Arresting hook systems for aircraft

Methods, apparatus, systems, and articles of manufacture are disclosed. An example arresting hook system for an aircraft includes a linkage assembly defining a trapeze deployment assembly of the arresting hook system, a pivot assembly to pivotally couple a hook shank to a primary pivot joint of an aft body, a vertical actuator coupled to a forward body and a frame of the aircraft to move the arresting hook system between a stowed position and an intermediate position, and a vertical damper actuator (VDA) including a cylinder and a piston. The cylinder pivotally coupled to the frame of the aircraft via a VDA pivot joint, the VDA to rotate relative to the frame of the aircraft, the piston having an end operatively coupled to the pivot assembly, the VDA to move the arresting hook system between the intermediate position and a deployed position.

FIELD OF THE DISCLOSURE

This disclosure relates generally to aircraft landing systems and, more particularly, to arresting hook systems for aircraft.

BACKGROUND

Landing strips having abridged runways (e.g., such as Aircraft carriers) can cause aircraft landings to be challenging. Such aircraft typically include arresting hook systems to decelerate the aircraft after landing on an abridged runway.

SUMMARY

An example arresting hook system for an aircraft includes a linkage assembly, a pivot assembly, a vertical actuator, and a vertical damper actuator (VDA). The linkage assembly includes a forward body, an aft body, and a coupling assembly. The forward body defines a first joint and a second joint opposite the first joint. The forward body longitudinally extends between the first joint and the second joint. The forward body is pivotally coupled to a frame of the aircraft via the first joint. The aft body defines a third joint, a fourth joint, and a primary pivot joint. The aft body is pivotally coupled to the frame via the third joint. The coupling assembly is pivotally coupled to the second joint of the forward body and the fourth joint of the aft body. Movement of the forward body is to cause movement of the aft body via the coupling assembly. The pivot assembly is to pivotally couple a hook shank to the primary pivot joint of the aft body. The vertical actuator is coupled to the forward body and the frame of the aircraft. The vertical actuator is to move the arresting hook system between a stowed position and an intermediate position. The VDA includes a cylinder and a piston. The cylinder is pivotally coupled to the frame of the aircraft via a VDA pivot joint. The VDA is to rotate relative to the frame of the aircraft. The piston has an end operatively coupled to the pivot assembly. The VDA is to move the arresting hook system between the intermediate position and a deployed position.

An example arresting hook apparatus to be stowed within an outer mold line of an aircraft includes a trapeze deployment assembly and a hook deployment assembly. The trapeze deployment assembly includes a vertical actuator to move the trapeze deployment assembly between a stowed position and an intermediate position. The hook deployment assembly includes a vertical damper actuator (VDA) and a hook. The VDA is pivotally coupled to a primary structure of the aircraft via a trunnion. The VDA is to move the hook deployment assembly between the intermediate position and a deployed position. The VDA is to dampen arrestment loads when the hook deployment assembly is in the deployed position.

An example aircraft includes an arresting hook system including a hook shank, a hook, a linkage assembly, a vertical actuator, and a vertical damper actuator. The arresting hook system is disposed within an outer mold line of the aircraft when the arresting hook system is in a stowed position. The arresting hook system is disposed at least partially outside of the outer mold line when the arresting hook system is in at least one of an intermediate position or a deployed position. The hook shank has a first end and a second end opposite the first end. The hook is coupled to the first end of the hook shank. The linkage assembly includes a forward body, a coupling, and an aft body. The second end of the hook shank is coupled to the aft body via a primary pivot joint. The forward body is aligned with the coupling when the arresting hook system is in the intermediate position and the deployed position. The vertical actuator is coupled to a frame of the aircraft and the forward body to deploy the arresting hook system between the stowed position and the intermediate position. The vertical damper actuator is pivotally coupled to the frame of the aircraft via a trunnion. The vertical damper actuator is to deploy the arresting hook system between the intermediate position and the deployed position.

As used herein, unless otherwise stated, the term “above” describes the relationship of two parts relative to Earth when an aircraft is resting upon landing gear on the ground. A first part is above a second part, if the second part has at least one part between the Earth and the first part. Likewise, as used herein, a first part is “below” a second part when the first part is closer to the Earth than the second part. As noted above, a first part can be above or below a second part with one or more of: other parts therebetween, without other parts therebetween, with the first and second parts touching, or without the first and second parts being in direct contact with one another.

DETAILED DESCRIPTION

Arresting hook systems are typically a sub-system included in military aircraft and used during landing on aircraft carriers. However, aircraft arresting systems can also be employed with some civilian aircraft and/or military aircraft for use at airports or other land-based unabridged runways. For example, arresting systems are often employed to stop aircraft when landing on an abridged landing strip such, as, for example, an aircraft carrier, a short-length runway, etc. Additionally, arresting systems can also be used at unabridged runways, for example, after a high speed rejected take-off when using unabridged runways. Arresting gear systems include a hook (referred to herein as a “hook point”) which is attached to an end of a hook shank. The hook shank is deployed below an outer mold line (OML) of the aircraft such that the hook point engages with a cable on the runway. As used herein, the “outer mold line” refers to the outer shell of the aircraft.

For instance, to deploy an arresting system during landing, a pilot can lower an arresting hook of an arresting system such that the arresting hook contacts the runway as the aircraft wheels touch down. The hook drags along the surface of the runway and engages with an arresting cable stretched across the runway, transverse to the direction of aircraft travel. The arresting hook system supports arresting loads (e.g., vertical forces, lateral forces, etc.) imposed on the arresting hook. The cable transfers the kinetic energy of the aircraft to an arresting gear system to sufficiently decelerate the aircraft.

Arresting hook systems generally include a hook point, a hook shank, a pivot assembly, an airframe interface (e.g., either fixed or deployable, such as a trapeze), a lateral damper, and vertical damper actuator(s) (VDA(s)). The airframe interface (e.g., the trapeze, the fixed pivot, etc.) couples the pivot assembly and the hook shank to the airframe or primary structure. Some conventional pivot assemblies are configured as a stinger style, which has a short distance between a primary pivot axis (e.g., horizontal or lateral axis) and a vertical pivot axes to minimize the bending moment induced by a side load applied at the vertical pivot axis. Typically, conventional systems with trapezing interfaces also include stinger-style pivot assemblies. As used herein, a “trapeze,” “trapezing structure,” “trapezing interface,” “trapeze assembly,” and/or the like refer to an assembly that can cause the pivot assembly and the hook shank to swing or “trapeze” down below the OML of the aircraft based on actuation from a vertical actuator.

Conventional arresting hook systems (e.g., trapeze-style systems, etc.) may be coupled to and/or mounted on the airframe such that a portion of the system (e.g., the pivot assembly, the hook shank, the hook point, etc.) protrudes beyond or outside the OML when the system is in the stowed position. Some known arresting hook systems include a wrist link as a part of the stinger-style pivot assembly to connect the hook shank and the trapezing structure. However, the vertical axis of stinger-style assemblies is often offset relative to the primary pivot axis of the wrist along a longitudinal axis. In other words, the primary pivot axis does not intersect the vertical axis. Such an offset distance between the vertical and horizontal axes causes large moment forces to transfer to the trapeze assembly. As a result, larger trapeze assemblies are needed to counteract such lateral side-loads and/or moment loads, which is associated with an increased system weight. Furthermore, some known arresting hook systems include a single uplock mechanism to latch the pivot assembly and/or the airframe interface to hold the system in the stowed position. However, such uplock mechanisms do not enable positioning the arresting hook system in an inspection or intermediate position needed for servicing and/or inspecting the hook. The inspection position as described herein is between a fully stowed position and a fully deployed position of the hook.

Example arresting hook systems disclosed herein include multiple pivot axes (e.g., lateral, or horizontal axes) that are parallel to a pitch axis of the aircraft. As used herein, the terms “pivot axis” and “pivot axes” refer to one or more axes about which members of the arresting hook system (e.g., the hook shank, etc.) vertically rotate during deployment and/or arrestment. As used herein, the term “primary pivot axis” refers to an axis of the pivot assembly and the hook shank that is substantially parallel to a pitch axis of an aircraft and/or other pivot axes of the arresting hook system. For example, the VDA can rotate (e.g., vertically lower) the hook shank about the primary pivot axis to move the hook shank into the deployed position. As the hook engages an arresting cable, lateral forces can be applied to the hook shank that influence rotation of the hook shank about a vertical axis of the arresting hook system. As used herein, the term “vertical axis” refers to an axis of the pivot assembly and the hook shank orthogonal to the primary pivot axis. Unlike the pivot axes, the vertical axis is not always parallel to a yaw axis of the aircraft. As the VDA deploys the arresting hook system, the hook shank and/or a longitudinal axis rotates about the primary pivot axis while remaining orthogonal to the primary pivot axis. As used herein, the term “longitudinal axis” refers to an axis of the pivot assembly orthogonal to the primary pivot axis and the vertical axis. The longitudinal axis can be aligned with the hook shank. However, as the hook point engages an arresting cable, lateral forces can be applied to the hook shank that influence rotation of the hook shank about the vertical axis such that an angle is formed between the hook shank and the longitudinal axis. Similar to the vertical axis, the longitudinal axis is not always parallel to a roll axis of the aircraft.

As used herein, the term “lateral damper” refers to a damper (e.g., pneumatic damper, hydraulic damper, etc.) that can support lateral forces and counteract rotation of the hook shank about the vertical axis. As used herein, the term “vertical damper actuator” refers to a mechanism that functions as an actuator (e.g., pneumatic damper actuator, hydraulic damper actuator, etc.) and a damper. The VDA can rotate a member (e.g., the hook shank) about the primary pivot axis as well as support (e.g., counteract, dampen, absorb, etc.) vertical forces acting on the member against the direction of motion. The terms “vertical force,” “vertical load,” and/or “vertical torque” refer to dynamic influences on the hook shank that cause the hook shank to rotate about the primary pivot axis. The terms “lateral force,” “lateral load,” and/or “lateral torque” refer to dynamic influences on the hook shank which cause the hook shank to rotate about the vertical axis. The terms “longitudinal force” and/or “longitudinal load” refer to dynamic influences (e.g., tensile force, compressive forces, etc.) on the hook shank that are aligned with the longitudinal axis.

The hook shank can be coupled to a pivot assembly and the pivot assembly can be coupled to an airframe interface (e.g., trapeze or fixed pivot). The aircraft interface can be coupled to a primary structure and/or an airframe of the aircraft via pivot joints (e.g., rotatable joints). In some examples, the aircraft interface allows movement (e.g., rotation, deployment, etc.) of the hook shank between a stowed position and an intermediate position. Furthermore, in some examples, the pivot assembly allows movement of the hook shank between the intermediate position and the deployed position for arrestment. The pivot assembly and the aircraft interface serve as the structural load path from the hook shank to the primary structure of the aircraft.

Example arresting hook systems disclosed herein employ a trapeze deployment assembly, a hook deployment assembly, a pivot assembly to pivotally couple the trapeze deployment assembly and the hook deployment assembly, and a latching system for securing the hook in the stowed position and an inspection or intermediate position. In some examples, the trapeze deployment assembly employs a vertical actuator to deploy the trapeze deployment assembly. In some examples, the hook deployment assembly employs a VDA (e.g., a trunnion mounted VDA) pivotally coupled to the airframe or primary structure of an aircraft. In known arresting hook systems, the VDA is pivotally coupled to (“rides on”) the airframe interface (e.g., trapeze deployment assembly, etc.) to support vertical loading and to rotate the hook shank about the primary pivot axis from an up/stowed position to a down/deployed position. Disclosed arresting hook systems decouple the VDA from the trapezing assembly such that the VDA is pivotally coupled to primary structure via a trunnion and pivotally coupled to the hook deployment assembly via a piston to improve the damping kinematics of the system. As a result, the trapeze deployment assembly and the hook deployment assembly effectively define two sets of 4-bar linkage assemblies: a first four-bar linkage assembly (a trapezing four-bar linkage) associated with the trapeze deployment assembly and a second four-bar linkage assembly (a damping four-bar linkage) associated with the hook deployment assembly. As used herein, “damping kinematics” refers to the capability of the disclosed arresting hook system to dissipate energy during an arrested landing event. In some examples, the efficiency of the arresting hook system can be measured based on the amount of rotational energy removed from the system per unit of arrestment loads imparted to the hook shank.

The example trapeze deployment assembly, the hook deployment assembly and/or the pivot coupler provide a highly efficient system that has favorable and/or improved VDA kinematics, which reduces weight while improving cable engagement performance, with the system also enabling a reduced VDA stroke length that minimizes weight, installation volume, and deployment complexity. Additionally, decoupling attachment between the VDA and the trapeze deployment assembly simplifies control fluid routing and enables a narrow system envelope in a lateral direction, thereby saving space. Additionally, the trunnion connection provided by the VDA eliminates the design constraint of retracted pin-to-pin length, resulting in a design that is both compact and robust/flexible for a wide variety of design envelopes.

An example pivot coupler assembly (e.g., a pivot assembly) disclosed herein diminishes loads to primary structure(s) of an aircraft. Example couplers disclosed herein employ a zero-length coupling that nearly eliminates a lateral moment into a trapeze supporting the hook. As used herein, “zero-length coupling” means that the lateral axis (e.g., of the hook shank) intersects the primary pivot axis (e.g., of the pivot assembly) so that there is no lateral separation or distance between the lateral axis and the primary pivot axis. As a result of the lateral axis intersecting the pivot axis, no moment arm for a side-load is created, which reduces a moment force that would otherwise need to be reacted by a trapeze assembly. Additionally, some example couplers disclosed herein include a cam surface for the lateral damper (e.g., to act against). This lateral moment, along with friction, are the only lateral axis moments imparted to the trapeze assembly. As a result, the example couplers disclosed herein enable a smaller trapeze, which significantly reduces weight of disclosed systems. An example pivot assembly for an arresting hook disclosed herein includes a cylindrical coupler structured and/or configured to be received within the clevis of an arresting hook shank. The cylindrical coupler has a bore extending in a direction transverse to an axis of the cylindrical coupler for receiving a pin. A linkage arm couples to (e.g., depends from) a shaft extending thru the clevis of the hook shank and cylindrical coupler. The arm extends at an angle relative to the shaft. A pin extends through the cylindrical coupler and the linkage arm shaft and is pivotally coupled to a structure of the trapeze assembly. The axes of the linkage arm shaft and the pin intersect each other.

Some example arresting hook systems disclosed herein employ an uplock or latching system that can robustly retain an example hook in a stowed position. Additionally, the example uplock assembly disclosed herein can maintain the example hook in an intermediate position during inspection. In some examples, uplock assemblies disclosed herein employ a track coupled to a primary or frame structure of an aircraft, a spring latch coupled to a first end of the track, a passive capture feature facing aft located at a second end of the track opposite the first end, and a roller. The roller is coupled to a hook shank and/or the hook. The spring latch can lock a position of the hook shank via engagement between the spring latch and the roller when the hook shaft is retracted after deployment and/or from the deployed position. However, a force of the roller when moving the trapeze deployment assembly to the stowed position enables the roller to detach from the spring latch. During initial deployment from the stowed position to the deployed position, the spring latch system includes a barrier that enables the roller to bypass the spring latch and continue to the fully deployed position. Thus, the spring latch system does not interfere with deployment of the hook deployment assembly from the stowed position to the deployed position.

An example passive capture mechanism for a stowable arresting hook can include a guide member having a forward end portion with a passive capture hook, and an aft end portion with a pivotally mounted bypass element. A bracket is coupled to an arresting hook shank. The bracket includes an end portion having a roller. The roller is structured or configured to roll along the guide between a retracted position within the passive hook and an extended position in which the roller can bypass a directional spring latch mechanism or is captured by the directional spring latch mechanism, depending on the direction of roller movement. For example, when moving from the stowed position to the deployed position, the roller bypasses the directional spring latch mechanism. When moving from the deployed position to the stowed position, the roller is captured by the directional spring latch mechanism to maintain the hook in an intermediate or inspection position (e.g., a partially deployed position).

FIG.1is a side view of an example aircraft100including an example arresting hook system102(e.g., a tailhook) in accordance with teachings of this disclosure. Specifically, the arresting hook system102is positioned and/or stowed in a fuselage104(e.g., within the fuselage104) adjacent an aft region106of the fuselage104. The aircraft100of the illustrated example includes a first or front landing gear108and a second or rear landing gear110for landing and supporting the aircraft100on a ground surface112. The arresting hook system102is located aft of the rear landing gear110. The arresting hook system102of the illustrated example can be deployed to engage a cable extending across a runway transverse to the direction of movement of the aircraft to reduce a braking or stopping distance of the aircraft100during a landing event. For example, the arresting hook system102can be employed when landing on an aircraft carrier. In the illustrated example ofFIG.1, the aircraft100is a military aircraft. However, other example aircraft including civilian aircraft can employ the example arresting hook system102disclosed herein. For example, the arresting hook system102disclosed herein can be employed with any aircraft to achieve rapid deceleration during routine landings aboard aircraft carrier flight decks at sea, or during emergency landings or aborted takeoffs at properly equipped airports (e.g., airports that have cable arrestment systems). The aircraft100of the illustrated example is described herein in reference to a roll axis132of the aircraft100, a yaw axis134of the aircraft100, and/or a pitch axis136of the aircraft100.

FIGS.2A-2Dillustrates the example arresting hook system102ofFIG.1.FIG.2Ais a perspective view of the example arresting hook system102shown in an example stowed position202(e.g., a fully stowed or retracted position).FIG.2Bis a perspective view of the example arresting hook system102shown in an example deployed position204(e.g., fully deployed, or extended position).FIG.2Cis a perspective view of the example arresting hook system102shown in an example intermediate or inspection position206. The inspection position206is between the stowed position202and the deployed position204.FIG.2Dis a top view of the example arresting hook system102ofFIGS.2A-2C.

Referring toFIGS.2A-2C, to move the arresting hook system102between the stowed position202, the deployed position204and the inspection position206, the example arresting hook system102of the illustrated example includes a trapeze deployment assembly208, a hook deployment assembly210, and a pivot assembly212(e.g., a pivot coupler assembly). To assist with retaining the hook in the stowed position202and/or the inspection position206, the arresting hook system102of the illustrated example includes a locking assembly214. In some examples, although not shown, the arresting hook system102of the illustrated example includes a primary lock or uplock (e.g., a primary lock1902ofFIG.19).

The arresting hook system102of the illustrated example includes a first joint216defining a first pivot axis216a, a second joint218defining a second pivot axis218a, a third joint220defining a third pivot axis220a, a fourth joint222defining a fourth pivot axis222a, a fifth joint224defining a fifth pivot axis or a primary pivot axis224a, a sixth joint226defining a sixth pivot axis or a VDA pivot axis226a, and a seventh joint228defining a seventh pivot axis or a VDA-linkage arm pivot axis228a. The joints216-228of the illustrated example can be defined by one of more bushings, bearings, pins, clevis connections, trunnions, and/or any other coupling that enables pivotal movement to define the pivot axes216a-228a. In the illustrated example, the first joint216, the third joint220and the sixth joint226are pivotally coupled to a primary structure or frame230(e.g., airframe, etc.) of the aircraft100. The second joint218, the fourth joint222, the fifth joint224and the seventh joint228are not directly coupled to the frame230. As used herein, the primary structure or frame230of an aircraft includes, but is not limited to, a bulkhead, a stringer, a former, a longeron, a beam and/or any other structure of an aircraft for counteracting loads, forces, moments, etc., imparted to the aircraft100.

The arresting hook system102of the illustrated example is described herein in reference to a longitudinal axis232(e.g., an x-axis), a vertical axis234(e.g., a y-axis), and/or a pivot axis236(e.g., a z-axis). For example, the pivot axes216a-228aof the illustrated example have the same orientation relative to the pivot axis236. In some examples when the arresting hook system102is in between the stowed position202, the deployed position204and the inspection position206, the longitudinal axis232of the illustrated example can be substantially parallel relative to the roll axis132of the aircraft100, the vertical axis234can be substantially parallel relative to the yaw axis134of the aircraft100, and/or the pivot axis236can be substantially parallel relative to the pitch axis136of the aircraft100. As used herein, “parallel” or “substantially parallel” means perfectly parallel or parallel within 10 degrees of perfectly parallel. For example, first pivot axis axes216a, the second pivot axis218a, the third pivot axis220a, the fourth pivot axis222a, the fifth pivot axis224a, the sixth pivot axis226aand the seventh pivot axis228aof the illustrated example are substantially parallel relative to each other and/or the pitch axis136. In some examples when the arresting hook system102is in between the stowed position202, the deployed position204and the inspection position206, the longitudinal axis232of the illustrated example can be non-parallel relative to the roll axis132of the aircraft100and/or the vertical axis234can be non-parallel relative to the yaw axis134of the aircraft100. For example, in some examples, the longitudinal axis232can be at an angle (e.g., between 15 degrees and 90 degrees) relative to the roll axis132. For example, in some examples, the vertical axis234can be at an angle (e.g., between 15 degrees and 90 degrees) relative to the yaw axis134.

The arresting hook system102of the illustrated example can pivot or rotate about the first pivot axis216a, the second pivot axis218a, the third pivot axis220a, the fourth pivot axis222a, the fifth pivot axis224a, the sixth pivot axis226aand/or the seventh pivot axis228ato enable the arresting hook system102to move between the stowed position202, the deployed position204, and/or the intermediate position206.

The trapeze deployment assembly208of the illustrated example includes a first linkage assembly240(e.g., a trapeze) and a vertical actuator242(e.g., a double-acting actuator, etc.). The vertical actuator242of the illustrated example operates the first linkage assembly240and/or the trapeze deployment assembly208. For example, the vertical actuator242causes the first linkage assembly240of the trapeze deployment assembly208to move between a retracted position244(FIG.2A) and an extended position246(e.g.,FIGS.2B and2C). The vertical actuator242of the illustrated example has a first end242athat is coupled or fixed to the frame230of the aircraft100and a second end242bof the vertical actuator242is coupled to the first linkage assembly240.

The hook deployment assembly210of the illustrated example includes a second linkage assembly250and a vertical damper actuator (VDA)252. The VDA252is operatively coupled to the hook deployment assembly210via the pivot assembly212and causes (e.g., deploys) the hook deployment assembly210to move between a non-engagement position254(FIG.2A), an arrestment position256(FIG.2B) (e.g., an engagement position), and a non-engagement intermediate position258(FIG.2C) (e.g., a non-arrestment position) (e.g., in a rotational direction about the primary pivot axis224a).

The pivot assembly212of the illustrated example pivotally couples the trapeze deployment assembly208and the hook deployment assembly210. Additionally, the pivot assembly212of the illustrated example operatively couples the VDA252and the hook deployment assembly210. Thus, operation of the VDA252causes movement of the hook deployment assembly210between the non-engagement stowed position254, the arrestment position256and/or the non-engagement intermediate position258.

The arresting hook system102of the illustrated example is an internally stowed system. As shown inFIG.2A, when the arresting hook system102is in the stowed position202, the arresting hook system102is housed within a bay or opening260of the fuselage104such that no part of the arresting hook system102protrudes beyond an outer mold line (OML)262of the fuselage104. That is, when the arresting hook system102is in the stowed position202, the trapeze deployment assembly208, the hook deployment assembly210and the pivot assembly212are disposed above (e.g., within) the OML262and/or within the fuselage104of the aircraft100. In some examples, the arresting hook system102can include an uplock mechanism (e.g., the primary lock1902ofFIG.19) that interfaces directly with the trapeze deployment assembly208. The uplock mechanism may be a locking actuator that latches onto a hook of the trapeze deployment assembly208. Additionally or alternatively, the hook deployment assembly210engages with (e.g., snaps into, interfaces with, etc.) the locking assembly214when the arresting hook system102is in the stowed position202and/or the inspection position206. The arresting hook system102of the illustrated example can be deployed to at least partially extend beyond or outside of (e.g., below) the OML262when the arresting hook system102is in the deployed position204and/or the inspection position206. Thus, the arresting hook system102of the illustrated example is stowed above the lower OML262in-flight and is deployed below the lower OML262to engage a cable (during landing) and/or for inspection.

To enclose the arresting hook system102within the fuselage104when the arresting hook system102is in the stowed position202, the arresting hook system102of the illustrated example includes a cover264. The cover264of the illustrated example seals, covers or encloses the opening260through which the arresting hook system102extends or projects in the deployed position204and/or the inspection position206. In some examples, the cover264defines a portion of an outer surface (e.g., an under belly) of the fuselage104when the arresting hook system102is in the stowed position202. As a result, the cover264improves aerodynamic characteristics of the aircraft100, thereby improving efficiency and performance. The cover264of the illustrated example includes a first door or first panel266and a second door or second panel268. Specifically, the trapeze deployment assembly208includes (e.g., supports) the first panel266and the hook deployment assembly210includes (e.g., supports) the second panel268. In the stowed position202, the first panel266and the second panel268adjoin or engage at least partially enclose the opening260. In other words, the first panel266and the second panel268enclose the arresting hook system102in the fuselage104. In some examples, the cover264can include a third door or panel that covers the hook deployment assembly210and/or the locking assembly214when the arresting hook system102is in the stowed position202. In such examples, the third panel can be hinged about an axis near and/or parallel to the roll axis132of the aircraft. The third panel can be actuated by a separate actuator during hook deployment.

The first panel266has a first end266apivotally coupled to the frame230and a second end266bopposite the first end266apivotally coupled to the first linkage assembly240. The first panel266is pivotally coupled to the frame230via a hinge270at the first end266a. The hinge270includes a pin272to pivotally couple the first end266a(e.g., an arm) of the first panel266and the frame230. The second end266bof the first panel266is coupled to the trapeze deployment assembly208(e.g., the first linkage assembly240) via a tether or rod274(e.g., a rigid or adjustable rod). The second panel268is fixed to the second linkage assembly250via fasteners276(e.g., bolts, pins, etc.). In the illustrated example, the cover264is coordinated with the arresting hook system102. Thus, the cover264moves between a cover closed position278(FIG.2A) when the arresting hook system102is in the stowed position202and a cover open position279(FIG.2B) when the arresting hook system102is in the deployed position204. In contrast to known arresting hook systems that employ mechanized doors that include actuators, which add significant complexity, weight, and cost to the arresting hook system and the trapezing actuation thereof, the arresting hook system102of the illustrated example employs primarily passive or follower doors that are not actuated by separate actuators and/or systems but follow movement of the arresting hooks system102.

Referring toFIG.2D, the first linkage assembly240is pivotally coupled to the frame230via a first set of pins280(e.g., and/or bushings) and a second set of pins282(e.g., and/or bushings) spaced from the first set of pins280. The pivot assembly212pivotally couples the hook deployment assembly210and the second linkage assembly250to enable rotation of the hook deployment assembly210relative to the frame230. As described in greater detail below, the arresting hook system102of the illustrated example reacts forces imparted in directions aligned with the roll axis132, a longitudinal axis232, the pivot axis236, and/or the third pivot axis220a. Furthermore, the arresting hook system102reacts moments imparted about a vertical axis234orthogonal to the longitudinal axis232aand the primary pivot axis224a(FIGS.2A-2C). As mentioned, the third pivot axis220ais substantially parallel with the pitch axis136of the aircraft. In some examples, the longitudinal axis232and the vertical axis234are parallel to the roll axis132and the yaw axis134, respectively. However in the illustrated example ofFIG.2D, the longitudinal axis232is not parallel to the roll axis132.

In the illustrated example ofFIG.2D, the trapeze deployment assembly208of the illustrated example reacts forces in directions aligned with the roll axis132and/or the third pivot axis220a. The pivot assembly212of the illustrated example reduces moment forces imparted about the third pivot axis220aand/or moment forces imparted about the vertical axis234. The arresting hook system102is symmetrical about the roll axis132. Additionally, the arresting hook system102of the illustrated example enables a narrow system envelope in the pivot axis236, thereby saving space. Specifically, the arresting hook system102requires the opening260to be relatively narrow between a first side230aof the frame230and a second side230bof the frame230defining the opening260.

FIG.3Ais a perspective view of the trapeze deployment assembly208ofFIGS.2A-2Cshown in the retracted position244.FIG.3Bis a perspective view of the trapeze deployment assembly208ofFIGS.2A-2Cshown in the extended position246. The trapeze deployment assembly208includes a forward body or trapeze plate302, an aft plate or aft body304, a coupling306(e.g., one or more coupling bodies), and the vertical actuator242.

The trapeze plate302includes a trapeze platform308and defines the first joint216and the second joint218opposite the first joint216. The first joint216of the illustrated example includes clevis joints310and the second joint218of the illustrated example includes clevis joints312. The trapeze plate302of the illustrated example is coupled to the primary structure and/or the frame230(FIG.2A) of the aircraft100via the first joint216(e.g., revolute joint, pin joint, hinge joint, etc.). The first joint216includes the first set of pins280(FIG.2D) and bearings or bushings314. The clevis joints310receive the first set of pins280and the bushings314. The first joint216defines the first pivot axis216aoriented substantially parallel relative to the pivot axis236. The first joint216is stationary or fixed relative to the frame230such that the first pivot axis216adoes not translate (e.g., move in a linear direction) relative to the frame230. However, the trapeze plate302is rotatable relative to the frame230about the first pivot axis216a. Specifically, the first set of pins280(e.g., and/or the bearings or bushings314) are disposed within the first joint216of the trapeze plate302to enable rotation of the trapeze plate302relative to the frame230. Additionally, the vertical actuator242of the illustrated example is coupled to the trapeze plate302. For example, the vertical actuator242includes a housing or first cylinder316that houses or receives a first piston318. The first cylinder316defines the first end242aof the vertical actuator242that couples to the frame230and the first piston318defines the second end242bof the vertical actuator242that couples to an inner or upper surface302aof the trapeze plate302. Specifically, the first end242aof the vertical actuator242is coupled (e.g., pivotally coupled) to the frame230via a fitting320(e.g., bearing, bushing, etc.). The second end242bof the first piston318is coupled to the trapeze platform308via a bracket322(e.g., a clevis bracket). As such, the vertical actuator242can be described as an end-mounted double-acting actuator capable of extending and retracting the piston318. Operation of the vertical actuator242causes rotation of the trapeze plate302about the first pivot axis216a, which in turn causes the movement (e.g., rotational and/or translational movement) of the second joint218relative to the frame230. The vertical actuator242of the illustrated example is a hydraulic actuator. However, the vertical actuator242can be a pneumatic actuator, an electric actuator and/or any other actuator(s).

The trapeze plate302is a rigid body. Specifically, the trapeze plate302of the illustrated example is a solid rectangular plate having ribs324(or ridges) (FIG.3B) to provide structural support to the trapeze deployment assembly208. The ribs324are advantageously positioned to redistribute material to areas of the trapeze plate302that are most prone to high stresses and/or fatigue. As such, areas surrounding the ribs324can have reduced (or thinned) material to conserve weight of the trapeze deployment assembly208. In other words, the ribs324enable the trapeze plate302to withstand high tension and torsional loading associated with an arresting event while reducing weight of the trapeze deployment assembly208. The ribs324of the illustrated example include a first rib324aand a second rib324bextending between diagonally opposing corners of the trapeze plate302. As shown, the first rib324aintersects the second rib324badjacent or at a midpoint of the trapeze plate302. In some examples, the trapeze plate302includes additional ribs extending across the trapeze plate302in any desired pattern.

The aft body304defines the third joint220, the fourth joint222and a fifth joint224. The third joint220pivotally couples the aft body304to the frame230of the aircraft100to enable rotational movement of the aft body304about the third pivot axis220a. The fourth joint222couples to the second joint218via the coupling306. The second joint218enables rotational movement of the trapeze plate302relative to the aft body304about the second pivot axis218adefined by the second joint218and/or the fourth pivot axis222adefined by the fourth joint222. The fourth joint222enables rotational movement of the aft body304relative to the trapeze plate302about the fourth pivot axis222adefined by the fourth joint222and/or the second pivot axis218adefined by the second joint218. The fifth joint224pivotally couples to the pivot assembly212(FIG.2A) to pivotally couple the trapeze deployment assembly208and the hook deployment assembly210(FIGS.2A-2C). The fifth joint224enables rotation about the primary pivot axis224a.

In the illustrated example, the aft body304is coupled to the frame230(FIG.2A) (or any other airframe) of the aircraft100via the third joint220. The third joint220includes the second set of pins282. The third joint220pivotally fixes the aft body304to the frame230such that the third joint220allows rotation of the aft body304relative to the frame230about the third pivot axis220a. For example, the aft body304is rotatable about the third pivot axis220avia the second set of pins282(e.g. and/or a combination of pins and bearings or bushings). Similar to the first joint216, the third joint220does not move or translate relative to the frame230. In the illustrated examples, the aft body304is a solid triangular plate or structure defining a triangular or L-shaped profile. Specifically, the aft body304includes a first side plate304a(e.g., a first lateral plate) spaced from a second side plate304b(e.g., a second lateral plate) to define a cavity326therebetween. A plate328couples the first side plate304aand the second side plate304bto form the aft body304. At least a portion of the arresting hook system102nests within the cavity326when the arresting hook system102is in the stowed position202(FIG.2A). The cavity326enables the trapeze deployment assembly208to fold and/or collapse (e.g., above the OML262(FIG.2A)) while the cavity326of the aft body304receives at least a portion of the pivot assembly212(FIG.2A) and/or at least a portion of the hook deployment assembly210(FIG.2A) such that the side plates304aand304bflank or surround the at least the portion of the pivot assembly212and/or the at least the portion of the hook deployment assembly210. As such, the arresting hook system102of the illustrated example occupies a reduced volume when in the stowed position202(FIG.2A) based on the configuration of the cavity326of the aft body304. The fourth joint222of the illustrated example includes clevis joints330. The clevis joints330are oriented toward the clevis joints312of the second joint218.

The coupling306pivotally couples (e.g., links) the trapeze plate302and the aft body304. In the illustrated example, the trapeze plate302is pivotally coupled (or joined) to the coupling306via the second joint218(e.g., revolute joint, pin joint, hinge joint, etc.). The second joint218includes a second set of pins332to pivotally couple the trapeze plate302and a first end306aof the coupling306to enable rotation about the second pivot axis218a. The second joint218is not directly coupled to the frame230and, thus, can translate relative to the frame230as the trapeze plate302rotates about the first joint216(e.g., in response to actuation of the vertical actuator242). The coupling306of the illustrated example include a first link334and a second link336spaced from the first link334in a direction along an orientation parallel to the pivot axis236. For instance, the first link334has a first end (e.g., one of the first ends306a) coupled to a first one of the clevis joints312of the second joint218via a first one of the pins332and the second link336includes a first end coupled to a second one of the clevis joints312via a second one of the pins332. The pins332couple the first link334and the second link336to respective ones of the clevis joints312to enable rotation of the coupling306relative to the trapeze plate302about the second pivot axis218a. However, in some examples, the coupling306can be a unitary body.

The aft body304is coupled to the coupling306via the fourth joint222(e.g., revolute joint, pin joint, hinge joint, etc.). The fourth joint222includes a fourth set of pins338to pivotally couple the aft body304and the second end306bof the coupling306to enable rotation about the fourth pivot axis222a. The fourth joint222is not directly coupled to the frame230and, thus, can translate relative to the frame230as the aft body304rotates about the third joint220(e.g., in response to actuation of the vertical actuator242). For instance, the first link334has a second end coupled to a first one of the clevis joints330of the fourth joint222via a first one of the fourth set of pins338and the second link336includes a second end coupled to a second one of the clevis joints330via a second one of the fourth set of pins338. The pins338couple the first link334and the second link336to respective ones of the clevis joints330to enable rotation of the coupling306relative to the aft body304about the fourth pivot axis222a. The aft body304pivotally couples the hook deployment assembly210and the trapeze deployment assembly208via the pivot assembly212(FIGS.2A-2D). Specifically, the pivot assembly212couples to the fifth joint224of the aft body304. The fifth joint224enables rotation of the hook deployment assembly210about the fifth pivot axis224a. The fifth joint224of the illustrated example is not fixed to the frame230and, thus, moves or translates relative to the frame230when the arresting hook system102moves between the stowed position202(FIG.2A) and the deployed position204(FIG.2B). The aft body304of the illustrated example includes apertures that receive bearings for defining the fifth joint224and the fifth pivot axis224a.

FIG.4is a perspective view of the example hook deployment assembly210of the arrestment hook system102ofFIGS.2A-2C. The hook deployment assembly210of the illustrated example includes a hook shank402, a hook404and the VDA252. The hook shank402of the illustrated example is an elongated body (e.g., a beam) positioned in an orientation perpendicular to the primary pivot axis224a. The hook shank402of the illustrated example includes a first end402aand a second end402bopposite the first end402a. The first end402aof the hook shank402supports the hook404. For example, the hook404of the illustrated example is removably coupled to the first end402avia fasteners405. However, in some examples, the hook404is integrally formed with, or permanently fixed (e.g., via welding) to, the hook shank402as a unitary structure. The hook404of the illustrated example does not move (e.g., rotate or translate) relative to the hook shank402. The second end402bincludes a connector406to couple to the pivot assembly212. The connector406of the illustrated example is a hook shank clevis408(e.g., or a C-shaped connector). The connector406and/or the hook shank clevis408of the illustrated example includes a first plate410spaced from a second plate412to define a cavity408abetween the first plate410and the second plate412to receive the pivot assembly212. The connector406(e.g., the hook shank clevis408) couples to the pivot assembly212, which pivotally couples the hook shank402and the aft body304of the trapeze deployment assembly208. The pivot assembly212enables vertical pivotal movement of the hook shank402relative to the aft body304and/or the frame230(FIG.2A) about the primary pivot axis224adefined by the fifth joint224.

The VDA252of the illustrated example is pivotally coupled to the frame230. For example, the VDA252of the illustrated example is pivotally coupled to the frame230via the sixth joint226to enable rotation of the VDA252relative to the frame230about the sixth pivot axis226a. The VDA252of the illustrated example includes a second piston414slidably disposed within a housing or second cylinder416. Specifically, the second cylinder416of the VDA252of the illustrated example is pivotally coupled to the frame230.

To pivotally couple the VDA252and the frame230about the sixth joint226, the VDA252includes a trunnion418protruding from opposing sides of the second cylinder416. In some examples, the trunnion418fits within and/or is coupled to the frame230via a bushing or bearing such that the VDA252rotates about the sixth pivot axis226a. In the illustrated example, the second cylinder416has a length420. The trunnion418of the illustrated example is positioned approximately at or adjacent to a midpoint of the length420. In some examples, approximately at a midpoint means that the trunnion418is located near or exactly at the midpoint (e.g., precisely or within 10 percent of half of the length420). In some examples, approximately adjacent to the midpoint means that the trunnion418can be located closer to the midpoint of the length420than respective ends of the second cylinder416. However, in some examples, the trunnion418can be positioned at any point along the length420, including ones of the respective ends of the second cylinder416. Thus, positions of the axes220a,224a,226a,228acan be adjusted based on the position of the trunnion418along the length420. The axes218a,222a,224a,226adefine the second linkage assembly250(e.g., second bar linkage, damping four-bar linkage, etc.) and the positioning of the hook404as the aft body304rotates. Furthermore, the positions of the axes218a,222a,224a,226aaffect the motion profile of the arresting hook system102during deployment and the arrestment kinematic arrangement of the arresting hook system102during engagement with the arresting cable. In other words, the deployed position of the hook404and the performance of the arresting hook system102are based on the position of the trunnion418(e.g., along a longitudinal direction of the cylinder416). As such, the position of the trunnion418along the length420can be determined based on desired deployed position(s) and desired performance of the arresting hook system102. Conventional arresting hook systems with non-trunnion mounted dampers have limited hook positions and damping kinematics relative to teachings disclosed herein.

The second piston414is operatively coupled to the hook shank402via the pivot assembly212. Thus, the second cylinder416is pivotally coupled to the frame230via the sixth joint226and the second piston414is coupled to the pivot assembly212. Operation of the VDA252enables movement of the hook shank402and/or the hook404between the non-engagement position254(FIG.2A) and the arrestment position256(FIG.2B) (e.g., in response to the arresting hook system102moving between the stowed position202and the deployed position204). In some examples, the VDA252is a damper actuator. For example, the damper actuator can be similar to a damper actuator of landing gear, landing strut, oleo strut, or the like. Thus, the VDA252can use fluid (e.g., oil, etc.) for velocity dependent resistance (i.e., damping). Furthermore, the VDA252can use gas (e.g., air, nitrogen, etc.) for position dependent resistance (i.e., actuation).

FIG.5Ais a perspective view of the example pivot assembly212of the arresting hook system102ofFIGS.2A-2C. The pivot assembly212of the illustrated example includes a coupler502, a linkage arm504and a pin506. Specifically, the hook shank clevis408is configured to receive the pivot assembly212. Specifically, a cavity408aof the hook shank clevis408is structured to receive the coupler502and the linkage arm504extends from the hook shank clevis408and/or the coupler502. As described in greater detail below, the pivot assembly212restricts or inhibits translational movement of the hook404and/or the hook shank402in a lateral direction along the primary pivot axis224aand/or rotational movement of the hook404and/or the hook shank402about the vertical axis234. Specifically, the coupler502couples to the hook shank402and the trapeze deployment assembly208(FIG.2A). The linkage arm504operatively couples the VDA252(FIG.4) and the hook deployment assembly210. The coupler502and the pin506define the fifth joint224when the coupler502and the pin506couple to the aft body304via the apertures340and the bearings342(FIG.3B).

FIG.5Bis a perspective view of the coupler502ofFIG.5A. The coupler502of the illustrated example has a body508(e.g., a cylindrical body). The body508of the illustrated example includes a first opening510(e.g., a vertical opening or through hole) and a second opening512(e.g., a horizontal or transverse bore). The first opening510is transverse relative to the second opening512. Specifically, the first opening510defines a first axis514and the second opening512defines a second axis516. The first axis514is transverse relative to the second axis516. In the illustrated example, the first axis514intersects the second axis516. Specifically, the first axis514is non-parallel relative to the second axis516. In the illustrated example, the first axis514is substantially perpendicular relative to the second axis516. In some examples, substantially perpendicular means perfectly perpendicular (e.g., the first axis514and the second axis516have a 90 degree relationship) or the first axis514is within 10 degrees of perfectly perpendicular relative to the second axis516.

In some examples, the first axis514corresponds to the vertical axis234and the second axis516corresponds to the primary pivot axis224a. In other examples, the first opening510extends in a direction parallel to the lateral axis234aand the second opening512extends in a direction parallel to the primary pivot axis224a. In other words, the first axis514is parallel to the lateral axis234a(e.g., a vertical axis in the orientation ofFIG.5B) and the second axis516is parallel relative to the primary pivot axis224aand/or the pivot axis236(e.g., a lateral axis in the orientation ofFIG.5B). The first opening510has a first dimension (e.g., a first diameter) and the second opening512has a second dimension (e.g., a second diameter). In the illustrated example, the first dimension is greater than the second dimension. However, in some examples, the first dimension is equal to or smaller than the second dimension.

The body508includes a first boss518and a second boss520opposite the first boss518. The first boss518and the second boss520extend from an outer surface522of the body508in opposite directions along the second axis516. The coupler502includes a cam524that protrudes from the outer surface522. Specifically, the cam524extends from the outer surface522along the longitudinal axis232a(FIG.2D) in a direction (e.g., a longitudinal direction) rearward of the coupler502and/or the aircraft100when the coupler502is coupled to the aircraft100. The cam524includes a first arm526and a second arm528. In the illustrated example, the cam524is a lateral damping cam to engage with a lateral damper inside of the hook shank402(FIG.4), as described further below in connection withFIG.5E.

FIG.5Cis a perspective, side view of the linkage arm504ofFIGS.2A-2C and5A. The linkage arm504of the illustrated example includes a shaft530and an arm532extending from the shaft530. For example, the linkage arm504has an L-shaped profile. The shaft530includes apertures534defining a third opening536(e.g., a through hole or transverse bore) having a third axis538. The third axis538of the illustrated example is parallel relative to the second axis516. In the illustrated example, the second opening512of the coupler502and the third opening536of the linkage arm504coaxially align when the linkage arm504is coupled to the coupler502. The arm532extends from the shaft530in a rearward direction or in a direction along the longitudinal axis232a(FIG.2D) toward the hook404(FIG.4). An end532aof the arm532opposite the shaft530receives the second piston414and provides the seventh joint228. Specifically, the end532aof the arm532includes a connector540to couple to or receive the second piston414of the VDA252. Specifically, the connector540of the illustrated example is a clevis connector (e.g., a link arm clevis). However, in other examples, the connector540can be a plate, a slot, and/or any other connector540to couple to a rod end of the second piston414. The connector540of the illustrated example includes lateral plates540aand540bhaving apertures542defining a fourth opening544defining the seventh pivot axis228a. The seventh pivot axis228aenables pivotal rotation between the second piston414of the VDA252and the arm532of the pivot assembly212. The seventh pivot axis228ais spaced from the first axis514a distance548in the orientation of the longitudinal axis232a(FIG.2D). The distance548is based on a length of the arm532. For example, the distance548is substantially equal to the length of the arm532. The shaft530of the illustrated example has a shaft diameter. The shaft diameter of the illustrated example is less than the first diameter of the first opening510of the coupler502.

FIG.5Dis a perspective view of the coupler502and the pin506of the pivot assembly212ofFIGS.2A-2C and5A. The linkage arm504is not shown inFIG.5Dfor clarity.FIG.5Eis a perspective, cutaway view of the pivot assembly212ofFIGS.2A-2C and5A.FIG.5Fis a cross-sectional view of the pivot assembly212ofFIGS.2A-2C and5Ataken along the pivot axis236. As noted above, the hook shank402includes a cavity549within the second end402b. In the illustrated example, a lateral damper550is disposed in the cavity549. The cam524engages the lateral damper550to oppose lateral displacement and dynamic motion of the hook shank402. Thus, the lateral damper550can provide a centering force to the hook shank402via the cam524and the pivot assembly212.

The pin506of the illustrated example couples or fixes the coupler502and the linkage arm504. Specifically, the shaft530of the linkage arm504is positioned in the first opening510of the coupler502such that the second opening512of the coupler502aligns (e.g., coaxially aligns) with the third opening536of the shaft530of the linkage arm504. To couple the coupler502and the linkage arm504, the pin506extends through the second opening512of the coupler502and the third opening536of the linkage arm504. The pin506of the illustrated example is a cylindrical body having fasteners551(e.g., bolts or retainers) at respective ends of the pin506to clamp or engage the respective side plates304aand304bof the aft body304(seeFIG.3A). The fasteners551engage respective outer surfaces of the aft body304. When the pivot assembly212is assembled, the pin506retains and/or couples the coupler502and the linkage arm504with the hook shank402to inhibit and/or restrict lateral and/or rotational movement between the hook shank402and the pivot assembly212about the longitudinal axis232, the vertical axis234and/or the primary pivot axis224a. Additionally, the pin506, the second opening512of the coupler502and the third opening536of the linkage arm504define the primary pivot axis224a(FIG.2A). The VDA252couples to the pivot assembly212via the seventh joint228.

Thus, the pivot assembly212is structured to cause the primary pivot axis224a(e.g., an axis in the pivot axis236orientation) of the trapeze deployment assembly208to intersect a vertical axis552of the linkage arm504(e.g., an axis in the vertical axis234orientation) of the hook deployment assembly210when the pivot assembly212pivotally couples the trapeze deployment assembly208and the hook deployment assembly210. As a result, the intersection of the primary pivot axis224aand the vertical axis552is to at least one of reduce or eliminate a lateral bending moment into the trapeze deployment assembly208, thereby enabling use of a smaller trapeze deployment assembly208and reduce aircraft weight to improve efficiency and/or reduce costs.

FIG.6Ais a partial side view of the example arresting hook system102ofFIGS.2A-2Cshown in the stowed position202.FIG.6Bis a partial side view of the example arresting hook system102ofFIGS.2A-2Cshown in the deployed position204.FIG.6Cis a partial side view of the example arresting hook system102ofFIGS.2A-2Cshown in the inspection position206. Referring toFIGS.6A-6C, the first linkage assembly240of the illustrated example defines a first bar linkage602and the second linkage assembly250of the illustrated example defines a second bar linkage604, schematically shown inFIGS.6A-6Cby solid and dashed lines. The first bar linkage602is operatively coupled to the second bar linkage604.

The first bar linkage602of the illustrated example includes a first forward link606, a first coupler link608, a first aft link610, and a first ground link612. The first forward link606is between the first joint216and the second joint218of the trapeze platform308. The first coupler link608of the illustrated example is between the second joint218of the trapeze platform308and the fourth joint222of the aft body304. The first aft link610of the illustrated example is between the fourth joint222of the aft body304and the fifth joint224of the aft body304. The first ground link612(dashed line) of the illustrated example is between the third joint220of the aft body304and the first joint216of the trapeze platform308. More specifically, the first forward link606extends between the first pivot axis216aand the second pivot axis218a. The first coupler link608extends between the second pivot axis218aand the fourth pivot axis222a. The first aft link610extends between the fourth pivot axis222aand the third pivot axis220a. In some examples, the first forward link606can be referred to as a driving link of the trapeze deployment assembly208because the actuation of the vertical actuator242and the rotation of the first forward link606causes actuation of other links of the first bar linkage602.

The second bar linkage604of the illustrated example includes a second forward link614, a second coupler link616, a second aft link618, a second ground link620. The second forward link614of the illustrated example is between the third joint220and the fifth joint224of the aft body304. The second coupler link616of the illustrated example is between the fifth joint224and the seventh joint228of the linkage arm504. In some examples, the second forward link614can be referred to as the driving link of the second bar linkage604. The second aft link618of the illustrated example is between the seventh joint228and the sixth joint226of the second cylinder416of the VDA252(e.g., a pivot joint of the VDA252). Thus, VDA252(e.g., the second cylinder416and the second piston414) defines the second aft link618. The second ground link620(dashed lines) of the illustrated example is between the third joint220of the aft body304and the sixth joint226of the second cylinder416. More specifically, the second forward link614of the illustrated example is between the third pivot axis220aand the primary pivot axis224a. The second coupler link616of the illustrated example is between the primary pivot axis224aand the seventh pivot axis228a. The second aft link618of the illustrated example is between the seventh pivot axis228aand the sixth pivot axis226a. The second ground link620of the illustrated example is between the sixth pivot axis226aand the third pivot axis220a.

It should be appreciated that a length of the second aft link618can be adjusted based on a position of the second piston414within the second cylinder416. Thus, as described further below, the damping kinematics of the second bar linkage604can change based on the length of the second aft link618. In some examples, the second bar linkage604ofFIG.6Bcan be considered to be a different linkage than the second bar linkage604ofFIG.6Cbecause of the different lengths of the second aft link618. However, the second aft link618ofFIG.6Bincludes the same components (e.g., the second piston414, the second cylinder416, etc.) as the second aft link ofFIG.6C.

Because of the triangular configuration and rigid structure of the aft body304, the first aft link610and the second forward link614are fixed together at the third joint220. That is, the first aft link610and the second forward link614are rotatably interlocked with the aft body304. Thus, as the aft body304rotates about the third pivot axis220a, the first aft link610and the second forward link614also rotate about the third pivot axis220a. Additionally, the third joint220is fixed to the fourth joint222and the fifth joint224. Thus, rotation of the aft body304about the third pivot axis220acauses movement (rotational and/or translational movement) of the fourth joint222and the fifth joint224. In other words, the first aft link610and the second forward link614are rotatably interlocked via the aft body304.

The combination of the first bar linkage602and the second bar linkage604can referred to herein as a linkage assembly622having a seven-bar or eight-bar linkage assembly. In the arresting hook system102disclosed herein, the linkage assembly622is achievable based on the trunnion-mounted manner in which the VDA252is coupled the frame230. Because the first aft link610and the second forward link614are both defined by the aft body304, the first aft link610and the second forward link614can be considered shared or coordinated links that are rotatably interlocked (e.g., rotate simultaneously about the third joint220) and can be considered a single link of a seven-bar linkage assembly.

In the illustrated example, a physical body or link is not included to define the first ground link612and/or the second ground link620. Rather, it should be appreciated that because the first joint216and the third joint220are fixed or coupled to the frame230of the aircraft100, the first ground link612is formed therebetween. Likewise, it should be appreciated that because the third joint220and the sixth joint226are fixed or coupled to the frame230of the aircraft100, the second ground link620is formed therebetween. In some examples, the linkage assembly622includes a physical ground bar or link for the first ground link612and/or the second ground link620.

Referring toFIG.6A, when the arresting hook system102is in the stowed position202, the trapeze deployment assembly208provides a compact configuration or envelope. The arresting hook system102is capable of achieving this compact configuration due to the linkage assembly622. For instance, the compact configuration can be provided because the trapeze deployment assembly208folds into the cavity326(FIG.3B) of the aft body304, which receives the pivot assembly212. For example, the pivot assembly212and/or portions of the hook shank402(e.g., the hook shank clevis408) nest within the cavity326of the aft body304when the arresting hook system102is in the stowed position202. Additionally, the VDA252rotates about the sixth pivot axis226ato an initial rotatable position or stored position624. In the stored position624, the second coupler link616substantially aligns (e.g., is substantially parallel) with the second aft link618. Additionally, the third joint220is further aft of the seventh joint228and the fifth joint224. For instance, the third joint220is positioned between the seventh joint228and the sixth joint226. Also, the seventh joint228is positioned between the third joint220and the fifth joint224. In the stowed position202, the arresting hook system102is entirely within or above the OML262(e.g., within the fuselage104).

Referring toFIG.6B, the trapeze deployment assembly208is in an “over-center” position626when the arresting hook system102is in the deployed position204(e.g., the first actuator218has fully actuated, when the trapeze deployment assembly208is in the extended position246). As used herein, the over-center position626refers to a position of the trapeze deployment assembly208when the trapeze plate302is aligned (e.g., colinear) with the coupling306. In other words, the over-center position626refers to a position of the trapeze deployment assembly208when the first forward link606is colinear or substantially parallel with the first coupler link608. The over-center position626allows the trapeze plate302(e.g., the first forward link606), the coupling306(e.g., the first coupler link608), the aft body304, and the first ground link612to function as a triangular structural arrangement. Such a triangular arrangement includes a first side defined between the first pivot axis216aand the primary pivot axis224a, a second side defined between the primary pivot axis224aand the third pivot axis220a, and a third side defined between the third pivot axis220aand the first pivot axis216a. As such, when in the over-center position626, the trapeze deployment assembly208is capable of carrying and/or transmitting loads (e.g., tensile, compressive, bending, etc.) from the hook shank402to the frame230(or another primary structure) of the aircraft100.

Additionally, in known arresting hook systems, the pivot assembly (e.g., Y-frame structure, stringer style, etc.) and/or the hook shank can rotate downward for deployment without any trapezing, unfolding, translating, and/or extending motions during deployment. By contrast, the trapeze deployment assembly208of the arresting hook system102of the illustrated example rotates downward and unfolds and/or extends in a rearward direction (e.g., toward the aft of the aircraft100along the roll axis132ofFIG.2Aand/or the longitudinal axis232aofFIG.2D). It should be appreciated that the performance of the arresting hook system102is at least partially based on how far in the rearward direction the hook404is located when the arresting hook system102is in the deployed position204. The cable capture rate (e.g., likelihood of successful arrestment) of the aircraft100is affected by the rearward distance of the hook404relative to the rear landing gear110. Thus, the performance of the arresting hook system102improves the farther aft the hook404moves during deployment.

As the trapeze deployment assembly208of the illustrated example moves to the extended position246(e.g., lowers), the hook shank402and the pivot assembly212move aft (e.g., in the rearward direction) during deployment due to the configuration of the trapeze deployment assembly208. As such, the hook404of the illustrated example, when in a stowed or the non-engagement position254, is forward (e.g., in the roll axis132orientation) when compared to a stowed position (or non-engagement position) of a hook of known arresting hook systems. Additionally, the hook404of the illustrated example, when in the deployed or arrestment position256, is located aft (e.g., in the roll axis132orientation) when compared to a deployed or arresting position of a hook of known arresting hook systems. Thus, the trapeze deployment assembly208enables the arresting hook system102of the illustrated example to have an increased longitudinal distance (e.g., in the roll axis132orientation) between the stowed position202of the hook404and the deployed position204of the hook404, which improves the performance (e.g., cable capture rate) of the arresting hook system102and conserves space for other onboard systems or sub-systems.

When the hook404of the illustrated example is in the arrestment position256(FIG.2B) and engages an arresting cable during landing, tensile loading on the hook shank402transfers to the trapeze deployment assembly208via the pivot assembly212, and a magnitude of the tensile loading acts aft and away from the trapeze deployment assembly208. Due to the over-center position626the trapeze plate302and the coupling306, the trapeze deployment assembly208can efficiently transfer loading to the frame230. Additionally, the angle of the applied arrestment load is substantially parallel (e.g., within +/−15 degrees) to the on-center alignment of the trapeze plate302(e.g., the first forward link606) and the coupling306(e.g., the first coupler link608). Thus, a first portion of the arrestment load is applied to the trapeze plate302and the coupling306, and a second portion of the arrestment load is applied to the aft body304. In some examples, the first portion can be greater than the second portion. The aft body304provides a stabilizing force to react loads on the hook shank402that are non-parallel to the trapeze plate302and the coupling306(e.g., the on-center alignment). Furthermore, the aft body304provides a shear reaction against a reaction force632(e.g., damping force) of the VDA252. However, known arresting hook systems with a trapezing interface include the VDA coupled directly to (e.g., riding on) a trapeze such that the trapeze bears some of the compressive loading, which may be unfavorable from a performance and/or structural standpoint.

Mounting the VDA252via the trunnion418is advantageous over known manners for mounting the hook shank damper actuator, which typically include mounting an end of a cylinder (e.g., the second cylinder416) to the frame230via a bushing similar to the vertical actuator242. The VDA252of the illustrated example is mounted via the trunnion418to support the cylinder416from buckling due to arrestment loads (e.g., compressive loads, etc.). Thus, the VDA252can support higher loads based on the trunnion418and position of the VDA pivot axis226a. Additionally, the VDA252of the illustrated example provides a strut for the hook shank402via the connection between the second piston414and the linkage arm504of the pivot assembly212(e.g., the seventh joint228) as the hook404(FIG.4) touches a ground landing surface and engages the arresting cable (or pendant). Thus, the VDA252counteracts vertical forces to restrict or inhibit the hook404from bouncing off of a ground landing surface and over the arresting cable. Furthermore, the VDA252reacts the inertia of the hook shank402associated with the rapid pivot of the hook shank402due to the engagement. As such, the VDA252inhibits or prevents “up-strike” of the hook shank402against (e.g., into) the fuselage104(FIG.1). In some examples, the VDA252rotates about the sixth pivot axis226atoward aft body304when the hook shank402rotates rearward (e.g., toward the aft of the aircraft100).

The trunnion418of the VDA252enables the second bar linkage604to support (e.g., react vertical arrestment loads) the hook shank402. For example, mounting the VDA252to the frame230via the trunnion418enables more effective transmission angles that result in favorable damping kinematics. As used herein, a “transmission angle” is a transmission angle628between the second aft link618and the second coupler link616. When the arresting loads are applied to the hook shank402, an arresting load630is applied to the second coupler link616at the seventh joint228. The second aft link618counteracts this arresting load with the reaction force632acting along the second aft link618toward the seventh joint228. Thus, the second aft link618and the second coupler link616define the transmission angle628of the second bar linkage604. In known arresting hook systems, the damper actuator(s) (e.g., the VDA252) is mounted on and/or coupled to a trapeze deployment assembly. Although such a configuration can eliminate coordination between trapeze actuation and hook shank actuation, it can also require a significant stroke length (e.g., or piston length) to fully deploy a hook shank, which increases the size and/or weight of an arresting hook system.

It should be appreciated that the moment force imparted to the hook deployment assembly210is increased (e.g., maximized) when the transmission angle628is at approximately ninety degrees. Furthermore, a damping force the VDA252can output is based on the air spring pre-charge and the tuning of an internal relief valve. The amount of rotational energy the arresting hook system102is able to remove (i.e., damping kinematics) is based on the damping force, the transmission angle628at full extension, and the transmission angle628at full up-swing. As such, the damping kinematics of the arresting hook system102are adjustable based on the location of the trunnion418and the value of the resulting transmission angle628. In the illustrated examples, as the hook shank402rotates upward during arrestment, the transmission angle628progressively increases. In some examples, the transmission angle628is ninety degrees after the hook shank404has reached the midpoint of upward rotation/travel. Thus, the arresting hook system102provides improved damping kinematics along the majority of the upward rotation of the hook shank402during arrestment. In some examples, the transmission angle628is approximately 45 degrees when the arresting hook system102is in the deployed position204. In some examples, the transmission angle628is approximately 120 degrees when the arresting hook system102is in the inspection position206.

Because known arresting hook systems couple a hook shank damper actuator (e.g., the VDA252) directly to a trapezing structure, a transmission angle formed between the actuator and the hook shank at the end of the piston stroke is relatively small (e.g., approximately between 10 degrees and 30 degrees). In some other known systems, a piston stroke length of the hook shank damper actuator is significantly increased to make up for the penalty of the small transmission angle, which can increase the complexity, height, volume, weight, and/or up-strike potential of the arresting hook system. Furthermore, the small transmission angle of known systems at an end of stroke length position can cause greater pressures in the hook shank damper actuator due to a high hold-down force coupled with a poor moment arm at end of stroke.

In contrast to known systems, the transmission angle628of the arresting hook system102has more favorable damping kinematics. As such, the arresting hook system102can better maintain the arrestment position256(e.g., a “hook down” position) when the hook404touches the ground, which significantly increases performance characteristic(s) (e.g., a cable capture rate) of the arresting hook system102. Furthermore, the increased transmission angle628enables smaller stroke length of the second piston414and improves efficiency of the VDA252by increasing an amount of energy absorbed, reducing (e.g., minimize) up-swing occurrence, reducing pressure spikes, and/or preventing or reducing up-strike occurrences.

Additionally, operatively coupling or directly decoupling the seventh joint228and/or the sixth joint226from the trapeze deployment assembly208allows for greater design flexibility of the arresting hook system102. For example, when different kinematics of an arresting hook system are needed, a position of the VDA252can be adjusted without moving or changing a position of the seventh joint228(e.g., without changing a length of the linkage arm504). Thus, the arresting hook system102does not need to be significantly redesigned when implemented in a different aircraft, when different performance is needed during a product development cycle, etc. In some examples, the configuration of the linkage assembly622(and, in particular, the second bar linkage604) enables design flexibility for the arresting hook system102, such that minimal changes to a configuration (e.g., a diameter of the second piston414) or a position of the VDA252relative to the seventh joint228to adjust the performance (e.g., damping kinematics) of the arresting hook system102.

Referring to6C, the first end242aof the vertical actuator242is mounted on or coupled to the frame230via a bearing634such that the first joint216is positioned at a first distance636from the OML262. The third joint220of the aft body304is coupled to the frame230such that the third joint220is positioned at a second distance638from the OML262. In some examples, the second distance638is different than (e.g., greater than) the first distance636. However, in some other examples, the second distance638can be equal to, or less than, the first distance636. The first distance636and/or the second distance638cause at least a portion of the trapeze deployment assembly208to be disposed below the OML262when the arresting hook system102is in the inspection position206ofFIGS.2C and6Cand/or the deployed position204ofFIGS.2B and6B. More specifically, when the trapeze deployment assembly208is in the extended position246(e.g., is unfurled), the fifth joint224is positioned below the OML262. In the illustrated example, the second joint218, the fourth joint222, the fifth joint224and the seventh joint228are positioned below the OML262when the trapeze deployment assembly208is in the extended position246. Furthermore, reducing the first distance636and/or the second distance638relative to the OML262substantially improves the lateral loading capability of the trapeze deployment assembly208. The hook shank402can impart lateral loads on the fifth joint224when the hook404engages the arresting cable at an off-center angle. For example, a crosswind may cause the aircraft100to be askew relative to a landing strip during landing, which can cause lateral loading or side loading to act on the hook shank402. Such lateral loading acts as a moment force on the arresting hook system102, which can in turn cause bending in the associated components thereof. Because the first distance636and the second distance638are relatively close to the OML262, components of the trapeze deployment assembly208(e.g., the trapeze plate302, the aft body304, etc.) can be fabricated with shorter or truncated lengths (e.g., in a longitudinal or the roll axis132direction), which can improve the bending strength of the trapeze deployment assembly208.

Moreover, it should be appreciated that extending the hook404further below the OML262improves engagement performance between the arresting hook system102and the arresting cable. Thus, by providing shorter distances between the first distance636and the OML262and/or the second distance638and the OML262enables positioning the hook404to a lower position below the OML262, which can improve performance characteristics (e.g., cable capture rate) of the arresting hook system102. In other words, the vertical positions of the first joint216and/or the third joint220provided by the first distance636and the second distance638, respectively, relative to the OML262reduce the chances for the hook404to up-swing into the OML262.

FIG.7Ais a partial, side view of the locking assembly214with arresting hook system102ofFIGS.2A-2Cin the stowed position202.FIG.7Bis a perspective, partial view of the hook deployment assembly210ofFIGS.2A-2C.FIG.7Cis a partial, perspective side view of the locking assembly214with the arresting hook system102ofFIGS.2A-2Cin the inspection position206.

The locking assembly214of the illustrated example is coupled to the frame230of the aircraft100(e.g., via one or more brackets). In the illustrated example, the locking assembly214is located towards an aft region of the arresting hook system102. Specifically, the locking assembly214of the illustrated example includes a dual lock700. Specifically, the locking assembly214includes a first lock or passive lock702and a second lock or directional lock704(or bypass lock). The passive lock702is oriented toward the directional lock704. Specifically, the passive lock702and the directional lock704are positioned in a travel path706of the hook404. The passive lock702of the illustrated example includes a capture hook or pocket708(e.g., oriented toward the directional lock704). The locking assembly214of the illustrated example includes a track710defining a length712between a first end710aand a second end710bopposite the first end710a. The first end710aof the track710includes the passive lock702and the second end710bincludes the directional lock704. The passive lock702of the illustrated example is a hook-shaped end (e.g., a C-shaped end, a capture hook, etc.) formed at the first end710aof the track710. The passive lock702is formed by a portion714aof the track that curls and wraps toward the directional lock704and/or the track710.

The directional lock704includes a latch716and a selector718. The latch716(e.g., a spring-loaded latch) and the selector718are each pivotally coupled to rotate relative to the frame230. The latch716is coupled to rotate relative to the frame230about a first latch joint720defining a first latch pivot axis720aand a second latch joint722defining a second latch pivot axis722a, different than the first latch joint720and/or the first latch pivot axis720a. A spring724is coupled to the latch716and the track710. Specifically, the spring724has a first end fixed to an anchor725coupled to the track710and a second end opposite the first end coupled to the first latch joint720. A stop726is coupled or formed with the track710to prevent further rotation of the latch716in a first rotational direction728(e.g., a counterclockwise direction in the orientation ofFIG.7A) opposite a second rotational direction730(e.g., a clockwise direction in the orientation ofFIG.7A) when the latch716is in engagement with the stop726as shown inFIG.7A. The selector718is coupled to the track710via a selector joint732. The selector joint732defines a selector pivot axis732aabout which the selector718rotates relative to the frame230and/or the track710(e.g., in the first rotational direction728and/or the second rotational direction730). The selector718is positioned forward of the of the latch716in the orientation of the roll axis132. The selector pivot axis732ais different and/or spaced from the first latch pivot axis720aand the second latch pivot axis722ain the orientation of to the roll axis132and/or the yaw axis134. The selector718of the illustrated example includes a spring hinge736(e.g., a torsion spring) to bias the selector718toward the latch716. The first latch joint720, the second latch joint722and the selector joint732of the illustrated example are formed by one or more pins, bushings, bearings, etc.

In the examples ofFIGS.7B and7C, the locking assembly214of the illustrated example includes a guide738. Specifically, the guide738of the illustrated example is coupled to the hook shank402adjacent to the hook404. The guide738moves along the track710with the hook shank402when the arresting hook system102moves between the stowed position202and the deployed position204. Specifically, the guide738interacts with the passive lock702when the arresting hook system102is in the stowed position202and the directional lock704when the arresting hook system102is in the inspection position206. Additionally, the directional lock704enables the guide738to bypass the directional lock704during a deployment event when the arresting hook system102moves from the stowed position202to the deployed position204. The guide738of the illustrated example includes a roller740and a bracket742. The guide738(e.g., the roller740) is coupled to the hook shank402via the bracket742(e.g., an upper surface744of the hook shank402in the orientation ofFIG.7B). The bracket742of the illustrated example includes a first bracket plate742aand a second bracket plate742bspaced from the first bracket plate742asuch that the roller740is positioned therebetween. The roller740is axially coupled to the bracket742and can roll relative to the bracket742about a roll axis746when the roller740engages (e.g., rolls) with the track710(e.g., between the passive lock702and the directional lock704). When the selector718is positioned against the latch716as shown inFIGS.7A and7C, the selector718and the latch716define a capture chamber748. The capture chamber748receives the guide738(e.g., the roller740) when the arresting hook system102is in the inspection position206(FIG.7C).

FIGS.8A-18illustrate the example arresting hook system102at different operational positions. The arresting hook system102may be actuated to the deployed position204when the aircraft100approaching a runway. In operation, as described in greater detail in connection withFIGS.8A-18, operation of the vertical actuator242and the VDA252cause the arresting hook system102to move between the stowed position202and the deployed position204. For example, to deploy the hook404, the vertical actuator242is actuated to move the trapeze deployment assembly208between the retracted position244and the extended position246(e.g., the over-center position626) and the VDA252is actuated to move the hook deployment assembly210between the non-engagement position254(FIG.2A) and the arrestment position256(FIG.2B). For example, the vertical actuator242causes the hook404to move along the roll axis132(e.g., in a generally horizontal direction) between the passive lock and the bypass lock. The VDA252causes the hook404to move along the yaw axis134(e.g., in a generally vertical direction) between the directional lock704and the ground surface112(FIG.1). In the illustrated example, the vertical actuator242is actuated prior to actuation of the VDA252. In other words, the vertical actuator242is actuated first, and then the VDA252is actuated. However, in some examples, the vertical actuator242and the VDA252can be actuated simultaneously. In some examples, the VDA252can be actuated during actuation of the vertical actuator242.

FIG.8Ais a side view of the arresting hook system102shown in the stowed position202.FIG.8Bis a cross-sectional view ofFIG.8A. In the stowed position202, the vertical actuator242(e.g., the first piston318) is in a first retracted position802and the VDA252(e.g., the second piston414) is in a second retracted position804. When the vertical actuator242is in the first retracted position802, the trapeze deployment assembly208is positioned in the retracted position244. Additionally, in the stowed position202, the VDA252is in a second retracted position804. Furthermore, the second cylinder416is in a first rotational position806. When the VDA252is in the second retracted position804and the second cylinder416is in the second rotational position806, the hook deployment assembly210is in a stowed captured position808. Specifically, the trapeze deployment assembly208and the hook deployment assembly210are located within the fuselage104or above the lower OML262. Furthermore, the guide738is engaged with, or captured by, the passive lock702(e.g., the roller740is positioned in the pocket708). Thus, the passive lock702of the locking assembly214captures the guide738(e.g., the roller740) to retain or support (e.g., a weight of) the hook404. The guide738is spaced away from the directional lock704(e.g., the guide738is not engaged with the directional lock704) and the directional lock704is in an initial position810. Although not shown, the arresting hook system102of the illustrated example includes a primary lock (e.g., a primary lock1902ofFIG.19) that interacts or couples to the aft body304. Additionally, the cover264is in the closed position278. In the stowed position202, the pivot assembly212is in an initial position or nesting position812. In the nesting position812, the pivot assembly212is at a forward most position along the roll axis132(e.g., a horizontal position in the orientation ofFIG.8A). Stated differently, in the stowed position202, the pivot assembly212is closer to the vertical actuator242in a direction along the roll axis132compared to a distance between the vertical actuator242and the pivot assembly212when the arrestment hook system102is in the deployed position.

FIG.9Ais a side view of the arresting hook system102shown in a first intermediate position900.FIG.9Bis a partially, enlarged view of the arrestment hook system102ofFIG.9A. Specifically,FIGS.9A and9Bshow the arrestment hook system102moving in a direction from the stowed position202toward the deployed position204. In the illustrated example, the vertical actuator242(e.g., the first piston318) is in a partially extended position902and the VDA252is in the second retracted position804. With the first piston318in the partially extended position902, the trapeze deployment assembly208is between the retracted position244and the extended position246. As the first piston318moves from the first retracted position802ofFIG.8Ato the partially extended position902, the first piston318imparts a force904on the trapeze plate302causing the trapeze plate302to rotate in the second rotational direction730about the first pivot axis216a, which causes the aft body304to rotate in the first rotational direction728about the third pivot axis220avia the coupling306. In turn, the aft body304causes the pivot assembly212to move (e.g., vertically) below the OML262. Specifically, the first bar linkage602(FIG.6A) and/or the second bar linkage604(FIG.6A) causes the pivot assembly212to extend outside or below the OML262.

Additionally, in response to movement of the trapeze deployment assembly208via actuation of the vertical actuator242from the first retracted position802toward the partially extended position902, the pivot assembly212moves in an aft direction along the roll axis132(e.g., away from the vertical actuator242and toward the locking assembly214), thereby causing the hook shank402to move in an aft direction along the roll axis132. In other words, rotation of the aft body304in the first rotational direction728about the third pivot axis220acauses the pivot assembly212to away from the vertical actuator242along the roll axis132and rotation of the aft body304in the second rotational direction730about the third pivot axis220acauses the pivot assembly212to move toward the vertical actuator242along the roll axis132. As a result, rotation of the aft body304in the first rotational direction728about the third pivot axis220acauses the pivot assembly212to impart a force906against the hook shank402, which causes the hook404to disengage with the passive lock702and move toward the directional lock704. For example, the guide738(e.g., the roller740) disengages or exits the pocket708and rolls against a surface908of the track710from the passive lock702toward the directional lock704.

Although the VDA252of the illustrated example ofFIG.9Ais in the second retracted position804(e.g., fully retracted position), the hook deployment assembly210moves relative to the frame230via the trapeze deployment assembly208. To enable movement of the hook deployment assembly210relative to the frame230when the second piston414is in the second retracted position804, the second cylinder416rotates relative to the frame230about the sixth pivot axis226avia the trunnion418to a second rotational position910. In particular, the second cylinder416rotates in the first rotational direction728about the sixth pivot axis226aand second piston414rotates in the first rotational direction728about the seventh pivot axis228a.

Furthermore, rotation of the aft body304in the first rotational direction728about the third pivot axis220acauses the cover264to move from the cover closed position278(FIG.8A) toward the cover open position279(FIG.2B). For example, the aft body304causes the rod274to impart a force912to the second end266bof the first panel266to cause the first end266aof the first panel266to rotate about the hinge270in the second rotational direction730. The second panel268moves in response to movement of the hook deployment assembly210. Specifically, the first panel266and the second panel268move between the cover closed position278and the cover open position279in response to rotation of aft body304about the third pivot axis220a.

FIG.10Ais a side view of the arresting hook system102shown in a bypass position1000.FIG.10Bis a partially, enlarged view of the arrestment hook system102ofFIG.10A. Specifically,FIGS.10A and10Bshow the arresting hook system102in the bypass position1000along a deployment path in which the arresting hook system102moves from the stowed position202(FIG.2A) toward the deployed position204(FIG.2B). In the illustrated example, the vertical actuator242is a first fully extended position1002(e.g., an end of stroke extended position) and the VDA252is in the second retracted position804(e.g., an end of stroke retracted position). In other words, the VDA252has not yet been activated when the arresting hook system102is in the bypass position1000ofFIGS.10A and10B. Additionally, the pivot assembly212is in a fully extended position1003. In the fully extended position1003, pivot assembly212is farther aft along the roll axis132compared to the nesting position812(FIG.8A). In the illustrated example, the trapeze deployment assembly208is in the extended position246(e.g., a fully extended position) and the trapeze deployment assembly208cannot move the pivot assembly212and/or the hook deployment assembly210further in the aft direction along the roll axis132.

To enable the hook deployment assembly210to move aft along the roll axis132while the VDA252is in the second retracted position804, the second cylinder416rotates about the sixth pivot axis226a(e.g., via the trunnion418) to a third rotational position1004. In particular, the second cylinder416rotates about the sixth pivot axis226ain the first rotational direction728and the second piston414rotates relative to the frame230in the first rotational direction728about the seventh pivot axis228aas the aft body304rotates about the third pivot axis220ato position the second cylinder416in the third rotational position1004and enable the trapeze deployment assembly208to move to the extended position246. Although the second cylinder416rotates from the first rotational position806ofFIG.8A, the second rotational position910ofFIG.9A, to the third rotational position1004ofFIG.10A, the second piston414is in the second retracted position804(FIG.8A). In other words, the second piston414is not actuated prior to the first piston318reaching the first fully extended position1002.

With the vertical actuator242in the first fully extended position1002, the trapeze deployment assembly208is unfolded to the extended position246. In other words, the pivot assembly212is in the over-center position626. In response to moving from the retracted position244to the extended position246, the trapeze deployment assembly208causes the hook shank402and, thus, the hook404of the hook deployment assembly210to move into engagement with the directional lock704along the roll axis132. As the arrestment hook system102moves to the bypass position1000, the guide738engages the directional lock704. In particular, referring toFIG.10B, the guide738(e.g., the roller740) of the illustrated example engages a front surface1006of the selector718and causes the selector718to rotate in the first rotational direction728about the selector pivot axis732a. The selector718pivots about the selector pivot axis732ainto engagement with the latch716, thereby causing the latch716to rotate in the second rotational direction730about the first latch pivot axis720aprovided by the first latch joint720and the second latch pivot axis722aprovided by the second latch joint722. Specifically, the latch716pivots in the second rotational direction730about the first latch pivot axis720aand the second latch pivot axis722ain response to the guide738engaging the selector718and rotating the selector718into engagement with the latch716when the arrestment hook system102moves from the stowed position202toward the deployed position204. As the selector718pivots into engagement with the latch716, the selector718moves to a blocking position1008to prevent the latch716from capturing the hook404when the arrestment hook system102moves from the stowed position202to the deployed position204. As a result, the selector718blocks or restricts access to the capture chamber748of the directional lock704and causes the guide738to move past the capture chamber748and allows the arresting hook system102to move toward the deployed position204. The directional lock704enables the hook404to bypass the directional lock704when the arrestment hook system102moves from the stowed position202to the deployed position204. In some examples, actuation of the vertical actuator242between the first retracted position802and the first fully extended position1002causes the arresting hook system102to move between the stowed position202and the bypass position1000.

FIG.11Ais a side view of the arresting hook system102shown in another intermediate position1100(e.g., in a travel path between the bypass position1000and the deployed position204).FIG.11Bis a partial, enlarged view ofFIG.11A. To move the hook deployment assembly210from the bypass position1000ofFIG.10Ato the deployed position204, the arresting hook system102of the illustrated example employs the VDA252. Specifically, the VDA252is actuated to a partially extended position1102to move the hook404from the bypass position1000to the intermediate position1100when the arresting hook system102moves toward the deployed position204. Thus, as the arresting hook system102engages the directional lock704, the VDA252(e.g., the second piston414) is actuated from the second retracted position804to cause the hook deployment assembly210to extend from the bypass position1000toward the deployed position204. Specifically, actuation of the VDA252from the second retracted position804to the partially extended position1102causes movement of the hook404in a direction along the yaw axis134. Specifically, the second piston414imparts a force1104(e.g., a downward force) against the linkage arm504of the pivot assembly212. The coupler502enables the hook shank402to rotate in the second rotational direction730about the fifth pivot axis224a, thereby causing the hook shank402and, thus, the hook404to move toward the deployed position204. Referring toFIG.11B, when the guide738(e.g., the roller740) releases the directional lock704, the spring724of the directional lock704causes the latch716to rotate in the first rotational direction728about the first latch pivot axis720aand the second latch pivot axis722auntil the latch716engages the stop726. In turn, the latch716causes the selector718to move in the second rotational direction730about the selector pivot axis732a. In other words, the directional lock704is in the initial position810.

FIG.12Ais a side view of the arresting hook system102shown in the deployed position204.FIG.12Bis a partial, cross-sectional view ofFIG.12A. To move the hook404to the arresting position, the VDA252is actuated to a second fully extended position1202. As the VDA252continues to be actuated from the partially extended position1102ofFIG.11Ato the second fully extended position1202, the hook shank402rotates about the fifth pivot axis224avia the pivot assembly212in the second rotational direction730. In some examples, the linkage arm504can pivot in the second rotational direction730about the seventh pivot axis228a. The vertical actuator242is in the first fully extended position1002. In other words, as the VDA252moves to the second fully extended position1202, the second piston414imparts a force1204(e.g., a force in a direction of the yaw axis134) to the seventh joint228and/or the linkage arm504of the pivot assembly212. In turn, the second piston414causes the hook shank402to pivot in the second rotational direction730about the fifth pivot axis224aof the fifth joint224, causing the hook shank402and, thus, the hook404to move relative to the frame230in a direction along the yaw axis134. In other words, the coupler502and the linkage arm504rotate about the pin506to enable the hook shank402to pivot relative to the fifth pivot axis224abecause the hook shank402is fixed to the coupler502and/or the linkage arm504via the hook shank clevis408. Thus, actuation of the VDA252from the second retracted position804to the second fully extended position1202causes the arresting hook system102to move between the bypass position1000and the deployed position204. When the arresting hook system102is in the deployed position204, the hook404is in the arrestment position256(e.g., a cable capturing position). In the deployed position204and/or the arrestment position256, the hook404can engage a cable during a landing event.

FIG.13is a side view of the arresting hook system102shown in a hold down position1300. In the hold down position1300, the vertical actuator242is in the first fully extended position1002and the VDA252is in the second fully extended position1202. The VDA252of the illustrated example provides a strut for the hook shank402via the connection (e.g., the seventh joint228) between the second piston414and the linkage arm504of the pivot assembly212as the hook404(FIG.4) touches the ground surface112during a landing event. Thus, the VDA252counteracts forces to restrict or prevent the hook404from bouncing off of the ground surface112and over an arresting cable. In some examples, to counteract and/or reduce forces imparted to the trapeze deployment assembly208and the hook deployment assembly210when the hook engages a cable and/or the hook engages (e.g., bounces off) of the ground surface112during a landing event, the second cylinder416of the illustrated example can rotate about the sixth pivot axis226ain the first rotational direction728such that the second cylinder416is rotated toward the aft body304. Thus, although the VDA252is in the second fully extended position1202, the second cylinder416can rotate about the sixth pivot axis226avia the trunnion418and/or the second piston414can pivot relative to the seventh pivot axis228arelative to the frame230to react, dissipate, absorb and/or counteract certain forces. In such instance, the trapeze deployment assembly208remains in the over-center position626and/or the extended position246. In the deployed position204, the arrestment hook system102provides loads1304to hold down the hook404during the landing event.

FIG.14Ais a side view of the arresting hook system102in another intermediate position1400A. After deployment of the arresting hook system102(e.g., after a landing event), the arresting hook system102can be returned from the deployed position204to the stowed position202. In particular, the VDA252is moved from the second fully extended position1202(e.g., at which the arresting hook system102is in the deployed position204) toward the second retracted position804, the hook404moves along the yaw axis134from the ground surface112toward the directional lock704. Specifically, the second piston414imparts an upward force1404against the linkage arm504causing the pivot assembly212and the hook shank402to pivot about the fifth pivot axis224ain the first rotational direction728. Additionally, the vertical actuator242remains in the first fully extended position1002while the VDA252is retracted to move the arresting hook system102from the deployed position204toward the stowed position202.

FIG.14Bis a top view of the arresting hook system102in another intermediate position1400B. During arrestment with an arresting cable (e.g., during a landing event), the arresting hook system102can be move from the deployed position204to the intermediate position1400B based on arrestment forces1406that the arresting cable applies to the hook404. In the illustrated example ofFIG.14B, the arrestment forces1406cause the hook shank402to rotate in the first rotational direction728about the vertical axis234. As such, the hook shank402ofFIG.14Bis skewed at an angle1408relative to the longitudinal axis232. In other examples, the arrestment forces1406can cause the hook shank402to rotate in the second rotational direction730or to not rotate about the vertical axis234.

FIGS.15A and15Bare a partial, enlarged views of the arresting hook system102at different position prior to the inspection position206. Specifically, as the second piston414retracts to the second retracted position804, the guide738contacts the latch716of the directional lock704along a body1502of the latch716. As the second piston414moves to the second retracted position804, the guide738engages a trigger area1504of the latch716to cause the latch716to rotate in the first rotational direction728about the first latch pivot axis720aand the second latch pivot axis722a. The guide738, upon continued retraction of the VDA252, engages a rear surface1506of the selector718opposite the front surface1006and releases the latch716.

FIG.16Ais a side view of the arresting hook system102of the illustrated example shown in the inspection position206.FIG.16Bis a partial enlarged view ofFIG.16A. After the guide738releases the latch716from the position ofFIG.15B, the spring724causes the latch716to rotate in the first rotational direction728about the first latch pivot axis720aand the second latch pivot axis722asuch that the latch716engages the stop726and captures, traps or otherwise encloses the guide738(e.g., the roller740) in the capture chamber748. The rear surface1506of the selector718encloses the guide738in the capture chamber748. As a result, the arrestment hook system102of the illustrated example is in the inspection position206.

In the inspection position206, the vertical actuator242is in the first fully extended position1002and the VDA252is in the second retracted position804. Thus, as the VDA252retracts from the second fully extended position1202ofFIG.12Ato the second retracted position804ofFIG.16A, the VDA252causes the hook404to move from the arrestment position256(e.g., the deployed position204) to the inspection position206. In other words, the directional lock704is directional and does not allow the guide738to bypass the capture chamber748. Instead, when the arresting hook system102moves from the deployed position204toward the stowed position202, the directional lock704captures the guide738to retain the arrestment hook system102in the inspection position206. Thus, the directional lock704retains the hook404in the inspection position206in response to the hook deployment assembly210moving in a direction from the deployed position204toward the stowed position202. In the inspection position206, the trapeze deployment assembly208is in the extended position246(e.g., the over-center position626) and the cover264is in a partially open position. The inspection position206allows ground crew to inspect aspects of the hook404after a landing event. Specifically, the vertical actuator242in the first fully extended position1002via the trapeze deployment assembly208, the VDA252in the second retracted position804via the hook deployment assembly210, and/or the directional lock704supports the arresting hook system102in the inspection position206. The directional lock704maintains or supports the hook404to prevent the hook404from lowering or moving toward the deployed position204during an inspection event.

FIG.17Ais a side view of the arresting hook system102shown in an example release position1700.FIG.17Bis a partial, enlarged view ofFIG.17A. For example, the release position1700is provided when the arresting hook system102moves from the inspection position206to the stowed position202. In the illustrated example, the VDA252is in the second retracted position804and the vertical actuator242is retracted from the first fully extended position1002toward the first retracted position802. To move the arresting hook system102to the stowed position202, the first piston318is retracted to impart a force1702(e.g., an upward force) to the trapeze plate302to cause, via the coupling306, the aft body304to rotate in the second rotational direction730about the third pivot axis220a. In turn, rotation of the aft body304in the second rotational direction730causes the fourth joint222to move toward the OML262. In turn, the hook404moves in a forward direction1704toward the vertical actuator242along the roll axis132. Additionally, the second cylinder416pivots in the second rotational direction730about the sixth pivot axis226a. As a result, the guide738engages the rear surface1506(FIG.17B) of the selector718and causes the selector718to rotate in the second rotational direction730about the selector pivot axis732ato allow the guide738to exit the capture chamber748and/or disengage from the directional lock704(e.g., and to the release position1700).

FIG.18is a side view of the arrestment hook system102shown in another intermediate position1800between the inspection position206and the stowed position202as the vertical actuator242retracts toward first retracted position802. As the vertical actuator242continues to retract to the first retracted position802, the aft body304continues to rotate in the second rotational direction730about the third pivot axis220a, thereby causing the pivot assembly212and/or the hook shank402to move toward the vertical actuator242along the roll axis132and causing the guide738to move along the track710toward the passive lock702. Additionally, rotation of the aft body304in the second rotational direction730causes the cover764to move toward the cover closed position278. Referring toFIG.8A, upon retraction of the vertical actuator242, the arrestment hook system102moves to the stowed position202, the guide738is captured by the passive lock702, and the cover760moves to the cover closed position278.

FIG.19is a side view of another example arresting hook system1900disclosed herein. Many of the components of the example arresting hook system1900are substantially similar or identical to the components described above in connection with the arresting hook system102ofFIGS.1-18. As such, those components will not be described in detail again below. Instead, the interested reader is referred to the above corresponding descriptions for a complete written description of the structure and operation of such components. To facilitate this process, similar or identical reference numbers will be used for like structures inFIGS.19-25as used inFIGS.1-18. For example, the arresting hook system1900of the illustrated example includes a trapeze deployment assembly208, a hook deployment assembly210, a vertical actuator242and a VDA252. The arresting hook system1900of the illustrated example includes the primary lock1902. The primary lock1902(e.g., an uplock) includes a lock assembly1904that includes a hook1906, a body1908and a release lever1910. The hook1906engages a flange1912formed on an aft body304of the trapeze deployment assembly208when the arresting hook system1900is in a stowed position202. To release the primary lock1902, the release lever1910is pivoted relative to the body1908to cause the hook1906to release or disengage from the flange1912of the aft body304. The release lever1910can be operated by a controller, an actuator, a cable, pull-cord, and/or any other suitable actuator.

Additionally, the arresting hook system1900of the illustrated example includes another lock assembly1914. The lock assembly1914of the illustrated example includes a passive lock1916and a bypass or directional lock1918spaced from the passive lock1916. A hook shank402of the illustrated example includes a guide1920to interact (e.g., engage) with the passive lock1916and the directional lock1918. The guide1920of the illustrated example has a first portion or first end1922and a second portion or second end1924opposite the first end1922. The first end1922is located upstream from a hook404of the hook shank402and the second end1924is located downstream of the hook404. Stated differently, the first end1922is oriented toward the passive lock1916to interact with the passive lock1916and the second end1924is oriented toward the directional lock1918to interact with the directional lock1918. The passive lock1916is fixed to a frame (e.g., the frame230) of an aircraft (e.g., the aircraft100ofFIG.1). The directional lock1918is pivotally coupled to the frame230about a latch joint1926defining a latch pivot axis1926athat enables the directional lock1918to rotate relative to the frame in a first rotational direction728and a second rotational direction730.

FIG.20is a perspective view of the passive lock1916of the example arresting hook system ofFIG.19. The passive lock1916of the illustrated example includes a base wall2002(e.g., a plate) defining a retainer aperture2004. A guide wall2006(e.g., a partial or semi-annular wall) extends in a direction away from the base wall2002and defines a pocket2008. The guide wall2006guides the first end1922of the guide1920toward the retainer aperture2004.

FIGS.21A and21Bare perspective views of the directional lock1918of the example arresting hook system ofFIG.19. The directional lock1918of the illustrated example includes a latch body2102and a selector2104. The latch body2102of the illustrated example includes a capture aperture2106, a deflection region2108(e.g., a deflector), and a pivot region2110that defines a pivot aperture2112for pivotally coupling the directional lock1918to the frame230. The pivot aperture2112defines the latch pivot axis1926aof the latch joint1926ofFIG.19. The selector2104of the illustrated example is a flap2114(e.g., an arm) having a first end2116pivotally coupled to the latch body2102. The selector2104pivots relative to the latch body2102about a selector pivot axis2104ato cover or block the capture aperture2106and uncover the capture aperture2106. Although not shown, the selector2104includes a biasing element (e.g., a torsion spring) to bias the selector2104in a direction away from the capture aperture2106.

FIGS.22A-22Dare side views of the arresting hook system1900ofFIG.19at different positions when the arresting hook system1900moves from a stowed position202toward a deployed position204. Referring toFIG.22A, the vertical actuator242is actuated from a first retracted position802(FIG.8A) toward a first fully extended position1002(FIG.10A) to cause the hook shank402of the illustrated example to move aft along the roll axis132toward the directional lock1918. In turn, the guide1920moves in a direction from the passive lock1916toward the directional lock1918. For example,FIG.22Aillustrates the guide1920in a first position2200in which the first end1922of the guide1920is removed from the retainer aperture2004of the passive lock1916. The directional lock1918is in an initial position2202. In the initial position2202, the latch body2102is biased in the second rotational direction730to cause the deflection region2108to engage a stop2204of the frame. Additionally, the flap2114is in a non-blocking position2206. Specifically, a spring biases the selector2104in the second rotational direction730about the selector pivot axis2104ato the non-blocking position2206to expose the capture aperture2106(FIG.21A).

Referring toFIG.22B, as the vertical actuator242extends toward the first fully extended position1002(FIG.10A), the directional lock1918moves to a bypass position2208. Specifically, in the bypass position2208, the flap2114is in a blocking position2210. In particular, as the hook shank402moves toward the directional lock1918as the vertical actuator242is actuated toward the first fully extended position1002, the second end1924of the guide1920engages a first surface2212of the selector2104to cause the selector2104to pivot against a spring force in the first rotational direction728about the selector pivot axis2104a. In the blocking position2210, the selector2104prevents or restricts access to the capture aperture2106of the latch body2102. As a result, the guide1920bypasses the directional lock1918.

Referring toFIG.22C, to continue movement of the arresting hook system1900from the bypass position2208ofFIG.22Bto the deployed position204, the VDA252is actuated from the second retracted position804toward the second fully extended position1202(FIG.12A) to move the hook shank402and, thus, the hook404from the bypass position2208ofFIG.22Bto the deployed position204. To prevent interference between the directional lock1918and the guide1920when the directional lock1918is in the bypass position2208, the guide1920causes the latch body2102to pivot about the latch pivot axis1926ain the first rotational direction728to a deflection position2214such that the deflection region2108moves away or disengages from the stop2204.

As shown inFIG.22D, as the guide1920releases the flap2114and/or the latch body2102, the selector2104rotates in the second rotational direction730about the selector pivot axis2104aand the latch body2102rotates in the second rotational direction730about the latch pivot axis1926auntil the deflection region2108engages the stop2204(seeFIG.22A). In other words, the directional lock1918returns to the initial position2202ofFIG.22Aafter the guide1920bypasses the directional lock1918.

FIGS.23A and23Bare partial side views of the arresting hook system1900ofFIG.19shown at intermediate positions2302and2304as the arresting hook system1900moves from the deployed position204toward the stowed position202after an arrestment event. In other words, the intermediate positions2302and2304are positions of a return path in which the VDA252retracts from the second fully extended position1202to the second retracted position804. As the hook deployment assembly210moves to the non-engagement intermediate position258, the guide1920engages the directional lock1918. In particular, the second end1924of the guide1920engages the deflection region2108of the latch body2102to cause the latch body2102to pivot or rotate in the first rotational direction728about the latch pivot axis1926afrom the initial position2202ofFIG.23Ato a deflected position2306ofFIG.23B. In other words, the latch body2102moves about the latch pivot axis1926ain the first rotational direction728to cause the deflection region2108(e.g., an end of the latch body2102opposite the latch pivot axis1926a) to move away from the stop2204. The selector2104remains in the non-blocking position2206.

FIG.24is a partial side view of the arresting hook system1900ofFIG.19shown in an inspection position206. In the inspection position206, the VDA252is in the second retracted position804and the vertical actuator242is in the first fully extended position1002. As the VDA252moves to the second retracted position804, the second end1924of the guide1920moves into the capture aperture2106of the latch body2102. A biasing element of the latch joint1926causes the latch body2102to pivot in the second rotational direction730about the latch pivot axis1926auntil the deflection region2108engages the stop2204. The selector2104is biased toward the non-blocking position2206about the selector pivot axis2104aand, thus, does not interfere (e.g., engage) with the guide1920.

FIG.25is a partial side view of the arresting hook system1900ofFIG.19shown in an intermediate position2500as the arresting hook system1900moves from the inspection position206toward the stowed position202. To remove the guide1920from the capture aperture2106, the vertical actuator242is moved from the first fully extended position1002toward the first retracted position802. In response, the second end1924of the guide1920disengages or removes from the capture aperture2106. The selector2104is biased via a spring toward the non-blocking position2206and does not interfere (e.g., engage) with the guide1920as the guide1920withdraws from the capture aperture2106and moves toward the passive lock1916.

FIG.26is a partial side view of the arresting hook system1900ofFIG.19shown in the stowed position202. In the stowed position202, the vertical actuator242is retracted to the first retracted position802, which causes the hook shank402(e.g., via the pivot assembly212) to move forward along the roll axis132. The first end1922of the guide1920is positioned in the retainer aperture2004of the passive lock1916.

Although each example arrestment hook systems disclosed above have 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. One example's features are not mutually exclusive to another example's features. Instead, the scope of this disclosure encompasses any combination of any of the features.

Example methods, apparatus, systems, and articles of manufacture to implement arrestment hook systems are disclosed herein. Further examples and combinations thereof include the following:

Example 1 includes a pivot assembly for use with an arresting hook, the pivot assembly comprising a coupler having a first opening defining a first axis and a second opening defining a second axis, the first opening transverse relative to the second opening, a linkage arm having a body and an arm, the body including a third opening defining a third axis, the first opening of the coupler to receive the body of the linkage arm such that the second opening of the coupler coaxially aligns with the third opening of linkage arm, and a pin to extend through the second opening and the third opening to couple the coupler and the linkage arm.

Example 2 includes the pivot assembly of example 1, wherein the arm extends rearward of the body.

Example 3 includes the pivot assembly of any of examples 1-2, wherein an end of the arm opposite the body includes a clevis.

Example 4 includes the pivot assembly of any of examples 1-3, wherein the clevis defines a fourth opening defining a fourth axis, wherein the third axis of the third opening is parallel relative to the fourth axis of the fourth opening.

Example 5 includes the pivot assembly of any of examples 1-4, wherein the fourth opening is spaced from the third opening by a distance defined by a length of the arm.

Example 6 includes a pivot assembly for use with an arresting hook system, the pivot assembly comprising a coupler to couple to a clevis of a hook shank, a linkage arm having a shaft and an arm, the shaft to extend through the clevis of the hook shank and the coupler, the arm to extend at angle relative to the shaft, and a pin to extend through the coupler and the shaft of the linkage arm, the pin to couple the coupler and the linkage arm, an axis of the pin to intersect a longitudinal axis of the shaft when the pin is coupled to the coupler and the linkage arm.

Example 7 includes the pivot assembly of example 6, wherein the coupler includes a first bore defining the longitudinal axis, the first bore to receive the shaft of the linkage arm.

Example 8 includes the pivot assembly of any of examples 6-7, wherein the coupler includes a second bore to receive the pin, the second bore being transverse relative to the longitudinal axis of the coupler.

Example 9 includes the pivot assembly of any of examples 6-8, wherein the shaft includes a third bore, the third bore aligning with the second bore when the shaft is positioned in the coupler.

Example 10 includes the pivot assembly of any of examples 6-9, wherein the pin at least one of restricts or prevents lateral and rotational movement of the linkage arm relative to the coupler along the longitudinal axis.

Example 11 includes the pivot assembly of any of examples 6-10, wherein the arm of the linkage arm includes a connector to couple to a piston of a vertical damper actuator of the arresting hook system.

Example 12 includes the pivot assembly of any of examples 6-11, wherein the coupler is to pivotally couple the arresting hook shank and a trapeze of the arresting hook system.

Example 13 includes an arresting hook system comprising a trapeze assembly, the trapeze assembly including a pivot plate, a hook assembly including a hook and a hook shank to support the hook, the hook shank including a clevis opposite the hook, and a pivot assembly to couple the trapeze assembly and the hook assembly, the pivot assembly including a coupler positioned in the clevis of the hook shank, a linkage arm having a shaft and an arm extending rearward of the shaft, the shaft positioned in an opening of the clevis of the hook shank and a first opening of the coupler, and a pin to couple the coupler and the shaft of the linkage arm, the pin defining a lateral pivot axis that intersects a vertical pivot of the shaft of the linkage arm.

Example 14 includes the arresting hook system of example 13, wherein the pin is positioned in a second opening of the coupler and a third opening of the shaft that aligns with the second opening when the shaft is positioned in the first opening of the coupler.

Example 15 includes the arresting hook system of any of examples 13-14, wherein the pin is perpendicular relative to a longitudinal axis of the shaft.

Example 16 includes the arresting hook system of any of examples 13-15, wherein the arm includes a second clevis at an end of the arm.

Example 17 includes the arresting hook system of any of examples 13-16, wherein the second clevis is to receive a rod end of a vertical damping actuator of the arresting system.

Example 18 includes the arresting hook system of any of examples 13-17, wherein the coupler includes a cam surface to engage a lateral damper of the arresting system.

Example 19 includes the arresting hook system of any of examples 13-18, wherein the pin couples the hook shank and the pivot plate of the trapeze assembly.

Example 20 includes the arresting hook system of any of examples 13-19, wherein the pin includes retainers at respective ends of the pin, the retainers to engage respective sides of the pivot plate of the trapeze assembly.

Example 21 includes a locking assembly for an arresting hook system comprising a track coupled to a frame of an aircraft, the track including a forward end and an aft end opposite the forward end, the track including a first lock positioned at the forward end and a second lock positioned at the aft end, and a guide coupled to a hook shank of the arresting hook system, the guide to move along at least a portion of the track, the guide to engage the first lock when the hook shank is in a stowed position, the guide to bypass the second lock as the hook shank moves from the stowed position to a deployed position.

Example 22 includes the locking assembly of example 21, wherein the guide is to engage the second lock as the hook shank moves from the deployed position to the stowed position, the hook shank to be in an intermediate position when the guide engages the second lock, the intermediate position between the stowed position and the deployed position.

Example 23 includes the locking assembly of any of examples 21-22, wherein the first lock includes a capture hook at the forward end of the track.

Example 24 includes the locking assembly of any of examples 21-23, wherein the second lock is a directional lock.

Example 25 includes the locking assembly of any of examples 21-24, wherein the second lock includes a spring latch and a selector.

Example 26 includes the locking assembly of any of examples 21-25, wherein the spring latch is coupled to the frame of the aircraft, the spring latch to rotate relative to the frame about a first latch joint.

Example 27 includes the locking assembly of any of examples 21-26, wherein the selector is coupled to the track, the selector to rotate relative to the track about a selector joint different than the first latch joint.

Example 28 includes the locking assembly of any of examples 21-27, wherein the guide includes a roller and a bracket, the roller coupled to a hook shank of the arresting hook system via the bracket.

Example 29 includes an arresting hook system for an aircraft comprising a trapeze deployment assembly, a hook deployment assembly including a hook shank and a hook, the hook deployment assembly pivotally coupled to the trapeze deployment assembly, and a locking assembly coupled to a frame of the aircraft, the locking assembly including a passive lock and a directional lock, the passive lock to retain the hook when the hook deployment assembly is in a stowed position, the directional lock to enable the hook to bypass the directional lock when the hook deployment assembly moves from the stowed position to a deployed position, the directional lock to retain the hook of the hook deployment assembly in an intermediate position when the hook deployment assembly moves from the deployed position to the stowed position.

Example 30 includes the arresting hook system of example 29, wherein the locking assembly includes a track defining a length between a first end and a second end opposite the first end, the passive lock positioned at the first end, the directional lock positioned at the second end.

Example 31 includes the arresting hook system of any of examples 29-30, wherein the passive lock and the directional lock are positioned in a travel path of the hook, the travel path being along the track between the first end and the second end.

Example 32 includes the arresting hook system of any of examples 29-31, wherein the passive lock includes a pocket positioned in the travel path, the pocket oriented toward the directional lock.

Example 33 includes the arresting hook system of any of examples 29-32, wherein the directional lock includes a selector and a latch, the selector coupled to rotate relative to the track, the selector to rotate to a blocking position based on movement of the hook from the stowed position to the deployed position, the selector to prevent the latch from capturing the hook when the selector is in the blocking position.

Example 34 includes the arresting hook system of any of examples 29-33, wherein the hook shank includes a roller, the passive lock to engage the roller when the hook deployment assembly moves into the stowed position, the directional lock to engage the roller when the hook deployment assembly moves into an intermediate position from the deployed position, the intermediate position between the stowed position and the deployed position.

Example 35 includes an aircraft comprising an arresting hook system including a trapeze deployment assembly, a hook deployment assembly including a hook coupled to a hook shank, the hook shank including a roller, a pivot assembly to pivotally couple the trapeze deployment assembly and the hook deployment assembly, and a dual lock coupled to a frame of the aircraft, the dual lock including a track defining a first end and a second end opposite the first end, the dual lock including a passive lock positioned at the first end and a directional lock positioned at the second end, the passive lock including a pocket to receive the roller when the arresting hook system is in a stowed position, the roller to bypass the directional lock when the arresting hook system moves from the stowed position to a deployed position, the direction lock to capture the roller when the arresting hook system moves from the deployed position toward the stowed position, the directional lock to capture the roller when the arresting hook system is in an inspection position prior to the hook moving to the stowed position.

Example 36 includes the aircraft of example 35, wherein the directional lock includes a latch and a selector, the latch coupled to a spring, the selector coupled to a spring hinge.

Example 37 includes the aircraft of any of examples 35-36, wherein the latch is pivotally coupled to the frame of the aircraft about a first pivot axis, the spring to bias the latch in a first direction about the first pivot axis, the first direction relative to the frame of the aircraft.

Example 38 includes the aircraft of any of examples 35-37, wherein the selector is pivotally coupled to the track about a second pivot axis different than the first pivot axis, the spring hinge to bias the selector in the first direction about the second pivot axis and toward the latch.

Example 39 includes the aircraft of any of examples 35-38, wherein the latch is to move in a second direction about the first pivot axis when the arresting hook system moves from the deployed position toward the stowed position, the second direction opposite the first direction.

Example 40 includes the aircraft of any of examples 35-39, wherein the selector is to move in the second direction about the second pivot axis to move the arresting hook system from the inspection position to the stowed position.

Example 41 includes an arresting hook system for an aircraft, the arresting hook system comprising a linkage assembly defining a trapeze deployment assembly of the arresting hook system, the linkage assembly including a forward body defining a first joint and a second joint opposite the first joint, the forward body longitudinally extending between the first joint and the second joint, the forward body pivotally coupled to a frame of the aircraft via the first joint, an aft body defining a third joint, a fourth joint, and a primary pivot joint, the aft body pivotally coupled to the frame via the third joint, and a coupling assembly pivotally coupled to the second joint of the forward body and the fourth joint of the aft body, movement of the forward body to cause movement of the aft body via the coupling assembly, a pivot assembly to pivotally couple a hook shank to the primary pivot joint of the aft body, a vertical actuator coupled to the forward body and the frame of the aircraft, the vertical actuator to move the arresting hook system between a stowed position and an intermediate position, and a vertical damper actuator (VDA) including a cylinder and a piston, the cylinder pivotally coupled to the frame of the aircraft via a VDA pivot joint, the VDA to rotate relative to the frame of the aircraft, the piston having an end operatively coupled to the pivot assembly, the VDA to move the arresting hook system between the intermediate position and a deployed position.

Example 42 includes the arresting hook system of example 41, wherein the pivot assembly includes a coupler and a linkage arm extending rearward from the coupler.

Example 43 includes the arresting hook system of any of examples 41-42, wherein the coupler couples the hook shank to the primary pivot joint of the aft body and the linkage arm couples to the end of the piston of the VDA via a clevis joint, the end of the piston and the linkage arm defining the clevis joint.

Example 44 includes the arresting hook system of any of examples 41-43, wherein the linkage assembly defines a first bar linkage including a first forward link between the first joint and the second joint, a first coupler link between the second joint of the forward body and the fourth joint of the aft body, a first aft link between the fourth joint of the aft body and the third joint of the aft body, and a first ground link between the third joint of the aft body and the first joint of the forward body.

Example 45 includes the arresting hook system of any of examples 41-44, wherein the pivot assembly, the aft body, and the VDA define a second bar linkage.

Example 46 includes the arresting hook system of any of examples 41-45, wherein the second bar linkage includes a second forward link between the third joint and the primary pivot joint, a second coupler link between the primary pivot joint and the clevis joint of the linkage arm, a second aft link between the clevis joint and the VDA pivot joint, and a second ground link between the third joint of the first aft link and the VDA pivot joint.

Example 47 includes the arresting hook system of any of examples 41-46, wherein the vertical actuator is to move the first bar linkage to an on-center alignment, wherein the first forward link and the first coupler link are aligned when the first bar linkage is in the on-center alignment.

Example 48 includes the arresting hook system of any of examples 41-47, wherein the VDA is to move the arresting hook system after the vertical actuator moves the first bar linkage to the on-center alignment.

Example 49 includes the arresting hook system of any of examples 41-48, wherein the pivot assembly is to nest within the aft body when the arresting hook system is in the stowed position.

Example 50 includes the arresting hook system of any of examples 41-49, wherein the second bar linkage defines a transmission angle between the second coupler link and the second aft link.

Example 51 includes the arresting hook system of any of examples 41-50, wherein the transmission angle is between 40 and 50 degrees when the arresting hook system in in the deployed position.

Example 52 includes the arresting hook system of any of examples 41-51, wherein the transmission angle is between 145 and 155 degrees when the arresting hook system is in the intermediate position.

Example 53 includes the arresting hook system of any of examples 41-52, wherein the VDA is pivotally coupled to the frame of the aircraft via a trunnion, the cylinder having a length, the trunnion positioned along the length of the cylinder.

Example 54 includes an arresting hook apparatus to be stowed within an outer mold line of an aircraft, the arresting hook apparatus comprising a trapeze deployment assembly including a vertical actuator to move the trapeze deployment assembly between a stowed position and an intermediate position, and a hook deployment assembly including a vertical damper actuator (VDA) and a hook, the VDA pivotally coupled to a primary structure of the aircraft via a trunnion, the VDA to move the hook deployment assembly between the intermediate position and a deployed position, the VDA to dampen arrestment loads when the hook deployment assembly is in the deployed position.

Example 55 includes the arresting hook apparatus of example 54, wherein the trapeze deployment assembly defines a first bar linkage including a first forward link, a first coupler link, a first aft link, and a first ground link.

Example 56 includes the arresting hook apparatus of any of examples 54-55, wherein the hook deployment assembly defines a second bar linkage including a second forward link, a second coupler link, a second aft link, and a second ground link.

Example 57 includes the arresting hook apparatus of any of examples 54-56, wherein the trapeze deployment assembly includes an aft body defining the first aft link of the first bar linkage and the second forward link of the second bar linkage, the first aft link and the second forward link rotatably interlocked via the aft body.

Example 58 includes the arresting hook apparatus of any of examples 54-57, wherein the VDA includes a piston disposed within a cylinder having a length, the trunnion positioned adjacent to a midpoint of the length.

Example 59 includes an aircraft comprising an arresting hook system disposed within an outer mold line of the aircraft when the arresting hook system is in a stowed position, the arresting hook system disposed at least partially outside of the outer mold line when the arresting hook system is in at least one of an intermediate position or a deployed position, the arresting hook system including a hook shank having a first end and a second end opposite the first end, a hook coupled to the first end of the hook shank, a linkage assembly including a forward body, a coupling body, and an aft body, the second end of the hook shank coupled to the aft body via a primary pivot joint, the forward body aligned with the coupling when the arresting hook system is in the intermediate position and the deployed position, a vertical actuator coupled to a frame of the aircraft and the forward body to deploy the arresting hook system between the stowed position and the intermediate position, and a vertical damper actuator pivotally coupled to the frame of the aircraft via a trunnion, the vertical damper actuator to deploy the arresting hook system between the intermediate position and the deployed position.

Example 60 includes the aircraft of example 59, wherein a first position of the primary pivot joint associated with the stowed position is forward of a second position of the primary pivot joint associated with the intermediate position.