Patent Application
20160288914
The present disclosure relates to parachutes, and, more specifically, to a drogue parachute having selectively reduced surface resistance.
During ejection events, an ejection seat may be propelled from a cockpit. A parachute system may then be employed to reduce the air velocity of the ejection seat and deliver the seat safely to land or sea. Drogue parachutes may deploy rapidly in response to the seat ejecting from the cockpit. The drogue parachute may decelerate and stabilize the ejection seat to enable safe deployment of a main parachute. In some instances, with heavier aircrew, for example, the clearance between an ejecting seat and the passing tail of an aircraft may be minimal. A drogue parachute pulling the seat aft, towards the tail of the aircraft, may cause a collision between the drogue chute and the tail of the aircraft or the ejecting seat and the tail of the aircraft.
A drogue parachute may comprise a bridle, suspension lines coupled to the bridle, and a canopy coupled to the suspension lines. The canopy may comprise a first side with a lower air resistance than a second side opposite the first side.
In various embodiments, the first side comprises a mesh portion configured to reduce drag. The first side may also comprise an opening configured to reduce drag. The first side may further comprise a low resistance portion in a circular or rectangular configuration. The bridle and the suspension lines may be configured to direct the first side in a predetermined direction, such as downward. The low-resistance structure may comprise an area ranging from 10 to 400 square inches.
An aircraft ejection system may comprise a seat, a bridle coupled to the seat, suspension lines coupled to the bridle, and a drogue canopy coupled to the suspension lines. A first side of the drogue canopy may have a lower drag than a second side of the drogue canopy.
In various embodiments, the first side may comprise a mesh portion configured to reduce drag on the first side. The first side may also comprise an opening configured to reduce drag on the first side. The first side may further comprise a low-resistance structure in a circular or rectangular configuration. The bridle and the suspension lines may be configured to direct the first side of the drogue canopy in a predetermined direction. The predetermined direction may be downward. The low-resistance structure may comprise an area ranging from 10 to 400 square inches. The low resistance structure may comprise a mesh material.
The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, the following description and drawings are intended to be exemplary in nature and non-limiting.
The subject matter of the present disclosure is particularly pointed out and distinctly claimed in the concluding portion of the specification. A more complete understanding of the present disclosure, however, may best be obtained by referring to the detailed description and claims when considered in connection with the figures, wherein like numerals denote like elements.
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 exemplary embodiments of the disclosure, 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 limitation. 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 attached, fixed, 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 suspension lines may be used throughout the figures to denote different parts but not necessarily to denote the same or different materials.
As used herein, “aft” refers to the direction associated with the tail (e.g., the back end) of an aircraft, or generally, to the direction of exhaust of the gas turbine. As used herein, “forward” refers to the direction associated with the nose (e.g., the front end) of an aircraft, or generally, to the direction of flight or motion.
With reference to
With reference to
In various embodiments and with reference to
With reference to
In that regard, air in drogue canopy 120 may have less surface on low-resistance side 124 to interact with and may escape drogue canopy 120 more easily than at other locations on the canopy. Similarly, low-resistance side 124 of drogue canopy 120 may also include a lower skin resistance than other locations on drogue canopy 124. Additionally, low-resistance side 124 may have a lower form resistance (i.e., resistance created by the shape of the drogue canopy) than other portions of drogue canopy 120. When deployed, drogue canopy 120 may be configured with low-resistance side 124 directed downward (i.e., towards the aircraft from which a seat is ejected, as illustrated in
With reference to
With reference to
Benefits and other advantages have been described herein with regard to specific embodiments. Furthermore, the connecting suspension lines shown in the various figures contained herein are intended to represent exemplary functional relationships and/or physical couplings between the various elements. It should be noted that many alternative or additional functional relationships or physical connections may be present in a practical system. However, the benefits, advantages, and any elements that may cause any benefit or advantage to occur or become more pronounced are not to be construed as critical, required, or essential features or elements of the disclosure. The scope of the disclosure is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.” Moreover, where a phrase similar to “at least one of A, B, or C” is used in the claims, it is intended that the phrase be interpreted to mean that A alone may be present in an embodiment, B alone may be present in an embodiment, C alone may be present in an embodiment, or that any combination of the elements A, B and C may be present in a single embodiment; for example, A and B, A and C, B and C, or A and B and C.
Systems, methods and apparatus are provided herein. In the detailed description herein, references to “various embodiments”, “one embodiment”, “an embodiment”, “an example embodiment”, etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described. After reading the description, it will be apparent to one skilled in the relevant art(s) how to implement the disclosure in alternative embodiments.
Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. 112(f), unless the element is expressly recited using the phrase “means for.” As used herein, the terms “comprises”, “comprising”, or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
