Structural part for lightning strike protection

Abstract

A structural part for lightning strike protection, preferably of an aircraft includes a first structure element, wherein the first structure element includes a conducting material and is adapted to conduct electric currents into a grounded conducting airframe structure, and a second structure element, wherein the second structure element includes an outer layer with a first surface, wherein the outer layer includes a composite, preferably carbon-fibre reinforced plastic, CFRP or glass-fibre reinforced plastic GFRP. The structural part further includes a first elongated, preferably wedge-shaped, electrical conductor, with a first end and a second end, wherein the first end of the first elongated electrical conductor is connected to the first structure element and extends through the second structure element to the first surface, so that the second end of the first elongated electrical conductor serves as a lightning receptor without impairing the radar cross section of the aircraft.

Claims

1. An aircraft comprising a structural part for lightning strike protection of the aircraft, wherein the structural part comprises: a first structure element, wherein the first structure element comprises a conducting material and is adapted to conduct electric currents into a grounded conducting airframe structure, a second structure element, wherein the second structure element comprises an outer layer with a first surface, wherein the outer layer comprises a composite; comprising carbon-fibre reinforced plastic, (CFRP) or glass-fibre reinforced plastic (GFRP), a first elongated, electrical conductor, with a first end and a second end, wherein the first end of the first elongated electrical conductor is connected to the first structure element and extends through the second structure element to the first surface, so that the second end of the first elongated electrical conductor serves as a lightning receptor without impairing the radar cross section of the aircraft, wherein the first elongated electrical conductor is arranged in the second structure element in a first orientation, and wherein the first orientation is adapted to be aligned parallel to the rolling axis of the aircraft.

2. The structural craft, according to claim 1, the structural part further comprising a second elongated, electrical conductor with a first end and a second end, wherein the first end of the second elongated electrical conductor is connected to the first structure element and extends through the second structure element to the first surface, so that the second end of the second elongated electrical conductor serves as a lightning receptor without impairing the radar cross section of the aircraft.

3. The aircraft according to claim 2, wherein the second elongated electrical conductor is arranged in the second structure element in a second orientation, wherein the second orientation is adapted to be aligned parallel to the yaw axis of the aircraft.

4. The aircraft according to claim 1, wherein the second structure element comprises a radar absorbing material.

5. The aircraft according to claim 1, wherein the second structure element comprises a radar absorbing structure.

6. The aircraft according to claim 1, wherein the second structure element comprises a metallic layer.

7. The aircraft according to claim 2, wherein a diameter of the first elongated electrical conductor and/or the second elongated electrical conductor is more than 3 mm.

8. The aircraft according to claim 2, wherein the first elongated electrical conductor and/or the second elongated electrical conductor comprises a coating anti-corrosion and anti-errosion layer.

9. The aircraft according to claim 2, wherein the first elongated electrical conductor and/or the second elongated electrical conductor comprise copper.

10. The aircraft according to claim 2, wherein the first elongated electrical conductor and/or the second elongated electrical conductor comprise aluminium.

11. The aircraft according to claim 2, wherein the first elongated electrical conductor and/or the second elongated electrical conductor comprise a magnetic absorber.

12. The aircraft structural part, according to claim 1, wherein the second structure element comprises an edge.

13. The aircraft according to claim 1, wherein the structural part is wedge-shaped.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The subject matter will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein:

(2) FIG. 1 is a schematic representation of a structural part for lightning strike protection;

(3) FIG. 2 is another schematic representation of a structural part for lightning strike protection according to FIG. 1 with a radar absorbing material and a radar absorbing structure;

(4) FIG. 3 is another schematic representation of a structural part for lightning strike protection according to FIG. 2 with a second and a third electrical conductor;

(5) FIG. 4 is another schematic representation of a structural part for lightning strike protection according to FIG. 3 with a wedge-shaped magnetic absorber;

(6) FIG. 5 is a schematic representation of an aircraft comprising a structural part for lightning strike protection.

DETAILED DESCRIPTION OF THE DRAWINGS

(7) The following detailed description is merely exemplary in nature and is not intended to limit the invention and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description.

(8) The representations and illustrations in the drawings are schematic and not to scale. Like numerals denote like elements.

(9) A greater understanding of the described subject matter may be obtained through a review of the illustrations together with a review of the detailed description that follows.

(10) FIG. 1 shows a schematic representation of a structural part 10 for lightning strike protection. The structural part 10 comprises a first structure element 12, wherein the first structure element 12 comprises a conducting material and is adapted to conduct electric currents into a grounded conducting airframe structure (not shown).

(11) The structural part 10 further comprises a second structure element 14, wherein the second structure element 14 comprises an outer layer with a first surface 16, wherein the outer layer comprises a composite, preferably carbon-fibre reinforced plastic, CFRP or glass-fibre reinforced plastic GFRP. CFRP and GFRP are composite materials. The composite consists of a matrix and a reinforcement. In CFRP the reinforcement is carbon fiber, while in GFRP the reinforcement is glass fibre, each providing the strength. The matrix is usually a polymer resin, such as epoxy, to bind the reinforcements together. Because CFRP and GFRP consist of two distinct components, the material properties depend on these two components.

(12) The first structural part 10 further comprises a first elongated, preferably wedge-shaped, electrical conductor 18, with a first end and a second end, wherein the first end of the first elongated electrical conductor 18 is connected to the first structure element 12 and extends through the second structure element 14 to the first surface 16, so that the second end of the first elongated electrical conductor 18 serves as a lightning receptor without impairing the radar cross section of the aircraft.

(13) FIG. 2 shows a schematic representation of a structural part 10 for lightning strike protection according to FIG. 2. The structural part 10 further comprises a radar absorbing material, RAM, 20 and a radar absorbing structure, RAS, 22, preferably a dielectric layered structure. The RAM 20 is arranged on the RAS 22 between the outer layer 16 and the first structure element.

(14) FIG. 3 shows a schematic representation of a structural part 10 for lightning strike protection according to FIG. 2. The structural part 10 further comprises a second elongated, preferably wedge-shaped, electrical conductor 24 with a first end and a second end, wherein the first end of the second elongated electrical conductor 24 is connected, similar to the first elongated electrical conductor 18, to the first structure element 12 and extends through the second structure element 14 to the first surface 16, so that the second end of the second elongated electrical conductor 24 serves as a lightning receptor without impairing the radar cross section of the aircraft. The first elongated electrical conductor 18 is arranged in the second structure element 14 in a first orientation, wherein the first orientation is adapted to be aligned parallel to the rolling axis of the aircraft. The second elongated electrical conductor 24 is arranged in the second structure element 14 in a second orientation, wherein the second orientation is adapted to be aligned parallel to the yaw axis of the aircraft. There may be additional elongated, preferably wedge-shaped, electrical conductors, exemplary shown by a third elongated electrical conductor 26. The orientation is preferably aligned with the expected incident angle of the radar beam.

(15) FIG. 3 shows a schematic representation of a structural part 10 for lightning strike protection according to FIG. 3. The second elongated electrical conductor 24 comprises a wedge-shaped magnetic absorber 28. The magnetic absorber 28 comprises magnetic particles and preferably surrounds the second elongated electrical conductor 24. The wall thickness may vary or may be constant along the axis of the elongated electrical conductor. The second elongated electrical conductor 24 is only exemplary. The magnetic absorber 28 may also applied to the first elongated electrical conductor 18 or the second elongated electrical conductor 24.

(16) FIG. 4 shows a schematic representation of an aircraft 50 comprising a structural part 10 for lightning strike protection. In this embodiment the structural part 10 is a wing. Other examples of aircrafts include airplanes, helicopters, airships, gliders, paramotors or drones.

(17) While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the invention. It will be understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the claims.

(18) Additionally, it is noted that comprising or including does not exclude any other elements and a or an does not exclude a multitude or plurality. It is further noted that features which are described with reference to one of the above exemplary embodiments may also be used in combination with other features of other exemplary embodiments described above. Reference signs in the claims are not to be construed as a limitation.

(19) While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms comprise or comprising do not exclude other elements or steps, the terms a or one do not exclude a plural number, and the term or means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.

LIST OF REFERENCE SIGNS

(20) 10 structural part 12 first structural element 14 second structural element 16 first surface 18 first elongated electrical conductor 20 radar absorbing material 22 radar absorbing structure 24 second elongated electrical conductor 26 third elongated electrical conductor 28 magnetic absorber 50 aircraft