Aircraft with integrated jettison mechanism

An aircraft (1) with jettison mechanism, particularly a helicopter, comprising an airframe (2), at least one door (5) movably mounted to the airframe (2), at least one door lock mechanism (9) at an interface of said at least one door (5) with the airframe (2) to releasable mount the at least one door (5) relative to the airframe (2) and actuation means (11) for the at least one door lock mechanism (9). An emergency jettison button (20, 38) is integrated into handles (11, 12) of said actuation means.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to European patent application No. EP 13400004.1, filed on Mar. 18, 2013, the content of which is incorporated in its entirety by reference herein.

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The invention relates to an aircraft with a jettison mechanism.

(2) Description of Related Art

After an accident it is important for all occupants of an aircraft to be able to leave the aircraft quickly. Due to deformation of the airframe as a consequence of the accident the doors may be jammed and it may not be possible to open the doors in a normal way to exit the occupants.

A large exit from the aircraft can be achieved by jettisoning the door from the aircraft by severing all connections of the door to the airframe. A large exit is particularly advantageous if elements, such as backrests of seats project into windows to be used as emergency exits, thus reducing the available cross section for egress by such windows emergency exits.

Door lock mechanisms, e.g. a door lock mechanism of a door of an aircraft, are so arranged, that when the door arm of said door lock mechanism is disconnected, the door will not separate as long as the door lock mechanism is closed. If the door is jettisoned with the door lock mechanism closed the door can be blocked against the fuselage. Therefore the design has to ensure that the jettisoning and unlocking of the door has to be done at the same time.

The document U.S. Pat. No. 3,131,892 describes a door latch assembly for aircraft and helicopters. A closure member for an access opening is secured in completely closed and open positions, but also in a variety of intermediate position. The closure member may be completely removed or jettisoned. When in a generally horizontal position, a cam follower unit makes the door being constrained against reciprocate opening/closing movement. Into another position it effects relative movement between the various sections of a carrier assembly and the unit in the opposite directions, thereby releasing the carrier assembly from frictional engagement with walls of a channel. This permits the door to be reciprocated along the fuselage between. When it is desired to remove the door for jettisoning, a first handle is displaced beyond a limit defined by an abutment element, by rotating a stop lever, distinct and distant from the handle, to remove the abutment element from the path of the handle. Cam followers are completely withdrawn from respective cam slots so that the door is free to fall, since the only forces active on the door which tend to prevent such fall are imparted thereto through an interconnection of the assembly and unit now disengaged.

The document US 2012/085865 describes a door assembly for a helicopter. The door assembly has a post; a door fitted to the post by a first and a second hinge, so as to rotate about a hinge axis to open and close a door opening. An emergency release device has a release handle, and a stem which extends through the post along a release axis substantially perpendicular to the hinge axis, rotates axially, in response to operation of the release handle, from a first to a second angular position to detach the door from the post, and is fixed at one axial end to the first hinge; the release handle being connected to the stem to rotate together with the stem about its release axis.

The document U.S. Pat. No. 6,341,748 discloses an emergency exit system for use primarily in a helicopter or other aircraft. Said emergency exit system includes a panel closing an opening in the fuselage of the aircraft, a plurality of latches for releasably securing the panel in the opening; a release mechanism including slides on each side of the opening for retracting the latches to release the panel; a drive for operating the slides, a drive latch for releasably locking the drive in a cocked condition; and a plurality of principal grab bars strategically located in notches adjacent to the opening and connected to the drive by cables, whereby actuation of any one of the grab bars causes simultaneous release of all of the latches so that the panel can be jettisoned.

The document U.S. Pat. No. 6,427,383 discloses an emergency exit system for use on a helicopter or other aircraft. Said emergency exit system includes a frame defining an opening for receiving a panel to close the opening; a plurality of latches for releasably securing the panel in the opening; a plurality of release mechanisms; a cable extending around at least a major portion of the frame for releasing the panel; and a plurality of actuators strategically located around the opening and connected to the cable, whereby actuation of any one of the actuators causes simultaneous release of all of the latches so that the panel can be jettisoned.

The document EP 0935556 discloses an emergency egress system for facilitating emergency egress of passengers/crewmembers from an aircraft. Said egress system includes an egress panel, a panel frame disposed about the egress panel and a weather strip defining back-to-back channels for accepting the peripheral edges of the egress panel and the panel frame. Furthermore, the emergency egress system includes a plurality of retention devices disposed about the periphery of the egress panel for laterally retaining the egress panel with respect to the panel frame in a normal operating mode, a cam means operative to forcibly urge a portion of the weather strip out of engagement with one of the peripheral edges and an actuation means operative to sequentially disengage at least one of the retention devices and actuate the cam means in an emergency operating mode. Following actuation, a passenger/crewmember may detach the egress panel from the panel frame.

The U.S. Pat. No. 3,851,845 relates to an aperture closure device incorporating a quick release mechanism adapted for incorporation in an aircraft door to effect jettisoning of the door in an emergency. The device includes a plurality of separable hinges operated by a single lever from within the aircraft which can further incorporate means for simultaneously releasing the normal door closing mechanism, thereby effecting complete release of the door by operation of the single lever incorporating a quick release mechanism.

BRIEF SUMMARY OF THE INVENTION

One of the causes of confusion after civilian and military helicopter accidents is that occupants have difficulty locating the jettison mechanism and, if they do find it, they experience difficulty operating it in the right sequence.

A technical problem of the invention is to provide an aircraft with a jettison mechanism for jettisoning of a door with an existing door lock mechanism. A further technical problem of the invention is to simplify door operation and to provide a jettison able aircraft door without the disadvantages of the prior art.

A solution is provided with an aircraft with a jettison mechanism with the features of claim1of the invention. Embodiments of the invention are presented in the dependent claims.

An aircraft, particularly a helicopter, with jettison mechanism, comprises an airframe and at least one door connected with connection means, e.g. at least one guide arm and/or hinges, to said airframe. The connection means movably mount said at least one door to compatible supports, e.g., guide rails, integral with the airframe. At least one door lock mechanism is provided at an interface of said at least one door with the airframe to releasable hold the at least one door relative to the airframe.

Further provided are actuation means, preferably a handle, to open or close the at least one door lock mechanism, to subsequently allow movement of said at least one door guided relative to the airframe by the connection means. Further provided is an emergency button integrated into the actuation means. The actuation means are connected to the at least one door lock mechanism and are optionally connected to the connection means. At least parts of the connection means are operable to allow separation of said at least one door from the compatible supports.

Upon actuation of said emergency button the actuation means are connected mechanically to the jettison mechanism. Subsequently separation of the connection means from the supports of the at least one door to sever said at least one door from the airframe while releasing at the same time the at least one door lock mechanism is effected upon actuation of the actuation means with the mechanically locked emergency button of the jettison mechanism. The aircraft arms the jettison mechanism for its associated at least one door by means of said emergency button integrated with the actuation means and optionally linked to the connection means.

The actuation means operate the door lock mechanism and with the emergency button pushed as well the connection means to sever the at least one door entirely from the airframe at less time and without causing confusion for any person attempting to escape through the at least one door from the inside of the airframe. To jettison at least one closed door of the aircraft, two actions with said integrated emergency button and the actuation means are needed: first pressing said emergency button integrated into the actuation means and then jettisoning the at least one door by actuating the actuation means, whereas according to the state of the art the disengagement of the locking devices for a closed door is followed by a separate disconnection of the other connecting elements through a second handle or handles. The aircraft with a jettison mechanism with one separate handle satisfies the safety requirements with at least two different actions necessary to sever the door. The integrated emergency button and the actuation means of the inventive aircraft are mounted on the door for an integrated construction of the mechanical connections particularly suitable for operating a sliding door.

The elements for the jettisoning are all located in one actuation means/handle, thereby limiting the time needed to find them in an emergency.

There is no need to change the grip on handles during the jettison procedure.

Intuitively the occupants will try to open the door with the handles and the inventive arrangement is suitable to draw the occupants' attention to the integrated emergency button for jettison.

The normal door opening mechanism is used to disconnect several of the elements connecting door and airframe.

No cluttering of the door with several handles or other similar elements.

To jettison the door the passenger has to use only one handle simplifying and accelerating the jettison procedure.

Confusion is reduced by using one clearly identifiable actuation device which actuates all necessary mechanisms.

In an embodiment of the invention the integrated emergency button is behind a quick remove cover to prevent accidental actuation of the integrated emergency button.

In an embodiment of the invention the integrated emergency button and the actuation means are mounted internally and externally on the door for operation of the door from inside and outside.

In an embodiment of the invention the mechanism from said actuation means to the door locks and to the connection means comprise Bowden cable and/or Push-Pull-Rods.

DETAILED DESCRIPTION OF THE INVENTION

According toFIG. 1a helicopter1as an aircraft is provided with an airframe2. An upper guide rail3and a lower guide rail4are mounted parallel to each other and longitudinally along an outside of the airframe2. A movably sliding door5with a window6is held with upper hinges7of connection means in the upper guide rail3and with lower hinges8in the lower guide rail4. The door5ofFIG. 1is longitudinally movably sliding. The door5is lockable to the airframe2by a door lock mechanism9at an interface of said at least one door5with the airframe2to releasable lock the at least one door5to the airframe2.

The actuation means comprise handles11/12. OnFIG. 1, the door5has a frontal handle11that is outside the door5. OnFIG. 2, the door5has a frontal handle11and a handle12that are both inside the door5. When opening the door5by one handle11/12, for actuation of the door lock mechanism9, the door5is moved in curved guide rails21relative to the airframe to allow exit from or access to the inside of the airframe2of the helicopter1. OnFIG. 1, the outside handle11has an aerodynamic cover41, which is external.

According toFIG. 2corresponding features are referred to with the references ofFIG. 1. Two handles11,12of the actuation means are provided separately inside on the door5at a lower frame13below the window6. The handles11,12are respectively mounted on shafts15, rotatable held at the lower frame13, said shafts15connecting the handles11,12to the actuation means for the door lock mechanism9of the door5. An unlocking cam and shaft system/push-pull rod10mechanically connects each of the handles11,12via the rotatable shafts15of the actuation means to the door lock mechanism9of the door5. With the handles11,12aligned to the frame13of the window, the door lock mechanism9is closed. If one or all of the handles11,12are pulled upwards for rotation around the shafts15, the door lock mechanism9is opened.

Each of the handles11,12for the door lock mechanism9are provided with a respective emergency buttons20,38for activation of a jettison mechanism, i.e., for separation of at least one of the hinges7from the upper guide rail3in order to sever the door5from the airframe2. The lower hinge8falls out of the lower guide rail4due to gravity once the upper hinges7are free from the upper guide rail3.

A severing Bowden cable16mechanically connects the frontal handle11to a mechanical unit24and a further severing Bowden cable23mechanically connects the handle12to the mechanical unit24. From the mechanical unit24a Bowden cable25of the connection means leads to the upper hinge7of the jettison mechanism, said Bowden cable25transmitting the inputs from either the severing Bowden cable16and/or the further severing Bowden cable23to the hinge7.

According toFIGS. 3-5corresponding features are referred to with the references ofFIG. 1, 2. The handle12is provided with a handle casing17mounted on the shaft15rotatable held in the lower frame13. A lever18is mounted on a hollow shaft26, said hollow shaft26being mounted coaxial to the rotation axis of the shaft15with one end in the handle casing17. The further severing Bowden cable23is actuated by the lever18mounted on the hollow shaft26.

Coaxially inside the hollow shaft26is provided a central shaft32for rotation with the handle casing17. Said central shaft32is driven with the shaft15and is projecting beyond the hollow shaft26. The unlocking push-pull rod10is connected to the central shaft32. Upon pulling up the handle12for rotation around the shaft15, the central shaft32is turned to pull the unlocking push-pull rod10and subsequently the door opening mechanism9is actuated.

The hollow shaft26is provided with a notch33at its periphery inside the handle casing17, said notch33pointing towards the emergency button20. The hollow shaft26is rotatable relative to the shaft15and the handle casing17.

The emergency button20is provided at an open upper side of the door handle casing17distal to the shaft15. The upper side is directed towards the upper frame14. Inside the handle casing17are a block27, a spring28, a pin29and a further spring30all lined up coaxially towards the shaft15. The handle casing17is provided with a lateral cover34for insertion of the emergency button20, the block27, the spring28, the pin29and the further spring30.

The emergency button20is fixed with a pintle35through the lateral cover34to the door handle casing17distal to the shaft15. The pin29is provided with a tip36extending through the further spring30towards the notch33at the periphery of hollow shaft26. The tip36is adapted for entry into the notch33. The further spring30is supported by an abutment37inside the door handle casing17, said further spring30urging the pin29away from the shaft15towards the emergency button20.

The emergency button20is covered with a protective cap forming a quick removal cover31, set on the handle casing17. The protective cap has to be removed to gain access for actuation of the emergency button20.

Method to operate the jettison via handle12is described.

If the emergency button20is pushed into the door handle casing17, the emergency button20slides and is locked inside the door handle casing17towards the shaft15. The emergency button20compresses spring28via block27and further compresses spring30by pushing pin29towards the shaft15and into the notch33at the periphery of the hollow shaft26. With the pin29inserted into the notch33, the shaft15is locked to the hollow shaft26. If the handle12is pulled up and rotated around the shaft15with the pin29inserted into the notch33, the hollow shaft26is rotated with the lever18. The lever18further moves the severing Bowden cable23to mechanically transmit the rotation of the handle12to the mechanical unit24and via Bowden cable25of the connection means to the hinge7of the jettison mechanism.

The further spring30prevents unintentional engagement of the pin29when the emergency button20is not pushed.

According toFIGS. 6-8corresponding features are referred to with the references ofFIGS. 1-5. A frontal handle11is provided with the handle casing17mounted on the shaft15rotatable held in the lower frame13. The lever18is mounted on the hollow shaft26. The hollow shaft26is mounted coaxial to the rotation axis of the shaft15with one end in the handle casing17. A severing Bowden cable16is actuated by the lever18mounted on the hollow shaft26.

Coaxially inside the hollow shaft26is provided the central shaft32for rotation with the handle casing17. Said central shaft32is driven with the shaft15and is projecting beyond the hollow shaft26. The unlocking push-pull rod10is connected via an unlocking lever19to the central shaft32. Upon pulling up the frontal handle11for rotation around the shaft15, the central shaft32is turned to pull the unlocking push-pull rod10and subsequently the door opening mechanism9is actuated.

The hollow shaft26is provided with the notch33at its periphery inside the handle casing17, said notch33pointing towards a frontal emergency button38. The hollow shaft26is rotatable relative to the shaft15and the handle casing17.

The frontal emergency button38is mounted into the door handle casing17through a circular opening39at a front side of the door handle casing17distal to the shaft15. Inside the handle casing17are the pin29and the further spring30aligned coaxially towards the shaft15. The handle casing17is provided with a lateral cover34for insertion of the frontal emergency button38, the pin29and the further spring30.

The frontal emergency button38is withheld by a cube40in the door handle casing17distal to the shaft15. The pin29is provided with the tip36extending through the further spring30towards the notch33at the periphery of hollow shaft26. The tip36is adapted for entry into the notch33. The further spring30is supported by the abutment37inside the door handle casing17, said further spring30urging the pin29away from the shaft15towards the frontal emergency button38.

The frontal emergency button38is covered with a protective cap forming a quick removal cover31, set on the handle casing17. The protective cap has to be removed to gain access for actuation of the frontal emergency button38.

Method to operate the jettison via frontal handle11

If the frontal emergency button38is pushed the frontal emergency button38is slid inside the door handle casing17towards the shaft15compressing further spring30by pushing pin29towards the shaft15and into the notch33at the periphery of hollow shaft26. With the pin29inserted into the notch33the shaft15is locked to the hollow shaft26. If the frontal handle11is pulled up and rotated around the shaft15with the pin29inserted into the notch33, the hollow shaft26is rotated with the lever18and severing Bowden cable16, to mechanically transmit the rotation of the frontal handle11to the mechanical unit24and via Bowden cable25of the connection means to the hinge7of the jettison mechanism.

The further spring30prevents unintentional engagement of the pin29when the frontal emergency button38is not pushed.

LIST OF REFERENCES