The invention generally pertains to aircraft structural systems, and more particularly to a truss reinforced radome crown structure shock absorbing and recoiling system that is utilized for any type of SAT-COM connectivity device to allow for pressurized expansion and contraction, and to protect an aircraft from damage resulting from a bird strike incident or rapid decompression event if the fuselage skin were to tear directly under a radome crown structure.
In the modem world, there are many methods of transportation. One of the most widely used methods, for trips of all distances and durations, is by aircraft, which are utilized for personal, commercial, military/government, and for other purposes. One of the most important capabilities of modern aircraft is the inclusion of an advanced communication system. A major component on many communication systems is a radome/antenna that functions in combination with communication satellite(s), air to air or air to ground data links.
Typically, a radome/antenna(s) or other SAT-COM hardware is attached either within an aircraft's nose cone, or onto an outer surface of the aircraft. When radome/antennas are mounted to an outer surface, a platform or adapter plate is typically required to support the fairing and radome/antenna assembly. An improved method of supporting the fairing utilizes a truss design.
Typically, an aircraft's fuselage will expand or contract as the pressure varies. For example, an aircraft fuselage can grow by up to 0.30 inches. When this occurs, items such as radomes/antennas that are usually affixed onto the fuselage can be damaged if not allowed to flex as the fuselage expands.
The solution to this problem would be to provide a push/pull shock absorber or fuselage expansion link that would allow an antenna/radome or other communication hardware to absorb the forces of pressurization an aircraft experiences. Optimally, a strut with shock absorbing and recoiling capability would be utilized. A strut or fuselage expansion link could be placed at each attachment point of a radome/antenna mounting plate and would allow the plate to absorb the expansion and contraction of the fuselage while returning the fuselage to its original position after landing once cabin pressure equals neutral barometric pressure on the ground.
To further the utility, a complete system could be utilized to protect an aircraft from normal fuselage expansion and contraction, a rapid decompression event or a bird strike incident depending on whether the struts are mounted horizontally for a bird strike incident or vertically as for a rapid decompression event. Without this flexible protection an extreme event could cause catastrophic damage and/or loss of life. The system could utilize a strut that also includes sliding actuators which allow the strut to move horizontally in pull, pull/push or push directions to absorb a bird strike incident or if attached between lugs and a radome fairing in a vertical mariner the strut would allow normal fuselage expansion or protect a radome crown structure from a rapid decompression event.
All of the above elements of the system would be beneficial and would be a significant improvement to current aircraft technology. The system would protect an airframe from a catastrophic incident such as a bird strike or rapid decompression if the fuselage were to tear directly under a radome crown structure. A shock absorbing and recoiling crown structure would be light weight, decrease costs and increase safety.
A search of the prior art did not disclose any literature or patents that read directly on the claims of the instant invention. However, the following U.S. patents are considered related:
The U.S. Pat. No. 8,839,919 patent discloses a shock absorber that is attached coaxially with a reciprocating rod driven by a reciprocating unit for absorbing an impact force. A hollow rod is mounted within an outer cylindrical body, with an accommodating space is formed there between. A spring force toward one end portion side of the hollow rod is applied to the outer cylindrical body by a compression coil spring. When the impact force is applied to the hollow rod, a liquid flows from one chamber to another chamber, whereby a resistance force is applied to the hollow rod.
The U.S. Pat. No. 9,249,727 patent discloses a deflector to deflect birds and debris from an air intake duct of an aircraft jet engine. The deflector includes a plurality of elongated members disposed on the duct in spaced relation to each other with each member having two end segments and a central segment disposed between the two end segments, and a plurality of guiding members, each mounted for movement along the perimeter of the duct and coupled to one end segment of an elongated member. The elongated member is movable by a respective pair of guiding members between a retracted position and a deployed position. When in the deployed position, the central segments are situated to impede the ingress of debris into the duct.
The 2017/0016502 publication discloses a magnetic shock absorber having a first body slidably coupled to a second body via a first bearing arranged to move in sliding engagement with a first counter-face portion. A first array of magnets associated with the first body is arranged to magnetically interact with a second array of magnets associated with the second body to absorb compression or extension loads applied to the shock absorber.
For background purposes and indicative of the art to which the invention relates, reference may be made to the following patent:
A truss reinforced radome crown structure shock absorbing and recoiling system that allows/compensates for fuselage expansion during aircraft cabin pressurization and to absorb the force of a bird strike or survive a catastrophic event cause by rapid decompression.
There are multiple design configurations of the system: the first design configuration is for mounting an antenna adapter plate, or other satellite communication (SAT-COM) crown structure and hardware to an aircraft fuselage, allowing for pressurized expansion and contraction of the fuselage. Second and third design configurations provide recoiling shock absorbing protection from both a bird strike incident or rapid decompression event.
In all of the design configurations the system comprises an actuating recoiling strut with a housing, a male cap, an actuating rod and a compression spring. In lieu of a spring, other resilient members can be utilized, and the functionality of the system can be accomplished by use of other means or materials such as hydraulic or pneumatic devices, and rubber or elastic materials. Also, the system can be attached by means of cables, rods or tubes which may include spherical bearings or heim joints.
The housing is preferably made of a metal such as aluminum, but can also be made of other materials including carbon fiber or composite materials, and the size of the housing can vary depending on the requirements of use.
The first design configuration is primarily used with an aircraft's adapter plate for antenna mounting and allows for fuselage expansion during pressurization. In the second design configuration the actuating recoiling strut can be used with any crown structure system to allow a crown structure to recoil when struck by a bird or in reaction to a rapid decompression event. In the third design configuration, the actuating recoiling strut is attached to a slide mechanism that is mounted at either an actuating base plate and/or attachment lugs. Alternately, when the system is utilized with an adapter plate that supports both antennas and/or an aircraft's fairing skirt and radome, the entire adapter plate functions as a single large unitary shock absorber.
In view of the above disclosure the primary object of the invention is to provide a truss reinforced radome crown structure shock absorbing and recoiling system that provides an actuating recoiling strut that is used with or without an adapter plate to accommodate aircraft fuselage expansion during cabin pressurization and to protect against a bird strike incident or rapid decompression event.
In addition to the primary object, it is also an object of the invention to provide a truss reinforced radome crown structure shock absorbing and recoiling system that:
These and other objects and advantages of the present invention will become apparent from the subsequent detailed description of the preferred embodiment and the appended claims taken in conjunction with the accompanying drawings.
The best mode for carrying out the invention is presented in terms that disclose a preferred embodiment with multiple functional design configurations of a truss reinforced radome crown structure shock absorbing and recoiling system. The first functional design configuration of the system is for mounting an antenna adapter plate, or other SAT-COM crown structure and hardware to an aircraft fuselage, allowing for pressurized expansion and contraction of the fuselage. The second and third functional designs provide recoiling shock absorbing protection from both a bird strike incident or rapid decompression event.
The system 10, as shown in
Located within the housing 14 is the actuating rod 56, as shown in
The spring 68 can be as long or short as required. Located adjacent the second end 64 of the actuating rod 56, is at least one internal spring adjustment space 72. As shown in
The opening 38 and the internal threaded cavity 40 on the male cap's first end are dimensioned to accept the second end 84 and threaded section 86 of the attachment fitting 74. The fitting is attached to the housing 14 by screwing the fitting's second end 84 and threaded section 86 into the internal threaded cavity 40. The distance the fitting 74 extends outward from the housing 14 can be adjusted by the amount the fitting 74 is screwed into or out from the cavity. The first end 76 of the fitting also has a spherical bearing 80 within the opening 78.
The first ends 58,76 of the actuating rod 56 and the attachment fitting 74 both function as attachment members for securing the actuating recoiling strut 12, as shown in
The primary benefit of using the first design of the system 10 is that the actuating recoiling strut(s) 12 allows antenna adapter mounting flexibility to allow for fuselage expansion during pressurization. Under pressurization all aircraft fuselages grow by the amount of pressurization. An A320 and B737 airplane each have a fuselage diameter of approximately 152±4 inches. When the cabin is pressurized during a flight the diameter of the fuselage can enlarge by 0.3 inches resulting in fuselage expansion of 0.15 inches outward in every direction.
The actuating strut allows for this enlargement/expansion when joined to an aircraft's fixed fuselage fitting and a fixed antenna or SAT-COM communication system's antenna adapter plate, ARINC 791 attachments, truss or other designs of attachment systems. The strut(s) can be used with one side of an adapter plate hard mounted by attachment and the lugs actuating recoiling struts mounted to the opposite side of the attachment lugs. The actuating strut(s) can be mounted utilizing as many horizontal, vertical or angled shock absorbing struts required for a particular truss structure to support the size and weight of an adaptor plate, fairing, radome and/or antennas, as well as any form of SAT-COM connectivity device.
In the second functional design configuration, the truss reinforced radome crown structure utilizes actuating recoiling struts that can be used with any crown structure system to allow a crown structure to recoil when struck by a bird or to recoil in reaction to a rapid decompression event. The second design configuration, as shown in
By mounting the adapter plate attachment lugs to slide mechanisms attached to the base of the adapter plate with an actuating recoiling strut mounted behind each lug attachment to the aft or forward of each attachment, as shown in
The second design of the radome crown structure is to be securely fixed and attached to an aircraft's airframe or fuselage to allow either the crown structure or components of the crown structure to recoil upon impact. This system provides shock protection to an airframe, radome and mounting attachments from a rapid decompression event, bird strike or any potentially damaging objects that could impact the crown structure at speeds required for flight. The system can be designed to be used in conjunction with any recoiling flexible means or materials, hydraulic shocks, gas or spring-loaded shocks or any flexible device such as rubber, flexible cords or spring-loaded tension adjustable actuating struts designed to absorb the force of the strike or incident. The recoiling system can be designed into any single attachment or multiple attachments between the affixed fittings supporting the fairing and radome, adapter plate or truss system, as shown in
The benefits/attributes of the second design are: Protects airframe, radome crown structure, tail, rear horizontal stabilizers and rear control surfaces from damage, is light weight, decreases costs and increases safety. An alternate embodiment in the second design, of the system would be to mount the shock absorbing recoiling struts to only the forward area of the truss crown structure. The forward crown structure attachments are replaced with actuating struts as in one version of the system as designed is only 4.4-inches tall and has a very low incident for bird strike impact. By replacing the upper forward facing rod link attachments with actuating recoiling struts, it allows for added flexibility of the aircraft's fairing and radome to absorb the forward shock of the bird strike or other impact.
In the third functional design configuration of the system 10, as shown in
In summary, the system 10 provides a solution to allow an actuating recoiling strut that is used with or without a fixed adapter plate to accommodate fuselage expansion during cabin pressurization and to protect against a bird strike incident or rapid decompression event if a fuselage tear occurs under the radome crown structure.
The first design allows antenna adapter mounting flexibility to allow for fuselage expansion during aircraft cabin pressurization. All aircraft fuselages expand when pressurized. A B-737 airplane at 74.080 and an A-320 airplane at 77.750 radiuses have a fuselage diameter of approximately 152-inches. When the cabin is pressurized to 9000 feet or the standard pressurization of a normal commercial flight, the diameter of the fuselage grows by 0.30-inches. The fuselage actually expands 0.15-inches in all circumferential directions. The actuating strut maintains the fixed antenna adapter in place by slightly collapsing while the fuselage expands and while the adapter plate remains in a fixed position. The system allows the attachment hardware to be maintained in a fixed and stationary position without the possibility of the hardware shearing or deforming as the fuselage expands under pressurization. This fixed/floating attachment system works for any connectivity device whether air to ground, air to air or for SAT-COM or newly developing laser connectivity systems. The actuating strut recoiling system will work with any externally mounted equipment requiring the attachment plate to be maintained in a fixed position while allowing the fuselage to expand while being pressurized. The system can be used with one side fixed or hard mounted and as the fuselage expands, the side with the actuating struts can become a flexible link. In many cases, the center of the antenna adapter is fixed and each side is allowed to float by using the actuating struts on adjacent sides.
The second design of the system 10, as shown in
As previously disclosed, the third design of the system is by using actuating struts connected to a slide mechanism, as shown in
The system utilizes actuating struts as an element of vertical slide mechanisms 112 that are mounted at either adapter plate attachment lugs or between fuselage lugs, as shown in
It should be noted that all designs of the system can use any type of flexible resilient material that is capable of absorbing and reacting to impact. After an impact, the material will allow a radome crown structure, or other structure to return to the original position prior to the impact.
Also, the system 10 has been designed and implemented both using and adapted for current technology. The system is intended to be adaptable to changes and improvements in technology while maintaining the functionality and utility disclosed herein.
While the invention has been described in detail and pictorially shown in the accompanying drawings it is not to be limited to such details, since many changes and modification may be made to the invention without departing from the spirit and the scope thereof.
Number | Date | Country | |
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62318489 | Apr 2016 | US |