Patent Application
20170328692
The invention relates to a method and device for preventing vibrations or movements of missile wings exposed to air flow when these are in folded and stowed position. More specifically, the invention relates to a method for protecting a missile connected to a vessel carrying it, i.e. captive carriage, and to a cover serving as a protection and retention device for the missile wings as well as an air intake protection device for the missile.
Modern military vessels typically carry weapons such as unmanned aerial vehicles, missiles or cruise missiles that are jet powered and launched from the vessel at high speeds. Such missiles are typically equipped with wings that during captive carriage will be exposed to strong air flow resulting in forces and vibrations that necessitate a very strong mechanical design. For vessels like an aircraft at high speeds some missiles are typically carried in dedicated compartments in the fuselage of the aircraft.
To save space and cost some missiles can position their wings in a stowed position where the missile wings are folded alongside the missile such that a line going from the root of the wing to the tip will generally run in parallel to the missile body, either on top or on the side of the missile. Although such a construction will have fewer problems with vibrations it will also result in a more complicated mechanical construction.
Folding the wings down alongside the missile body such that a line from the root of the wing to the tip will point downwards can be an appropriate solution as it can lead to a relatively simple and strong mechanical construction in particular with regards to active flight. This solution will however suffer from strong forces induced by wind if the missile is to be carried as an external store. Wing covers used to protect wings during transport and storage must be removed before flight and have thus no effect on the vibration problem. Specially developed enforced wings on a missile for coping with strong air flow are expensive and will add to the total weight.
When designing a missile one will always try to minimize the volume needed during storage and “captive carry”. It is therefore important to consider the concept of stowing in an early phase of design.
The present invention presents a solution to these problems. The invention is described by a mechanical device and a method for protecting the wings of a missile.
One object of the present invention is to protect the wings such that these will not vibrate or move when stowed and exposed to strong air flow.
By placing the air intake ducts on the side of the missile, instead of the more commonly used underneath placement, allows to use available space in front of the air intake ducts to stow the wings. This is advantageous because this volume in most cases cannot be used for anything else.
Another object of the invention is to protect the air intake of the jet engine of a missile. For doing this, the inventive device for holding the wings of the missile also serves as a cover for the air intakes such that air flowing through them does not cause the rotating parts therein to spin freely, possibly resulting in excessive wear to bearings.
Upon launch of a missile it is vital that the inventive cover covering the air intake and holding the wings of the missile is removed in a predictable and safe way so that it does not collide with the missile.
A further object of the invention is to provide a predictable and safe removal of the cover after launch of the missile. The cover and its holding mechanism have been designed to assure a predictable trajectory away from the missile when removed.
Safe and predictable removal of the cover is achieved by first releasing the front end of the cover and secondly the rear part of the cover. In this way the cover will rotate around the rear part thereby assuring that the first part of the movement away from the missile is strictly governed by the rear holding mechanism.
The present invention is defined by a cover for protecting a missile with stowed wings and air intakes.
The cover comprises a front part, a bottom part, a rear part and suspension means. The front part covers a gap between the wings and the fuselage of the missile.
Further aspects of the cover are defined in the dependent claims.
The invention is also described by a method for protecting a missile with stowed wings and air intakes. The method is defined by:
Further aspects of the method are defined in the dependent claims.
The invention will now be described in more detail with reference to the accompanying drawings where:
Stowed wings on a missile are a usual configuration used for missiles carried by aircraft. These missiles may be carried in dedicated compartments in the fuselage, thus minimizing extra drag and protecting the missile, but this is not always a preferred configuration.
A missile can also be connected to a wing of an aircraft by means of pylons. For reducing wind forces acting on the wings of the missile the wings will typically be positioned in a stowed configuration where the wings are folded alongside the fuselage of the missile. Even though the wings of the missile are in a stowed position, a set of challenges such as unwanted aerodynamic effects will occur depending on the speed and movements of the aircraft.
The cover 10 can be made in any suitable material such as for instance a metal, metal alloy, plastic, carbon fiber or a combination of different materials. The cover 10 provides protection of a missile 15 with stowed wings 20 and air intakes 40, the cover 10 comprises a front part 25, a bottom part 30, a rear part 32 and suspension means, wherein said front part 25 of the cover 10 is streamlined and angled in a direction upwards relative to said bottom part 30, and where the front part 25 covers a gap between the wings 20 and the fuselage of the missile 15 for minimizing aerodynamic forces acting on it. The bottom part 30 of the cover 10 is made with a shape similar to the top side of an aircraft wing profile for generating aerodynamic forces acting downwards on the cover 10 relative to the missile 15.
In one embodiment of the invention the bottom part 30 of the cover 10 comprises suspension means for the cover to the missile 15.
In a preferred embodiment of the cover, the front part 25 is shaped such that the air intakes 40 of the missile 15 is engaged with the cover thereby providing full protection of the air intakes 40.
In order to provide a predictable and safe removal of the cover 10 after launch of the missile 15, the cover 10 and its suspension mechanism have been designed to assure a predictable trajectory away from the missile 15 when removed.
According to one embodiment of the invention, the suspension means of the cover 10 for connecting the cover 10 to a missile 15 comprises two hinges 45 located at the rear part 32 of the bottom part 30 of the cover 10, and a ball-lock mechanism 55 is located closer to the front part 25 of the bottom part 30 of the cover 10. Only one hinge 45 or more than two hinges 45 that are located at the rear end are also feasible. The hinges 45 and the ball-lock mechanism 55 are connected to the missile 15 by corresponding engaging means mounted on the missile 15.
At least one of the suspension means comprises a release mechanism 50. In one embodiment this can be a forcing mechanism connected to the ball-lock mechanism 55 such that when the mechanism is released the front part of the cover 10 will be released and swing downwards. The ball-lock mechanism may be replaced by a magnetic or electro-magnetic mechanism.
Safe and predictable removal of the cover 10 is achieved by first releasing the front part 25 of the cover 10 and secondly the rear part 32 of the cover 10. In this way the cover 10 will rotate around the rear part 32 thereby assuring that the first part of the movement away from the missile 15 is strictly governed by the rear suspension mechanism.
In one embodiment of the invention the rear suspension mechanism is at least one hinge 45 that is designed with an open slot for releasing the cover 10 when it rotates away from the missile 15.
In one embodiment of the invention the cover 10 further comprises retention means 35 for holding the wings 20 in a folded and stowed position alongside the missile 15. This will further contribute to the protection of the wings 20 of the missile.
Different types of retention means 35 are possible. In one embodiment the retention means 35 is a slot comprised in the cover 10.
In one embodiment, the slot can for instance be covered by a soft material enclosing and firmly holding the tip of the wing 20.
In another embodiment the slot comprises a magnetic material for holding a magnetized tip of a wing 20 firmly in the channel or slot.
In yet another embodiment the retention means 35 can be other positioning or holding means other than a channel or slot. Examples of other means are one or more gripping arms or pins for keeping the wings 20 in a stable position.
The hinge mechanism can be made with an open slot such that when the cover 10 has rotated for instance 90 degree from its initial resting position, which is the position when it is mounted to the missile 15, it will drop out of the hinge 45 and quickly move away from the missile 15. This will ensure a secure removal of the cover 10 without coming in contact with the missile 15. In order to provide a more controlled movement out of the hinges 45, springs can be mounted in the hinges 45 for pushing the suspension means out of the hinge 45 when the cover 10 has rotated a certain degree from its initial resting position.
The invention is further defined by a method for protecting a missile 15 with stowed wings 20 and air intakes 40. The method comprises a first step of providing a cover 10 comprising a front part 25, a bottom part 30, a rear part 32 and suspension means, wherein said front part 25 is spoiler shaped and angled upwards relative to said bottom part 30, and where the front part 25 is shaped for covering a gap between the wings 20 and the fuselage of the missile 15. The next step is folding the wings 20 of the missile 15 in a stowed configuration alongside the missile 15 and in front of the air intakes 40. The last step is mounting the cover 10 on the missile 15 by means of the suspension means such that the front part 25 of the cover 10 is covering a gap between the wings 20 and the fuselage of the missile 15 thereby minimizing aerodynamic forces acting on the wings.
In one embodiment the method further comprises the step of fitting the wings 20 of the missile 15 into retention means 35 comprised in the cover 10 for holding the wings 20 in a stowed position alongside the missile 15.
In one embodiment the method further comprises the step of mounting the cover 10 over the air intake 40 on the missile making the cover 10 engage with the air intakes 40.
In one embodiment the method further comprises the step of removing the cover 10 after launching the missile 15, thus releasing the wings 20 and exposing the air intakes 40.
A safe and predictable removal of the cover 10 is achieved by first releasing the front part 25 of the cover 10, and then the rear part 32 of the cover 10. In this way the cover 10 will rotate around the rear part thereby assuring that the first part of the movement away from the missile 15 is strictly governed by the rear holding mechanism.
In one example, the front part 25 of the cover 10 is released first by a release mechanism 50. This can for instance be a forcing mechanism connected to a ball-lock mechanism 55 such that when the ball-lock releases the front part of the cover 10 will be released and swing downwards. After this the rear part 32 of the cover 10 will rotate in a hinges in the rear part 32, where the hinges have an open slot. This will assure that the first phase of the movement is away from the missile and strictly governed by the suspension means in the rear part 32 of the cover 10.
The present invention presents a space efficient way of protecting the wings 20 of a missile 15 such that vibration and movement will be minimized when these are stowed and exposed to strong air flow. The invention will further protect the air intake 40 of the jet engine of a missile 15.
The inventive cover 10 providing said protection is made such that it will be quickly removed in a safe way away from the missile 15.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2014/074020 | 11/7/2014 | WO | 00 |
