Variable thrust catapult

A rocket catapult assembly for an ejection seat may comprise a motor assembly including a proximal end and a distal end, a first cartridge, and a second cartridge. The first cartridge and the second cartridge may be configured to provide a variable thrust based on an occupant's weight. The first cartridge may provide a thrust corresponding to a relatively light weight occupant, the second cartridge may provide a thrust corresponding to a relatively average weight occupant, and the first cartridge and second cartridge may provide a combined thrust corresponding to a relatively heavy weight occupant.

FIELD

The present disclosure relates to escape systems, and more specifically, to variable thrust catapults for multi weight occupants.

BACKGROUND

Ejection systems are designed to expel pilots from an aircraft cockpit. Ejection seats in high performance aircraft benefit from safely removing the pilot or other occupant from the disabled aircraft across a wide variety of aircraft speed regimes, altitudes and aircraft attitudes. Occupants of aircrafts may be various weights ranging from a relatively light weight individual to a relatively heavy individual, which may prevent a single amount of force of thrust to propel an occupant out an aircraft from being desirable.

SUMMARY

A rocket catapult assembly for use in an ejection seat system of an aircraft is disclosed herein. The rocket catapult assembly may comprise: a motor assembly comprising a motor outer casing and a motor inner casing extending from a proximal end to a distal end, the motor inner casing defining a chamber; a first cartridge configured to provide a first thrust of the rocket catapult assembly, the first cartridge in fluid communication with the chamber; and a second cartridge configured to provide a second thrust of the rocket catapult assembly, the second cartridge in fluid communication with the chamber, the second thrust being greater than the first thrust.

In various embodiments, the rocket catapult assembly may further comprise a breach disposed at the distal end of the motor assembly, wherein the first cartridge and the second cartridge are housed in the breach. The breach may comprise a first manifold and a second manifold. The first cartridge may be disposed in the first manifold, and the second cartridge may be disposed in the second manifold. The rocket catapult assembly may further comprise a first ignitor and a second ignitor, wherein the first ignitor is in communication with the first cartridge and the second ignitor is in communication with the second cartridge. The first cartridge and the second cartridge may be disposed in the chamber. The rocket catapult assembly may further comprise a first manifold and a second manifold, wherein the first manifold and the second manifold are disposed in the chamber, and wherein the first cartridge is disposed in the first manifold and the second cartridge is disposed in the second manifold.

An aircraft ejection seat system is disclosed herein. The aircraft ejection seat system may comprise: a seat pan; a seat back coupled to the seat pan; and a rocket catapult assembly coupled to the seat back, the rocket catapult assembly comprising: a motor assembly comprising a motor outer casing and a motor inner casing extending from a proximal end to a distal end, the motor inner casing defining a chamber; a first cartridge configured to provide a first thrust of the rocket catapult assembly, the first cartridge in fluid communication with the chamber; and a second cartridge configured to provide a second thrust of the rocket catapult assembly, the second cartridge in fluid communication with the chamber, the second thrust being greater than the first thrust.

In various embodiments, the aircraft ejection seat system may further comprise a first ignitor in communication with the first cartridge and a second ignitor in communication with the second cartridge. The aircraft ejection seat system may further comprise a display switch configured to be in a first position, a second position, or a third position, wherein the display switch is configured to create a first electrical or energetic connection and enable the first ignitor in response to being in the first position, wherein the display switch is configured to create a second electrical connection and enable the second ignitor in response to being in the second position, and wherein the display switch is configured to create the first electrical connection and the second electrical connection in response to being in the third position. The aircraft ejection seat system may further comprise a load cell coupled to the seat pan. The aircraft ejection seat system may further comprise a controller in electrical communication with the load cell, the first ignitor, and the second ignitor. The controller may be configured to enable the first ignitor only when a weight below a first threshold weight is measured by the load cell. The controller may be configured to enable the first ignitor and the second ignitor when the weight is measured by the load cell as being above a second threshold weight, wherein the second threshold weight is greater than the first threshold weight. The controller may be configured to enable the second ignitor only when the weight measured by the load cell is between the first threshold weight and the second threshold weight. The aircraft ejection seat system may further comprise a breach, a first manifold, and a second manifold, wherein the first manifold and the second manifold are disposed in the breach, and wherein the first cartridge is disposed in the first manifold and the second cartridge is disposed in the second manifold.

A method of controlling an operating pressure of a rocket catapult assembly for an ejection seat of an aircraft is disclosed herein. The method may comprise: compressing a load cell disposed in a seat pan of the ejection seat; and enabling or disabling a first ignitor in response to compressing the load cell, wherein the first ignitor is coupled to, and in communication with, a first cartridge of the rocket catapult assembly, the first cartridge configured to provide a first thrust of the rocket catapult assembly; enabling or disabling a second ignitor in response to compressing the load cell, wherein the second ignitor is coupled to, and in communication with, a second cartridge of the rocket catapult assembly, the second cartridge configured to provide a second thrust of the rocket catapult assembly, the second thrust greater than the first thrust.

In various embodiments, the first ignitor may be enabled when the load cell measures a weight below a first threshold weight and when the load cell measures the weight above a second threshold weight, wherein the second threshold weight is greater than the first threshold weight. The second ignitor may be enabled when the load cell measures the weight being between the first threshold weight and the second threshold weight, and wherein the second ignitor is enabled when the load cell measures the weight being greater than the second threshold weight. The method may further comprise comparing a measured weight by the load cell to a first threshold weight and a second threshold weight.

DETAILED DESCRIPTION

The detailed description of exemplary embodiments herein makes reference to the accompanying drawings, which show exemplary embodiments by way of illustration. While these exemplary embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosures, it should be understood that other embodiments may be realized and that logical changes and adaptations in design and construction may be made in accordance with this disclosure and the teachings herein. Thus, the detailed description herein is presented for purposes of illustration only and not of limitation.

The scope of the disclosure is defined by the appended claims and their legal equivalents rather than by merely the examples described. For example, the steps recited in any of the method or process descriptions may be executed in any order and are not necessarily limited to the order presented. Furthermore, any reference to singular includes plural embodiments, and any reference to more than one component or step may include a singular embodiment or step. Also, any reference to tacked, attached, fixed, coupled, connected or the like may include permanent, removable, temporary, partial, full and/or any other possible attachment option. Additionally, any reference to without contact (or similar phrases) may also include reduced contact or minimal contact. Surface shading lines may be used throughout the figures to denote different parts but not necessarily to denote the same or different materials.

A variable thrust rocket catapult assembly for use in an aircraft ejection system is disclosed herein. The variable thrust catapult assembly comprises at least a first cartridge and a second cartridge. The first cartridge is configured to provide a first thrust to rocket catapult assembly and second cartridge is configured to provide a second thrust to rocket catapult assembly. The first thrust is less than the second thrust. The combined first cartridge and the second cartridge are configured to provide a maximum thrust to rocket catapult assembly. The maximum thrust to catapult assembly may correspond to a maximum weight occupant of the aircraft ejection system. The aircraft ejection system may use manually selection of which cartridges to use (i.e., a switch selecting an occupant's weight), or the aircraft ejection system may automatically select which cartridges to use (i.e., a sensor in communication with ignitors for the cartridges).

With reference toFIG. 1A, an aircraft ejection system10is shown, in accordance with various embodiments. Aircraft ejection system10may be installed in aircraft12to expel an ejection seat14and an occupant16of ejection seat14from a cockpit18of aircraft12. Ejection seat14may be urged from cockpit18by a propulsion system20. In accordance with various embodiments, ejection seat14includes rocket catapult assembly200. Rocket catapult assembly200may comprise an element of propulsion system20and be configured to extract the ejection seat14from cockpit18.

With additional reference toFIG. 1B, ejection seat14is illustrated with rocket catapult assembly200in an inactive state, in accordance with various embodiments. Ejection seat14includes a seat back102and a seat pan104. The rocket catapult assembly200is coupled to seat back102. In various embodiments, an ejection handle106may be located proximate a front108of seat pan104. Front108of seat pan104is generally opposite, or distal, seat back102. WhileFIG. 1Bshows ejection handle106located at front108of seat pan104, it is further contemplated and understood that ejection handle106may be located anywhere that is accessible to an occupant of ejection seat14. For example, ejection handle106may be located on a side112of seat pan104or a headrest114of seat back102.

With additional reference toFIG. 2, ejection seat14is illustrated with rocket catapult assembly200in an active state, in accordance with various embodiments. Ejection handle106may be configured to initiate an ejection sequence upon actuation. For example, occupant16pulling ejection handle106in the direction of arrow110may activate the rocket catapult assembly200. Rocket catapult assembly200may comprise a motor assembly202, a breach204, a catapult cartridge unit205, a nozzle assembly208, and a motor cap assembly210. In response to activation, the catapult cartridge unit205may ignite and tend to produce relatively hot, high pressure, gas. Breach204may be coupled to the aircraft12and comprise a motor tube206disposed within the motor assembly202. In various embodiments, motor cap assembly210may direct a first portion of gas to the breach204tending thereby to drive the motor tube206outward of the motor assembly202and cause ejection seat14to be expelled from cockpit18. In various embodiments, motor tube206may separate from the motor assembly202in response to ejection seat14departing from the cockpit18. In various embodiments, the breach204may include an integral gas generator which, in response to activation, may drive the motor tube206outward of the motor assembly202and cause ejection seat14to be expelled from cockpit18. In various embodiments, the motor assembly202may be ignited in response to motor tube206exiting the motor assembly202.

Referring now toFIG. 3, a cross-section of a portion of a rocket catapult assembly300in an inactive state, in accordance with various embodiments, is illustrated. The rocket catapult assembly300may comprise a proximal end302and a distal end304disposed opposite the proximal end302. The proximal end302may be configured to be coupled to an aircraft (e.g., aircraft12fromFIG. 1A). The distal end304may be configured to be coupled to an ejection seat (e.g., ejection seat14fromFIG. 1A). The rocket catapult assembly300may further comprise a motor outer case310extending from proximal end302to distal end304, a head cap320coupled to the motor outer case310at distal end304, and a motor inner case330disposed radially inward from motor outer case310. The head cap320may be coupled to the motor outer case310by any method known in the art, such as a lock ring, or the like. In various embodiments, the motor inner case330defines a chamber332. The chamber332may be in fluid communication with a motor cap assembly (e.g., motor cap assembly210inFIG. 2).

Referring now toFIG. 4, a schematic view of a portion of a rocket catapult assembly300, in accordance with various embodiments, is illustrated. In various embodiments, a rocket catapult assembly300may further comprise, a first cartridge342, a second cartridge344, a first ignitor352and a second ignitor354. In various embodiments, the first ignitor352and the second ignitor354may be any ignitor known in the art, such as a pyrotechnic ignitor, a low current igniter, or the like. The first ignitor352may be configured to ignite first cartridge342and the second ignitor354may be configured to ignite second cartridge344. In various embodiments, whether first ignitor352, second ignitor354, or both first ignitor352and second ignitor354are ignited is based on an occupant weight in an aircraft. For example, for a relatively lightweight occupant, only first ignitor352may be ignited. For a relatively average weight occupant, only second ignitor354may be ignited. For a relatively heavy occupant both first ignitor352and second ignitor354may be ignited.

In various embodiments, first cartridge342may be sized to provide a first thrust in proportion to a lightweight occupant, second cartridge344may be sized to provide a second thrust in proportion to a medium weight occupant, and the combination of first cartridge342and second cartridge344may be sized to provide a third thrust in proportion to a heavy weight occupant. In various embodiments, the first thrust is less than the second thrust and the second thrust is less than the third thrust.

In various embodiments, rocket catapult assembly300further comprises a first manifold362and a second manifold364. The first manifold362may house first cartridge342and the second manifold364may house second cartridge344. In various embodiments, the first manifold362and the second manifold364may keep the first cartridge342and the second cartridge344distinct and separate as to prevent both from igniting when only a single cartridge is ignited. In various embodiments, first manifold362and second manifold364are disposed in chamber332. In various embodiments, proximal end302comprises a breach303. In various embodiments, the breach303is configured to be coupled to a floor of an aircraft.

In various embodiments, with brief reference toFIG. 5, a rocket catapult assembly400may comprise a proximal end configured to house manifolds. For example, rocket catapult assembly400comprises a proximal end402including a first manifold462and a second manifold464. In various embodiments a breach403of rocket catapult assembly400houses a first cartridge442in first manifold462and houses a second cartridge444in a second manifold464. The first manifold462and the second manifold464are in fluid communication with chamber332of rocket catapult assembly400.

In various embodiments and with additional reference toFIG. 6, a schematic block diagram of a control system600for first ignitor352and second ignitor354is illustrated. Control system600includes a controller602in electronic communication with a load cell604, the first ignitor352and the second ignitor354. In various embodiments, controller602may be integrated into computer systems onboard aircraft12and/or ejection seat14. In various embodiments, controller602may be configured as a central network element or hub to access various systems, engines, and components of control system600. Controller602may comprise a network, computer-based system, and/or software components configured to provide an access point to various systems, engines, and components of control system600. In various embodiments, controller602may comprise a processor. In various embodiments, controller602may be implemented in a single processor. In various embodiments, controller602may be implemented as and may include one or more processors and/or one or more tangible, non-transitory memories and be capable of implementing logic. Each processor can be a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof. Controller602may comprise a processor configured to implement various logical operations in response to execution of instructions, for example, instructions stored on a non-transitory, tangible, computer-readable medium configured to communicate with controller602.

System program instructions and/or controller instructions may be loaded onto a non-transitory, tangible computer-readable medium having instructions stored thereon that, in response to execution by a controller, cause the controller to perform various operations. The term “non-transitory” is to be understood to remove only propagating transitory signals per se from the claim scope and does not relinquish rights to all standard computer-readable media that are not only propagating transitory signals per se. Stated another way, the meaning of the term “non-transitory computer-readable medium” and “non-transitory computer-readable storage medium” should be construed to exclude only those types of transitory computer-readable media which were found in In Re Nuijten to fall outside the scope of patentable subject matter under 35 U.S.C. § 101.

In various embodiments, controller602may be in electronic communication with load cell604. Load cell604may be disposed in seat pan104. Load cell604may comprise any load cell known in the art, such as a compression load cell, or the like. Load cell604may be configured to measure a weight of an occupant16. Load cell604may be configured to transmit measurements to controller602, thereby providing the measured weight of the occupant16to controller602.

In various embodiments, controller602may receive an ejection command from the ejection handle106. In response to the ejection command, the controller602may command the rocket catapult assembly200to transition from the inactive state to the active state. In response, the motor assembly202may ignite the first cartridge342, the second cartridge344, or both the first cartridge342and the second cartridge344. In various embodiments, when the load cell604measures a weight of an occupant that is less than a first threshold weight, the controller may enable only the first ignitor352. In various embodiments, when the load cell604measures a weight of an occupant that is greater than a second threshold weight, the controller may enable both the first ignitor352and the second ignitor354. When the load cell604measures a weight of an occupant that is between the first threshold weight and the second threshold weight, the controller may enable only the second ignitor. In various embodiments, the first ignitor352is in communication with the first cartridge342and the second ignitor354is in communication with the second cartridge344. The first cartridge342is configured to generate a thrust of rocket catapult assembly200that is less than a thrust generated by the second cartridge344.

In this regard and by controlling which cartridges in the rocket catapult assembly300as a function of an occupant weight, an occupant16of an aircraft12may be ejected at a force based on the weight of the occupant16, as opposed to a maximum weight of an occupant.

With reference now toFIG. 7, a schematic block diagram of a control system700for first ignitor352and second ignitor354is illustrated. In various embodiments, control system700comprises a display switch704, first ignitor352, and second ignitor354. The display switch704may be disposed in a cockpit of aircraft12and electrically or energetically coupled to the first ignitor352via a first electrical switch702and electrically coupled to the second ignitor354via a second electrical switch706. Display switch704may comprise three positions (e.g., an off position, a neutral position, and an on position, or the like). In various embodiments, the first electrical switch702may be configured to enable first ignitor352when display switch704is in a first position or a third position. In various embodiments, the second electrical switch706may be configured to enable the second ignitor354when display switch704is in a second position or the third position. As such, “first position” may correspond to a relatively light weight person, “second position” may correspond to a relatively average weight occupant, and “third position” may correspond to a relatively heavy weight occupant. Display switch704may be manually turned to first position, second position, or third position (i.e., the occupant16manually selects a display switch position based on occupant's weight, which completes the first circuit, the second circuit or both circuits in response).