US3493199A

US3493199A - Autorotating parachute

Info

Publication number: US3493199A
Application number: US668975A
Authority: US
Inventors: Abraham Flatau
Original assignee: Individual
Current assignee: Individual
Priority date: 1967-09-19
Filing date: 1967-09-19
Publication date: 1970-02-03
Anticipated expiration: 1987-02-03

Description

Feb. 3, 1970 FLATAU 3,493,199

AUTOROTAT ING PARACHUTE Filed Sept. 19, 1967 2 Sheets-Sheet 1 Fig] -2 F /g. 2 PRIOR ART INVENTOR. Abra/ram F lafau A T TORNE Y3 Feb. 3, 1970 A. FLATAU AUTOROTATING PARACHUTE 2 Sheets-Sheet 2 Filed Sept. 19, 1967 Fig.6

Fig. 5

Fig. 4

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ATTORNEYS INVENTOR Abraham F lafau United States Patent 3,493,199 AUTOROTATING PARACHUTE Abraham Flatau, PO. Box 657, Joppa, Md. 21040 Filed Sept. 19, 1967, Ser. No. 668,975 Int. Cl. B64d 17/14, 17/18 U.S. Cl. 244145 8 Claims ABSTRACT OF THE DISCLOSURE A parachute comprising a plurality of circumferentially positioned canopy apertures or vents correspondingly covered by canted stand-off panels which are the means of effecting the rotation of the canopy with respect to the attached load. The rotation is achieved by varying the degree of canting of the stand-off panels and thereby eifecting both the rate and direction of turning of the parachute which can be predetermined as clockwise or counterclockwise.

The parachute canopy design with the canted stand-off panel transfers a portion of the air flow energy into canopy rotation.

The invention described herein may be manufactured, used, and licensed by or for the Government for governmental purposes without the payment to me of any royalty thereon.

Reference is made to my copending application Ser. No. 661,474, filed Aug. 17, 1967, Parachute With Canopy Vent and Stand-Off Panel.

This invention relates to novel parachute canopy designs, and, more particularly to parachutes possessing superior stability and drag characteristics by means of its autorotating performance.

An object of my invention is to provide a parachute canopy design embodying a canopy aperture means covered with a canted stand-01f panel which transfers a portion of the air flow energy into canopy rotation.

The Vortex-Ring Autorotation Parachute of Barish, U.S. Patent No. 2,797,885, is exemplified by FIGURE 1. The canopy 2 is comprised by a plurality of segmented panels 11 secured at the vertical axis at 12, and segmented space 13 between the adjacent said panels. The marginal edges of the panels may be connected peripherally together by chords 14 being attached to the shroud lines 4. Each panel 11 has a small windmilling section 15, partially or wholly removed from the panel. Each small windmill is supported across the segmented space 13 between the panels.

The interest in slowing the rate of fall of a body from the point of release into the fluid medium has greatly increased during recent years with our increased interest in outer space. There are several requirements for decelerators with greater emphasis being imposed on certain performance characteristics over other needs. But one essential action common to all decelerators is the slowing down of the falling body to such a velocity that its impact with the surface cause little or no damage to the payload. In attempting to achieve the aforementioned essential action, the parachute must have sufficient drag characteristics as a falling body. The rotation of the parachute canopy provides the higher drag coeificients over the nonrotating type. In addition, the rotational performance can improve the parachute stability markedly.

My studies provided for the departure from the usual or traditional canopy designs. This investigation led to the use of a canopy aperture superimposed with a canted stand-off panel which transfers the air flow energy into a form of rotation. The present invention embodies a plurality of circumferentially positioned canopy apertures or vents correspondingly covered by canted stand-off panels which are the means of eifecting rotation of the canopy with respect to the attached load. The rotation is achieved by varying the degree of canting of the stand-off panel in relation to the canopy panel and thereby effecting both the rate and direction of turning of the parachute. The direction of the rotation can be predetermined as clockwise or counterclockwise.

The concept of autorotating the parachute utilizing the canted stand-off panel and canopy aperture combination is applicable to other commercially available parachutes.

These and other objects and features of my invention will appear from the following description thereof in which reference is made to the figures of the accompanying drawings.

In the drawings:

FIGURE 1 represents a schematic elevation of the Vortex Ring Parachute of Barish, U.S. Patent No. 2,797,885.

FIGURE 2 is a plan view of a prior art parachute fokrlmed by two rectangular strips at right angles to each ot er.

FIGURE 3 is similar to view of FIGURE 2 embodying my invention of the stand-off panel superimposed on the canopy aperture.

FIGURE 4 is a perspective view partly in section of FIGURE 3 along line 4-4 showing stand-off panel in its extended position during normal descent of the parachute.

FIGURE 5 is a diagrammatic side elevation of FIG- URE 4.

FIGURES 6-7 are diagrammatic side elevation of alternative forms of the stand-otf panel.

FIGURES 8-9 are diagrammatic side elevations of further alternative embodiments showing a fragment of the stand-off panel.

FIGURE 10 is a perspective view of a parachute fabricated in accordance with the present invention in an inflated condition.

During the trajectory movement of the parachute, the force of air below the parachute, or whatever air pressure the parachute encounters during initial opening and its descent, causes the stand-off panel over the aperture to automatically open and remain extended under the same conditions as does the canopy, and in addition, the said panel assumes a cambered configuration. The air flow striking the canted stand-off panel during the parachutes deployment in FIGURES 4l0 creates an angular rotation of the canopy in a counterclockwise direction. The arrows in aforementioned figures indicate the direction of air flow. A portion of the air thus confined beneath the parachute moves through the canopy aperture 6 and strikes the canted stand-off panel creating the force to bring about autorotation of the canopy by the change in the linear momentum of the fiow. It is also to be understood that some of the air fiow penetrating the open sides between the canopy surface and the stand-off panel may also produce a portion of the force to cause autorotation of the canopy. The configuration of the canopy aperture and canted stand-off panel formed by the flexible tie lines are designed to control the flow of air that passes out through the parachute to the atmosphere effecting the rate of rotation, the magnitude of the drag force, and at the same time improving the stability during its descent.

The dimensions of the canopy aperture and canted stand-01f panel may be varied. A parachute canopy utilizing two panels at right angle to each other were employed in my studies. In these studies, the preferred results were obtained where there were four cut-out sections or canopy apertures equally positioned circumferentially in the canopy. The canted said panel is always equal to the same dimensions as the canopy aperture or it may be larger. The center line of the canopy aperture is preferably spaced on a vertical line equidistant between the border edges of each rectangular panel or gore. It is to be understood that the panel length may vary. For example, the length of each rectangular panel may vary from 18 to 36 inches. The associated dimensions of the canopy aperture and stand-off panel are longitudinally from about 3 to 7 inches in length on the side parallel with the long edge of the rectangular arm are laterally from about 2.5 to 5.5 inches in width and positioned from 1 to 3 inches in the section parallel and adjacent to the skirt.

The alternative configuration embodies the concept of an overlap of the stand-off panel in relationship to the cutout section in the canopy. The overlap comprises increasing the lateral dimensions and a concomitant increase in the longitudinal dimension downstream of the stand-off panel. The effect of this modification is to provide additional flow control by varying the air channeling means. In this manner, the flow through the Channeling means will be less subject to immediate tripping or separation which would reduce or lessen the flow control.

FIGURE 2 is a particular basic parachute configuration which is a canopy 2 formed by two rectangular strips at right angle to each other and having suspension lines 4 attached along the marginal edges of each arm of the said canopy.

In the forms of my invention illustrated in FIGURES 3-10, the parachute embodies a canopy planform 2 formed by two rectangular strips at right angles or normal to each other with a plurality of canopy apertures 6 and corresponding plurality of stand-off panels 8 and shroud lines 4 running along the outside edge of the rectangular strip or panel uniting at a focal point. The scope of this invention is intended to include two or more canopy apertures and their corresponding stand-off panels in each arm of the canopy. However, the preferred embodiment is a single canopy aperture with its single standoff panel for each panel or gore.

FIGURE 3 is similar to FIGURE 2 with the added feature of illustrating the stand-off panel 8 superimposed on the canopy aperture 6.

FIGURE 5, the side elevation view of FIGURE 4, describes the canted stand-off panel 8 in its fully extended position after parachute deployment with the flexible tie lines attached between each corner of the stand-off panel and the corner of the canopy aperture. The said panel is canted by adjusting the tie lines in order to contract the distance along one longitudinal side between the said panel and said aperture. FIGURE 6 illustrates a greater degree of canting than in FIGURE 5. The air flow has four avenues of movement as shown by the arrows. Each stand-off panel is canted on the downstream side in the direction of rotation.

FIGURE 7, similar to FIGURES 4-6, illustrates the complete canting of the stand-off panel 8 such that the side of the said panel downstream is now directly attached to the corresponding side of the canopy aperture 6. In this configuration, there are three routes of air flow control.

FIGURE 8 illustrates the modification of FIGURES 4-6 embodying the use of parachute fabric forming an inclosure means on three sides between the stand-off panel 8 and canopy aperture 6. The said enclosure includes entire longitudinal downstream side, the side parallel and adjacent to the skirt of the canopy, and the side diametrically opposite the said side parallel and adjacent to the skirt. In this configuration only one air flow control means is available being the side parallel to the said longitudinal downstream ride.

FIGURE 9 illustrates the modification of FIGURE 7 of the fully canted stand-off panel 8. There are two enclosing fabric means which are the side parallel and adjacent to the skirt of the canopy and the side diametrically opposite the said side parallel and adjacent to the skirt. The border forming the inclined plane of the canted panel is directly attached to the canopy panel. There is only one avenue of air flow control.

FIGURE 10 illustrates the parachute fabricated in accordance with the present invention after depolyment with a swivel 16 attached between the focal point of the shroud lines and the attached load 17. A peripheral line 18 may be employed, if desired, to attach each panel as to maintain the proper attitude relationship through the rotational plane.

Although for description purposes FIGURES 49 are examples of the principle of shaping the stand-off panel, this is not to be construed as the only canting configurations. It is within the scope of this invention that the said panel be inclined by adjusting the tie lines downstream immediately below the parallel plane of the said panel in relation to the canopy to the direct attachment to the canopy.

In the construction of the parachute, the canopy fabric and the stand-off panel may consist of the following materials: linen, silk, cotton, jute hessian, paper cellulose acetate fabric, viscose or cuprammonium rayon fabric, nylon, and other synthetic fibers.

While I have shown and described by invention, it is to be understood that various changes in the shape, size and arrangement of parts may be resorted to without departing from the scope and spirit of the invention.

I claim:

1. An autorotating parachute comprising a canopy comprising a plurality of panels, each panel comprising at least one circumferential canopy aperture covered by a stand-off panel, the sides of the stand-off panel being substantially co-extensive with its canopy aperture in inflated position, each said aperture having parallel sides and each positioned inwardly from the skirt and bordered by the material of each panel along each side of said aperture, the lower side of said aperture being adjacent to the skirt area of said canopy, said stand-off panel canted outwardly in a transverse manner from the leading edge portion of the stand-off panel to the trailing edge portion of the stand-off panel, each stand-off panel being canted in the same circumferential direction and separate exterior meains fixedly securing the stand-off panel to the edges of the canopy aperture.

2. An autorotatable parachute comprising a canopy comprising two rectangular strips at right angles to each other with shroud lines running along the longitudinal edges of each strip and combining at a focal point, each panel comprising one circumferential canopy aperture covered by a stand-off panel, the sides of the standoff panel being substantially co-extensive with its canopy aperture in inflated position, each said aperture having parallel sides and each positioned inwardly from the skirt and bordered by the material of each panel along each side of said aperture, the lower side of said aperture being adjacent to the skirt area of said canopy, said stand-off panel canted outwardly in a transverse manner from the leading edge portion of the stand-off panel to the trailing edge portion of the stand-off panel, each stand-off panel being canted in the same circumferential direction and separate exterior means fixedly securing the stand-off panel to the edges of the canopy aperture.

3. A parachute as recited in claim 1, in which the said exterior means are flexible extending between the said incline plane of the stand-off panels and said each panel, there being openings between the said incline plane of the stand-off panels and said canopy apertures permitting the flow of air.

4. A parachute as recited in claim 2, in which the said exterior means are flexible joining the edges of the said canopy aperture to the edges of the corresponding covering said stand-off panel, permitting avenues of the flow of air between the said canopy aperture and corresponding stand-off panel.

5. A parachute as recited in claim 4, in which the said exterior means join each corner of the said canopy aperture to the corresponding corner of the covering stand-off panel.

5 6. A parachute as recited in claim 5, in which the said longitudinal downstream side of the stand-off panel forming the incline plane is directly attached to the border of the corresponding canopy aperture.

7. The parachute as recited in claim 4, in which the said exterior means form an enclosure with contiguous canopy fabric joining the canopy aperture sides to the covering stand-01f panel corresponding sides, the said enclosure consisting of (a) said entire longitudinal downstream side of the stand-off panel (b) side parallel and adjacent to the skirt of the canopy (0) side diametrically opposite the said side parallel and adjacent to the skirt.

8. The parachute as recited in claim 4, in which the said exterior means form an enclosure with contiguous canopy fabric joining the canopy aperture sides to the covering stand-off panel corresponding sides, the said enclosure consisting of (a) side parallel and adjacent to the skirt of the canopy (b) side diametrically opposite the said side parallel and adjacent to the skirt and the 3,228,637 1/1966 Gross 244152 3,331,573 7/1967 Winker et a1 244145 FOREIGN PATENTS 253,070 7/ 1964 Australia.

MILTON BUCHLER, Primary Examiner T. W. BUCKMAN, Assistant Examiner US. Cl. X.R. 244152