Patent ID: 12214881

Wherever possible, the same reference numbers will be used throughout the drawing(s) and accompanying written description to refer to the same or like parts. As used in this patent, stating that any part (e.g., a layer, film, area, or plate) is in any way positioned on (e.g., positioned on, located on, disposed on, or formed on, etc.) another part, means that the referenced part is either in contact with the other part, or that the referenced part is above the other part with one or more intermediate part(s) located therebetween. Stating that any part is in contact with another part means that there is no intermediate part between the two parts.

DESCRIPTION

Aircraft employ a flight deck door as a primary barrier protecting a flight deck (e.g., a cockpit) from unauthorized entry and/or intrusion. For instance, in a closed position, the primary barrier is designed to effectively withstand attacks from intruders and/or unauthorized entry. Thus, the primary barrier provides a primary secured area (e.g., the flight deck) when the primary barrier is in a closed position. However, a security threat can be presented during flight when the primary barrier is an open position to allow entry and/or exit of authorized personnel between the flight deck and a passenger cabin of the aircraft (e.g., when a flight attendant brings food or beverages for the pilots, etc.), when the pilot(s) use the lavatory (which is located outside of the flight deck and shared with passengers), etc. Thus, in some instances, a primary barrier in an open position during flight can present a security risk.

To reduce security risks when the primary barrier is in an open position during flight, aircraft often employ a secondary barrier. The secondary barrier forms a secondary secured area between a cabin area in which passengers are present and the primary barrier (e.g., a flight deck door). The secondary secured area provided by the secondary barrier often includes one or more monuments of an aircraft such as, for example, a lavatory, a closet, a galley, and/or other amenities that can be used by pilots or other authorized personnel during flight when the secondary barrier is in a secured position.

Typically, the secondary barrier is a secondary door that is attached to a frame. The frame attaches to the side walls and a ceiling of the aircraft and remains visible when the secondary door is in an open position and a closed position. For instance, the frame includes a first side that attaches to a first monument (e.g., a first wall), a second side that attaches to a second monument (e.g., a second wall) opposite the first monument, and a third side interconnecting the first side and the second side that attaches to the ceiling. The secondary door pivotally couples to the first side of the frame via one or more hinges and latches with the second side of the frame when the secondary door is in the closed position. These secondary doors, although effective at providing a secondary barrier, are visible when not in use and are aesthetically unappealing. Additionally, the frame and doors add significant weight to the aircraft.

Example secondary flight deck barriers disclosed herein provide protection against security risks and significantly reduce weight compared to traditional secondary barriers. Additionally, example secondary flight deck barriers disclosed herein are not visible when stowed or not in use (e.g., in a closed position). Specifically, example secondary flight deck barriers disclosed herein are embedded or integrated in a structural component of the aircraft. In some examples, the secondary barriers disclosed herein are formed with and/or coupled to a wall or monument of the aircraft cabin. Example secondary barriers disclosed herein provide a slide out gate movable between a use or deployed position and a non-use or stowed position relative to the a structural component (e.g., a monument or wall) of the aircraft to which the secondary flight deck barrier is coupled.

FIG.1illustrates an example aircraft100that can be implemented with a secondary barrier system in accordance with teachings of this disclosure. The aircraft100of the illustrated example includes a first aircraft wing102(e.g., a first airfoil) and a second aircraft wing104(e.g., a second airfoil) that extend from a fuselage106. A first aircraft engine110is supported by the first aircraft wing102and a second aircraft engine112is supported by the second aircraft wing104.

FIG.2is a top, partial cutaway view of an example interior or cabin201of the fuselage106of the aircraft100ofFIG.1. The fuselage106of the illustrated example is implemented with an example secondary barrier200disclosed herein. The fuselage106of the illustrated example includes a passenger area202(e.g., a passenger cabin), a flight deck204and a crew area206between the passenger area202and the flight deck204. The crew area206includes a galley208, a closet210, a first lavatory212, a second lavatory214(e.g., an infant changing area) and/or other amenities that can be used by the flight crew and/or pilots. The crew area206is defined by a plurality of monuments216that include walls, cabinets, etc. Specifically, a first monument218and a second monument220form an aisle222that provides a pathway between the flight deck204, the crew area206and the passenger area202. The aisle222provides passengers located in the passenger area202access the crew area206to use one or more amenities located in the crew area206. Additionally, the aisle222provides access between the crew area206and the flight deck204. The first monument218of the illustrated example is a cabinet, wall, and/or other structure in the cabin201. Specifically, the first monument218is at least partially in the crew area206.

To restrict unauthorized access to the flight deck204during flight (e.g., via the aisle222), the aircraft100of the illustrated example includes a first or primary barrier224. As shown in the illustrated example, the primary barrier224is in an example closed position226. During flight, the primary barrier224is typically in the closed position226. The primary barrier224of the illustrated example is a flight deck door228that protects the flight deck204(e.g., a cockpit) from unauthorized entry and/or intrusion. For instance, the flight deck door228is designed to effectively withstand attacks from intruders and/or unauthorized entry into the flight deck204. In other words, the primary barrier224(e.g., the flight deck door228) provides a primary secured area232(e.g., the flight deck) when the primary barrier224is in the closed position226. Passengers in the passenger area202are prevented or restricted from accessing the flight deck204via the primary barrier224. When the primary barrier224is in the closed position226, the secondary barrier200can be positioned in a stowed position230as shown inFIG.2to allow access to amenities of the crew area206via the aisle222. In other words, when the secondary barrier200is in the stowed position230, passengers from the passenger area202can move freely into the aisle222to use the first lavatory212, the second lavatory214, and/or any other amenities in the crew area206.

FIG.3is a partial, cutaway view of the example aircraft100similar toFIG.2but shown with the primary barrier224in an example open position302and the secondary barrier200in an example deployed position304. During flight, the primary barrier224(e.g., the flight deck door228) can move to the open position302to allow flight deck crew in the flight deck204access to the crew area206. However, when the primary barrier224is the open position302to allow entry and/or exit of authorized personnel between the flight deck204and the crew area206, the flight deck204can be exposed to the passenger area202of the aircraft100. Thus, moving the primary barrier224to the open position302during flight can cause a security risk in some instances.

To prevent or reduce a security risk when the primary barrier224is in the open position302, the aircraft100of the illustrated example includes the secondary barrier200. The secondary barrier200of the illustrated example is formed with or coupled to the first monument218. Specifically, the secondary barrier200of the illustrated example is slidably coupled to the first monument218and extends across the aisle222to engage the second monument220when the secondary barrier200is in the deployed position304. In some examples, the secondary barrier200can be slidably coupled to the second monument220and extends across the aisle222to engage the first monument218in a deployed position.

As described in greater detail below, the secondary barrier200extends across the aisle222between the first monument218and the second monument220to block or restrict access to the flight deck204via the aisle222(e.g., to prevent unauthorized access to the flight deck204when the primary barrier224is in the open position302). Thus, the secondary barrier200forms a secondary secured area306between the passenger area202in which passengers can be present and the crew area206(e.g., when the primary barrier224is in the open position302). In other words, the secondary secured area306includes the flight deck204and at least a portion of the aisle222of the crew area206leading to the primary barrier224and the flight deck204. The secondary barrier200secures (e.g., isolates) the flight deck204from the passenger area202. Thus, the secondary barrier200eliminates or prevents security risks and/or enables flight crew and/or other authorized personnel to use the first lavatory212, the closet210and/or other amenities during flight when the secondary barrier200is in the deployed position304and the primary barrier224is in the open position302. In some examples, the secondary barrier200can be positioned to the deployed position304when the primary barrier224is in the closed position226(FIG.2) to prevent or restrict access to the crew area206via the aisle222.

FIG.4is an exploded view of the example secondary barrier200disclosed herein. The secondary barrier200of the illustrated example is a gate400. Specifically, the gate400of the illustrated example is to be slidably coupled to the first monument218of the cabin201. In some examples, the secondary barrier200can be slidably coupled to the second monument220(FIG.2) and/or any other monument or structure of the aircraft100. The secondary barrier200of the illustrated example includes a plurality of rail assemblies401. The rail assemblies401include a plurality of tracks402(e.g., rails) and a plurality of rods404. The secondary barrier200includes a panel406. The tracks402are to mount to the first monument218of the passenger area202. For example, the tracks402of the illustrated example are coupled to (e.g., mounted in) an internal cavity408defined by an inner surface410of the first monument218. In some examples, the tracks402of the illustrated example can be fixed or mounted to the inner surface410via one or more fasteners (e.g., L-brackets, mounting brackets, clips, bolts, screws, clamps, and/or any other suitable fastener(s). In some examples, the tracks402can be integrally formed with the first monument218. For instance, the tracks402can be formed by cutting slots, openings, channels and/or any other apertures in the first monument218. For example, the first monument218can be a solid structure (e.g., a solid wall formed without an internal cavity408) and the tracks402can be defined by a plurality of apertures or openings formed in the solid structure of the first monument218.

The rods404of the illustrated example slidably couple to the tracks402. For instance, respective ones of the rods404slidably couple or slidably engage respective ones of the tracks402. The panel406is coupled (e.g., fixed) to respective ends412of the rods404. For example, the panel406can be welded, fastened and/or integrally formed with the respective ends412of the rods404. Thus, the rods404and the panel406move relative to the tracks402. In this manner, movement of the panel406causes movement of the rods404relative to the tracks402. The panel406of the illustrated example is a metallic strip cap. The tracks402and the rods404can be composed of metal, aluminum, titanium, plastic, alloy and/or any other material(s).

The tracks402of the illustrated example guide the rods404during movement. For example, the tracks402maintain a longitudinal axis414of the rods404in substantial alignment (e.g., horizontal or parallel alignment) with a longitudinal axis416of the tracks402. In other words, the tracks402maintain the longitudinal axis414of the rods404substantially parallel relative to the longitudinal axis416of the tracks402. As used herein, substantially parallel means perfectly parallel (e.g., zero degrees of deviation between the longitudinal axis414and the longitudinal axis416) and almost perfectly parallel (e.g., between 0.1 and 5 degrees of deviation between the longitudinal axis414and the longitudinal axis416). For instance, in the orientation ofFIG.4, the longitudinal axis414and the longitudinal axis416are horizontal relative to the ground. Each of the tracks402of the illustrated example has a rectangular cross-sectional shape. In the illustrated example, the tracks402include a plurality of openings418to slidably receive the rods404. Each opening418has a circular cross-sectional shape. Each of the rods404of the illustrated example has a circular cross-sectional shape to interface with the openings418of the tracks402. For example, a diameter of each of the rods404is smaller than a diameter of each of the openings418. In other examples, the tracks402, the openings418and/or the rods404can have a square cross-sectional shape and/or any other cross-sectional shape.

As discussed in greater detail below, a first rail assembly419of the secondary barrier200includes a lock420. The lock420is to prevent movement of the secondary barrier200(e.g., and/or the rods404relative to the tracks402) when the secondary barrier200is in the deployed position304. The lock420of the illustrated example is formed by an interface between a first track402aand a first rod404aof the first rail assembly419. In some examples, a second rail assembly422can include a lock (e.g., the lock420). In some examples, a third rail assembly and/or any number of rail assemblies401can include locks.

FIG.5is a cross-sectional side view of the secondary barrier200shown in the stowed position230. In the stowed position230, a respective one of the rods404is positioned (e.g., fully or completely positioned) in the opening418of a respective one of the tracks402. The tracks402maintain the rods404substantially parallel relative to the tracks402such that the longitudinal axis414of respective ones of the rods404is aligned (e.g., coaxially aligned) with the longitudinal axis416of respective ones of the tracks402. Additionally, the panel406of the illustrated example is recessed relative to the first monument218. For example, the first monument218includes a slot502to receive the panel406. In this manner, an outer surface504of the panel406is flush or aligned with a first wall or an outer surface506of the first monument218. To move the secondary barrier200, the panel406of the illustrated example includes a grip or handle508. The handle508of the illustrated example is a recess or recessed pocket formed in the panel406so that the handle508does not protrude outwardly or away from the outer surface504of the panel406(e.g., in a direction away from the rods404or the tracks402). Thus, the outer surface504of the panel406has a substantially flat surface. In the illustrated example, the lock420is in an unlocked position510to enable movement of the secondary barrier200to the deployed position304.

FIG.6is a cross-sectional side view of the secondary barrier200disclosed herein shown in the deployed position304. In the deployed position304, the panel406and the rods404extend from (e.g., the openings418of) the tracks402and/or from the first monument218. For instance, the rods404and/or the panel406extend in a direction (e.g., in a sideways direction602) away from the first monument218and the tracks402. The sideways direction602of the illustrated example is a direction along (e.g., a direction substantially parallel relative to) the longitudinal axis416of the tracks402. For instance, movement of the panel406away from the first monument218causes the rods404to move in a direction away from the tracks402along the longitudinal axis416. In other words, the rods404at least partially extend (e.g., extract) from the openings418of the tracks402.

In the deployed position304of the illustrated example, the lock420is in a locked position600to prevent movement of the secondary barrier200from the deployed position304to the stowed position230. In other words, the lock420prevents movement of the rods404relative to the tracks402from the deployed position304to the stowed position230when the lock420is in the locked position600. To enable the lock420to move to the locked position600, (e.g., an end of) the first rod404aof the illustrated example is pivotally coupled to the panel406via a pivot604(e.g., a pivot joint, a ball joint, etc.). The pivot604enables the first rod404ato pivot relative to the panel406such that a longitudinal axis606of the first rod404ais angled relative to the longitudinal axis414of the rods404that do not include the lock420. In other words, the longitudinal axis606of the first rod404awhen the first rod404ais in the deployed position304is angled relative to the longitudinal axis414of the first rod404awhen the first rod404ais in the stowed position230. Thus, the first rod404a, via the pivot604, enables at least a portion of the rod to move in a direction608in the orientation ofFIG.6(e.g., a vertical direction, or a non-parallel or a perpendicular direction relative to the sideways direction602).

Thus, the lock420is movable between the locked position600and the unlocked position510. In the illustrated example, the lock420automatically moves to the locked position600when the secondary barrier200is in the deployed position304. However, the lock420is to be moved manually from the locked position600to the unlocked position510when the secondary barrier200moves from the deployed position304to the stowed position230.

The lock420is inconspicuous or concealed from view when the secondary barrier200is in the deployed position304as shown inFIG.6. For example, the first rod404ahas a slight taper of between approximately 0.5 degrees and 5 degrees from horizontal. This gradual taper can be difficult to detect by the human eye. Thus, although the first rod404amay not be perfectly parallel relative to the other rods404, the first rod404acan be indistinguishable from the other rods404when in the lock420is in the locked position. In some examples, a brush seal or other seal or cap can be positioned within the slot502to conceal the location of the lock. Such a seal can prevent identification of a location of the lock420(e.g., the first rod404a) by a passenger in the passenger area202. Thus, only authorized personnel would be able to determine which one of the rods404includes the lock420.

In some examples, a control system can be employed to automatically move the secondary barrier200between the deployed position304and the stowed position230. In some examples, the control system can be employed to move the secondary barrier200between the stowed position230and the deployed position304based on a position of the primary barrier224. Additional details of how the lock420moves between the locked position600and the unlocked position510are described below inFIGS.10A,10B,11A and11B.

FIG.7is partial, perspective view of the example crew area206ofFIG.2with the secondary barrier200shown in the example stowed position230. In the stowed position230, the secondary barrier200is positioned within the first monument218of the crew area206. Specifically, the rods404are positioned inside the first monument218when the secondary barrier200is in the stowed position230. For instance, the rods404and the tracks402are completely positioned within the first monument218and are not visible to passengers in the passenger area202(FIG.2). In some examples, the only portion of the secondary barrier200that is visible to passengers in the passenger area202when the secondary barrier200is in the stowed position230is the outer surface504of the panel406. In other words, the secondary barrier200is hidden from view when in the stowed position230and, thus, is aesthetically appealing.

The panel406of the illustrated example is flush relative to the outer surface506of the first monument218. In this manner, the outer surface504of the panel406and the outer surface506of the first monument218form a substantially continuous overall outer surface or first wall700(e.g., an outer wall) when the secondary barrier200is in the stowed position230. As used herein, “substantially continuous” means that the outer surface504of the panel406and the first wall700of the first monument218do not form a raised surface or discontinuous surface at or across an interface702between the panel406and the first monument218. In other words, the outer surface506of the first monument218and the outer surface504of the panel406define the first wall700of the first monument218. Thus, the panel406is to define at least a portion of the first wall700of the first monument218when the secondary barrier200is in the stowed position230. In the stowed position230, the secondary barrier200enables access to the crew area206via the aisle222.

FIG.8is another partial, perspective view of the crew area206of the example aircraft100ofFIGS.1-7. Specifically, a second surface or second wall802of the second monument220of the crew area206is shown inFIG.8. The second wall802of the second monument220is opposite the outer surface506of the first monument218. In the deployed position304, the secondary barrier200engages the second surface of the second monument220.

FIG.9is a side view of the example crew area206with the secondary barrier200shown in the deployed position304. As noted above, the secondary barrier200is movable relative to the first monument218between the deployed position304and the stowed position230. Specifically, the secondary barrier200is to extend between the first wall700(FIG.7) or the outer surface506of the first monument218and the second wall802(FIG.8) opposite the first wall700. In the deployed position304, the panel406interfaces with the second monument220opposite the first monument218. In the deployed position304, the rods404extend between the first monument218and the second monument220. The second wall802provides a brace for the panel406when the secondary barrier200is in the deployed position304. In other words, the secondary barrier200(e.g., the gate300) extends between the first monument218and the second monument220to block access to the primary barrier224via the aisle222. As further described inFIGS.10A,10B,11A and11B, the lock420prevents movement of the secondary barrier200between the deployed position304and the stowed position230when the lock420is in the locked position600(FIG.6).

FIG.10Ais a perspective, exploded view of the first rail assembly419and the lock420ofFIG.3.FIG.10Bis a perspective view of the first rail assembly419and the lock420shown in the unlocked position510. The lock420of the illustrated example is formed (e.g., integrally formed) with the first rod404aand the first track402a. Specifically, the lock420is formed by a keyed interface1000defined by the first rod404aand the first track402aassociated with the first rod404a. The keyed interface1000includes a protrusion1002formed on the first rod404aand an opening1004formed in the first track402a. The protrusion1002of the illustrated example is an annular cylindrical or body1006formed on an outer surface1008of the first rod404a. For example, the outer surface1008of the first rod402ahas a first diameter1010(FIG.10A) and the protrusion1002has a second diameter1012(FIG.10B) greater than the first diameter1010. The protrusion1002of the illustrated example includes a stop1014(e.g., a flat surface) and a tapered portion1016.

The opening1004includes a first aperture1018and a second aperture1020. The first aperture1018and the second aperture1020form a key-hole shape. The first aperture1018is sized (e.g., has a diameter) to enable the protrusion1002to pass through the opening1004. The second aperture1020is sized (has a diameter or area) to prevent passage of the protrusion1002through the opening1004. Thus, the first aperture1018has a first area (e.g., diameter) that is greater than the first diameter1010of the first rod404aand the second diameter1012of the protrusion1002. Additionally, the second aperture1020has a second area (e.g., a diameter) that is less than the second diameter1012of the protrusion and greater than the first diameter1010of the first rod404a. The second aperture1020enables the first rod404ato move relative to the first track402ain the direction608non-parallel (e.g., perpendicular to or vertical) relative to the longitudinal axis416of the first track402a.

During operation, the opening418(FIGS.4and5) of the first track402amaintains or guides the first rod404ain substantial alignment (e.g., coaxial alignment) with the first aperture1018until the protrusion1002exits the opening418of the first track402a. As the protrusion1002exits the opening418of the first track402avia the first aperture1018, an end1022of the first rod404amoves in the direction608and into the second aperture1020to the locked position600. For example, gravity can automatically cause the end1022of the first rod404ato move into the second aperture1020as the protrusion1002exits the first track402a. In the locked position600, the stop1014(e.g., a flat surface or an end of the protrusion1002) engages an outer surface1024of the first track402a, providing an interference to prevent movement of the first rod404atoward the stowed position230along the longitudinal axis416of the first track402a. The first track402aprevents movement of the first rod404atoward the stowed position230when the stop (e.g., an end) of the protrusion1002is in direct engagement with the outer surface1024of the first track402aadjacent the second aperture1020.

FIG.11Ais a cross-sectional side view of the first rail assembly419with the lock420shown in the unlocked position510.FIG.11Bis a cross-sectional side view of the first rail assembly419shown with the lock420in the locked position600. The lock420prevents movement of the secondary barrier200in the direction602parallel relative to the longitudinal axis416of the first track402awhen the secondary barrier200is in the deployed position304. In operation, the first rod404ais to allow movement of the secondary barrier200from the deployed position304to the stowed position230when the longitudinal axis414of the first rod404ais substantially parallel and/or substantially aligned (e.g., exactly coaxially aligned or approximately coaxially aligned) relative to the longitudinal axis416of the first track402a. The first rod404ais to prevent movement of the secondary barrier200from the deployed position304to the stowed position230when the longitudinal axis414of the first rod404ais not substantially parallel (e.g., is non-parallel or at an angle that is greater than between 1 degree and 5 degrees) relative to the longitudinal axis416of the first track402a. When the protrusion1002of the first rod1002aexits the opening1004of the first track402a, the first rod404amoves (e.g., automatically via gravity) in the direction608non-parallel (e.g., a downward direction in the orientation ofFIG.11B) relative to the longitudinal axis416of the first track402ato move the lock420from the unlocked position510to the locked position600. For example, the end1022of the first rod404amoves from the first aperture1018to the second aperture1020of the opening1004(FIGS.10A and10B). In the locked position600, the stop1014of the protrusion1002engages (e.g., directly engages) the outer surface1024of the first track402ato prevent movement of the first rod404arelative to the first track402a.

To move the lock420to the unlocked position510and move the secondary barrier200to the stowed position230, the first rod404ais moved in the direction608(e.g., non-parallel or perpendicular) relative to the longitudinal axis416of the first track402a. Specifically, the end1022of the first rod404ais moved in upward in the orientation ofFIGS.11A and11Bto align (e.g., coaxially align) the longitudinal axis414of the first rod404aand the longitudinal axis416of the first track402a. In other words, the first rod404ais repositioned to align with the first aperture1018of the opening1004. In some examples, a user (e.g., a pilot, authorized personnel) can move the first rod404amanually in the direction608to move the lock420from the locked position600to the unlocked position510.

In some examples, the lock420can operate (e.g., be positioned) between the locked position600and the unlocked position510via a control system that includes a controller and a motor (e.g., an actuator) operatively coupled to the lock420that can move the secondary barrier200in the direction602(e.g., a sideways direction) via a transmission or gear train and/or move the first rod404ain the direction608between the locked position600and the unlocked position510. In some examples, the control system can automatically move the secondary barrier200to the stowed position230when the primary barrier224is in the closed position226. In some examples, the control system can automatically move the secondary barrier200to the deployed position304when the primary barrier224moves to the open position302. In some examples, the lock420can be an actuator (e.g., a hydraulic or air operated actuator) that can maintain or lock the secondary barrier200in the deployed position304and prevent unauthorized movement of the secondary barrier200toward the stowed position230when the primary barrier224(FIG.2) is in the open position302. In such examples, the lock420is not provided. Additionally, although the first rod404aof the illustrated example can pivot to move the end1022in the direction608(e.g., a vertical direction) to move the lock420between the unlocked position510and the locked position600, the first rod404amaintains a substantially straight profile relative to the other rods404so that the lock420is discrete. Thus, only authorized personnel would be informed of which one of the rods404of the secondary barrier200includes the lock420. In some examples, two or more rods404can include the lock420. In some examples, a user input (e.g., a pin code via a keypad, facial recognition, etc.) can be provided to enable movement of the lock420from the locked position600to the unlocked position510.

FIG.12Ais a perspective view of the second monument220of the aircraft100ofFIG.1.FIG.12Bis a top view ofFIG.12A. Specifically, a retainer1200is provided on the second wall802of the second monument220. For example, the retainer1200is fastened or attached to a frame of the second monument220via one or more fasteners, a weld, etc. The retainer1200of the illustrated example is to interface with the panel406to retain the panel406and, thus, the secondary barrier200in the deployed position304. Additionally, the retainer1200prevents or restricts movement of the secondary barrier200in a fore-aft direction1202(e.g., a horizontal direction toward the primary barrier224ofFIG.2). For example, the fore-aft direction1202is substantially perpendicular (e.g., perfectly perpendicular or within 1 degree of perfect perpendicularity) relative to the direction602(e.g., the sideways direction) and the direction608(e.g., the vertical direction) ofFIG.6. Additionally, the retainer1200of the illustrated example restricts movement of the secondary barrier200toward the stowed position230when the retainer1200retains the secondary barrier200in the deployed position304. In some examples, the retainer1200and the panel406provide a lock interface1204. For example, the lock interface1204can include an aperture1206formed through a portion1208of the retainer1200and a lip1210of the panel406to receive a shackle of a lock (e.g., a pad lock). In some such examples, the lock interface1204is omitted. The retainer1200of the illustrated example includes a base1212and side walls1214protruding from the base1212to define a cavity1216that receives the panel406.

FIG.13is a top view of a portion of an aircraft cabin1301of an aircraft1302implemented with another example secondary barrier1300(e.g., a gate) disclosed herein. In the illustrated example, the secondary barrier1300is a barrier module1304(e.g., a unitary unit or assembly). In some examples, the barrier module1304can be retrofit to aircraft in the field. The secondary barrier1300of the illustrated example includes a housing1306that couples (e.g., attaches) to a monument1308(e.g., the first monument218, a wall, etc.) of the aircraft1302. Thus, the secondary barrier1300of the illustrated example is a self-contained unit or assembly that can be installed in an aircraft by attaching the housing1306to a first wall1309of the aircraft cabin1301. The secondary barrier1300prevents access to a primary barrier224via an aisle222when the primary barrier is an open position302and the secondary barrier1300is in a deployed position1310. In the deployed position1310, the secondary barrier1300extends from the housing1306across the aisle222and engages a second wall1312of a second monument1314.

FIG.14Ais a perspective view of the secondary barrier1300shown in an example stowed position1402.FIG.14Bis a perspective view of the secondary barrier1300shown in the example deployed position1310. Referring toFIGS.14A and14B, the secondary barrier1400includes a plurality of tracks1404and a plurality of rods1406(e.g., defining a gate). The tracks1404of the illustrated example are positioned within the housing1306. Specifically, the tracks1404of the illustrated example are slots or openings formed in the housing1306between a first side edge1408and a second side edge1410opposite the first side edge1408. Respective ones of the rods1406slidably couple to respective ones of the tracks1404. A panel1412is coupled to respective ends of the rods1406. The panel1412enables movement of the rods1406relative to the tracks1404between the stowed position1402and the deployed position1310. The rods1406in the stowed position1402are positioned entirely (e.g., completely) within the housing1306(e.g., such that the rods1406are not visible to a passenger in a passenger area of the aircraft1302). The rods1406in the deployed position extend externally from the housing1306. The panel1412is an extension of the housing1306and defines an outer wall1414of the housing1306when the panel1412is in the stowed position1402. In some examples, the secondary barrier1300includes a lock (e.g., the lock420) to prevent movement of the panel1412relative to the housing1306when the panel1412is in the deployed position1310and the lock is in a locked condition. The lock can be provided by a key interface (e.g., the key interface or lock420ofFIG.4) formed between a first rod1406aand a first track1404a. In some examples, operation of the secondary barrier1300can be controlled by a control system operatively coupled to the secondary barrier1300.

FIG.15is a flowchart representative of a method for forming or installing a secondary barrier in an aircraft. The installation process described can be performed during manufacturing of an aircraft or retrofitting existing aircraft in the field. The method begins at block1502by attaching a plurality of tracks402to a surface defining a cavity of at least one of a housing1306or a monument (e.g., the first monument218) located in an aircraft cabin201,1301of an aircraft100,1302. In some examples, the cavity is formed in the first monument218of the aircraft100. In some examples, a plurality of slots or openings1004are formed in (e.g., the first wall700) the first monument218to receive respective ones of the tracks402. The tracks402can be attached via fasteners, brackets, welding, chemical fasteners, and/or any other fasteners. In some examples, the tracks1404can be integrally formed with the at least one of the housing1306or the first monument218. After the tracks402,1404are installed, a plurality of rods404,1406are slidably coupled to corresponding ones of the tracks402,1404. (block1504). A panel406,1412is then coupled to respective ends of the rods404,1406(block1506). In some examples, a recess or a slot502is formed in the housing1306or the first monument218to enable the panel406,1412to flush mount with the at least one of the housing1306or the first monument218when the secondary barrier200,1300is in the stowed position230,1402. In some examples, a retainer1200is attached to the second wall802of a second monument220of a cabin201opposite the first monument218.

Although each example secondary barrier200and1300disclosed above has certain features, it should be understood that it is not necessary for a particular feature of one example to be used exclusively with that example. Instead, any of the features described above and/or depicted in the drawings can be combined with any of the examples, in addition to or in substitution for any of the other features of those examples. Features of one example are not mutually exclusive to features of another example. Instead, the scope of this disclosure encompasses any combination of any of the features. In some examples, the secondary barrier200can be used in conjunction with the secondary barrier1300. In some examples, one or more of the components of the secondary barrier200(e.g., the retainer1200, the lock420, etc.) can be used with the secondary barrier1300.

“Including” and “comprising” (and all forms and tenses thereof) are used herein to be open ended terms. Thus, whenever a claim employs any form of “include” or “comprise” (e.g., comprises, includes, comprising, including, having, etc.) as a preamble or within a claim recitation of any kind, it is to be understood that additional elements, terms, etc. may be present without falling outside the scope of the corresponding claim or recitation. As used herein, when the phrase “at least” is used as the transition term in, for example, a preamble of a claim, it is open-ended in the same manner as the term “comprising” and “including” are open ended. The term “and/or” when used, for example, in a form such as A, B, and/or C refers to any combination or subset of A, B, C such as (1) A alone, (2) B alone, (3) C alone, (4) A with B, (5) A with C, (6) B with C, and (7) A with B and with C. As used herein in the context of describing structures, components, items, objects and/or things, the phrase “at least one of A and B” is intended to refer to implementations including any of (1) at least one A, (2) at least one B, and (3) at least one of A and at least one of B. Similarly, as used herein in the context of describing structures, components, items, objects and/or things, the phrase “at least one of A or B” is intended to refer to implementations including any of (1) at least one A, (2) at least one B, and (3) at least one A and at least one B. As used herein in the context of describing the performance or execution of processes, instructions, actions, activities and/or steps, the phrase “at least one of A and B” is intended to refer to implementations including any of (1) at least A, (2) at least B, and (3) at least A and at least B. Similarly, as used herein in the context of describing the performance or execution of processes, instructions, actions, activities and/or steps, the phrase “at least one of A or B” is intended to refer to implementations including any of (1) at least A, (2) at least B, and (3) at least A and at least B.

From the foregoing, it will be appreciated that the disclosed secondary barriers improve aircraft safety while improving aircraft efficiency by reducing aircraft weight. Additionally, example secondary barriers disclosed herein improve aircraft aesthetics by providing a gate or door-like retractable structure that is not visible when the secondary barrier is in a stowed or open position. Unlike traditional secondary barriers, the secondary barriers disclosed herein do not include a frame that is visible when the secondary barrier is in a non-use position (e.g., an open or a stowed position).

Example 1 is a secondary barrier that includes a plurality of tracks to mount to a first monument in a cabin of an aircraft and a plurality of rods, where respective ones of the rods slidably engage respective ones of the tracks. The secondary barrier includes a panel coupled to respective ends of the rods. The rods to move relative to the tracks between a stowed position and a deployed position. The panel in the deployed position is to interface with a second monument in the cabin opposite the first monument. The rods are to extend between the first monument and the second monument when the secondary barrier is in the deployed position.

Example 2 includes the subject matter of Example 1, where the panel is to define an outer surface of the first monument when the secondary barrier is in the stowed position.

Example 3 includes the subject matter of any one of Examples 1 and 2, where the rods are to be positioned inside the first monument when the secondary barrier is in the stowed position.

Example 4 includes the subject matter of any one of Examples 1-3, where the tracks are fixed to a surface defining a cavity of the first monument.

Example 5 includes the subject matter of any one of Examples 1-4, where the panel is a metallic strip cap movable between the first monument and the second monument.

Example 6 includes the subject matter of any one of Examples 1-5, further including a retainer to couple to the second monument, the retainer to interface with the panel to retain the panel in the deployed position.

Example 7 includes the subject matter of any one of Examples 1-6, further including a lock movable between a locked position and an unlocked position, the lock to prevent movement of the secondary barrier from the deployed position to the stowed position when the lock is in the locked position.

Example 8 includes the subject matter of any one of Examples 1-7, where the lock is formed by a keyed interface defined by a first one of the rods and a first one of the tracks associated with the first rod.

Example 9 includes the subject matter of any one of Examples 1-8, where the keyed interface includes a protrusion formed on the first rod and an opening formed in the first track.

Example 10 includes the subject matter of any one of Examples 1-9, where the protrusion is an annular body defining a stop to engage the first track when the lock is in the locked position.

Example 11 includes the subject matter of any one of Examples 1-10, where the opening includes a first aperture and a second aperture, the first aperture to enable the protrusion to pass through the opening and the second aperture to enable the first rod to move relative to the first track in a direction non-parallel relative to a longitudinal axis of the first track.

Example 12 includes the subject matter of any one of Examples 1-11, where the first track prevents movement of the first rod toward the stowed position when the stop of the protrusion is in direct engagement with an outer surface of the first track adjacent the second aperture.

Example 13 includes the subject matter of any one of Examples 1-12, where the first aperture and the second aperture form a key-hole shape.

Example 14 is a secondary barrier including includes a gate to be slidably coupled to a first wall of an aircraft cabin. The gate is movable between a deployed position and a stowed position. The gate includes a plurality of rails and a panel. The rails to be positioned inside the first wall of the aircraft cabin when the gate is in the stowed position. A retainer is to couple to a second wall. The panel is to interface with the retainer when the gate is in the deployed position. The retainer is to restrict movement of the gate in a direction non-parallel relative to a longitudinal axis of the rails.

Example 15 includes the subject matter of Example 14, further including a lock to prevent movement of the gate in a direction parallel relative to the longitudinal axis when the gate is in the deployed position.

Example 16 includes the subject matter of any one of Examples 14-15, where the lock is integrally formed with one of the rails.

Example 17 includes the subject matter of any one of Examples 14-16, where the rails include a plurality of tracks and a plurality of rods, wherein the lock is formed by an interface between a first one of the tracks and a first one of the rods.

Example 18 includes the subject matter of any one of Examples 14-17, where the first rod is to allow movement of the gate from the deployed position to the stowed position when a first longitudinal axis of the first rod is substantially parallel relative to a first longitudinal axis of a first track, and the first rod is to prevent movement of the gate from the deployed position to the stowed position when the first longitudinal axis of the first rod is not substantially parallel relative to the first longitudinal axis of the first rod.

Example 19 is a method including includes attaching a plurality of tracks to a surface defining a cavity of at least one of a housing or a first monument of an aircraft cabin; slidably coupling a plurality of rods to corresponding ones of the tracks; and coupling a panel to respective ends of the rods.

Example 20 includes the subject matter of Example 19, further including attaching a retainer to a surface of a second monument of an aircraft cabin opposite the first monument.

Example 21 is a secondary barrier including a housing. A plurality of tracks are positioned within the housing and a plurality of rods, where respective ones of the rods to slidably couple to respective ones of the tracks. A panel is coupled respective ends of the rods. The panel is to cause the rods to move between a stowed position and a deployed position. The rods in the stowed position are to be positioned entirely within the housing. The rods in the deployed position are to extend externally from the housing. The panel is to form an outer wall of the housing when the panel is in the stowed position.

Example 22 includes the subject matter of Example 21, further including a lock provided by a key interface formed between a first one of the rods and a first one of the tracks, the lock to prevent movement of the panel relative to the housing when the panel is in the deployed position and the lock is in a locked position.

Although certain example methods, apparatus and articles of manufacture have been described herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus and articles of manufacture fairly falling within the scope of the appended claims either literally or under the doctrine of equivalents.