said intermediate member is disengaged both from said primary coupling element and from said secondary coupling element.

17. Coupling device according to claim 1, substantially as described and illustrated.