US2410057A

US2410057A - Parachute

Info

Publication number: US2410057A
Application number: US499306A
Authority: US
Inventors: Leonard P Frieder; Walter S Finken
Original assignee: FRIEDER
Current assignee: FRIEDER
Priority date: 1943-08-20
Filing date: 1943-08-20
Publication date: 1946-10-29
Anticipated expiration: 1963-10-29

Description

Gd# 29, 1946. L, P. FRIEDER E- AL -25410057' PARACHUTE Filed Aug. 20, '1945 WHL TER .sf//vfrE/v erw ATTORNEY Patented Oct. 29, F1946 PARACHUTE 1 -Leonard P.y Frieden Rockville Centre, and Walter S. Finken, Brooklyn,

. or to said `Frieder N. Y.; said Finken assign- Applcation'August 20, 1943, Serial No. 499,306

..6 Claims. I 1

This inventionrelates `to parachutes which =are launched from I airplanes and the like-with loads of various kinds attached and has for its object .the provision of means for insuring quick Vopening of the parachutes. This is always important but it is of particular importance when vthe loads have to be dropped or men have to jump from planes flying at -low altitudes. Parachutes `used for dropping loads are usually folded in some sort of a pack or container-and `heretofore the. apex of the canopy has .been connected to the airplane by a cord so `thatiwhen the pack and the load to be dropped are thrown overboard thecord willdraw the chutefrom the pack and the cord will thenbreak or may. be cast loose. .Trouble has been experienced withsatisfactory operation of the parachutesunder such conditions A.because `when aY parachuteis pulled from its pack by stress `applied at..its apex the canopy will stream and` after release will tend to continue to stream instead of opening. .If the :assembly is dropped from ahigh Aaltitude there may be enoughtime for .this condition.` to correct itself but there is no certaintythat itiwill, and in low altitude operations the streaming and consequent failure to open is a particularly serious defect and causesgreat damage to loads and injury to men because; the drop isnotsucently retarded.

A main object of the inventionris to provide a simple construction and method of` launching parachutes which `will insure quick and proper opening of parachute canopies so that they may be used to drop loads from planes `flying, close to the ground when occasion requires it.

With the foregoing and incidental objects 'in View the invention consists in a novel construction and arrangement f parts.` and a novel method of launching parachutes illustrated in the drawing accompanying and forming a part of the description contained in this specification, the novel features being pointed out in claims appended hereto.

In the drawing the load to be dropped is represented by the package IU. It is tied or secured in any desired way to the shroud lines II of the parachute, only three .of the shroud lines being indicated in the drawing. There are, of course,

varying numbers of shroud lines depending upon ythesire of the parachute and the load to be supported. In the construction illustrated the shroud lines are connected by loops I2 on their .ends passing around a hem cord I3. The hem cord I3 is slidable in a multi-ply hem on the canopy, the hem being constructed and reinforced substantially as shownand described `in U..S. Patent (omai- 149) being opened or released before the apparatus is launched. The parachute is drawnA outl ofthe pack by a static cord or line I4 which is connected in any suitable way to an airplane. When pack is opened and the load and the pack are thrown Voverboard the cord I4 willpull the parachute from'the pack or container. `The cord I4 is provided with a weakened section I5 which will break as soon as the air resistance and/orthe weight of the load is suiiicientlyappliedf tothe cord I4. In the construction shown in the drawing the part lIlla of the cord I4 willl remainat tached to the airplane.

It has been found that by pulling the parachute from its container by force applied to the hem 'the opening ofthe lparachute is greatly facilitated and made much more certain.- This is because it insures an opening of the edge of the canopy which is suiiicient to insure the entrance of air to expand the canopy even though at the time the weakened section .I5 of the cord `lliV breaks the opening has only begun. Usually, however, because of the speed of the airplane, the canopy will snap to a fully opened position at substantially `theinstant the cord I5 breaks. TheA air resistance arising from descent of the load .will further insure the quick `opening and complete expansion of the canopy to give theintended support for the load. There is no chance for the canopy to stream as it is drawn from the-.pack

or afterward and even though theload is dropped from a very low altitude the extremely quick and sure opening of the canopy insures full efficiency in retarding descent ofthe load during `substantially the full period of time required for theload -to land.

The weakened section I5. is preferably a` cord .which has been selected to` have a breaking strength necessary onlyto insure drawing the parachute from its pack and at least starting the opening of thefcanopy. This strength will, of course, vary according to the size of the structure as a wholeand other conditions, and the connection can in effect be calibrated for `particular structures by breaking tests. I

`It is Vpreferred to use a hollow center cord I4 of relatively large ldiameter which can be cut and the smaller cord I5 threaded into the cut ends and` then secured by stitching IE. By `this .construction it is an easy matter to put inthe ,proper` cord I5. m.

The construction shown and described herein has been highly successful in dropping loads and this has been due to the construction described and the method in which the opening of the parachute is started by force applied by the moving plane. It is to be understood that reference to airplanes is not intendedto exclude other forms Vof air vehicles with .which the construction herein described may obviously be used.

While the form of connection shown has advantages and is preferred, it is obvious that the static line or cord I4 may be connected in other ways directly to the hem or edge: or to one of the shroud lines at a point close to said hem or edge. The basic idea is at least to start the opening of the parachute canopy by the temporary application of a stress to the edge or hem of the canopy as an incident to launching the lloaded parachute.

It is also to be understood that the invention can be used in its various phases with parachutes 'which are not packed in containers -or chute 'gpacks. In some instances the chute is folded up on the load and bound in place by .a cord which `is easily broken or which is secured by a slip knot. The static cord may be-connected to break the binding cord or open the slip `knot when the 'unit is clear ofthe plane. Thev weakened section I5 in a static cord I4 is, however, preferably always employed. A light Vcord having the desired strength might be used instead of the cord I4, I5, but because of the construction and greater cross-section of the cord I4 the danger of fouling is much lessthan if only the single light cord should be used.

A Itis sometimes necessary or advisable to discharge a number of parachutes, with loads attached, in tandem or multipley series. In this practice either an unweakened static cord I4 or a weakened static cord I4, I5 may be connected ybetween the hem ofthe rst parachuteV and, for example, the load of the next one and so on for the entire series, the hem of thelast parachute only being connected to the plane by a weakened.

static cord I4, I5. This makes possible a speedy launching of a number of units while insuring that the canopy for each load will open instantly. This idea lcan be utilized to advantage where paratroopersare to be landed from planes iiying at low altitudes. The hem of each parachute can be connected by a weak or weakened static lcord to the next following chutepack or paratroopers and so on for thev series, the hem of the' last parachute being connected to the plane `as previously described.

l The invention is also useful in connection-with signalling devices in which a signal such asY a vlight is supported by a parachute. It is ordinary jpractice to pack the signal and the parachute in -,a container from which the parachute and signal :are discharged, usually by an explosive. Inl this vvembodiment'a weakened static cord I4, I5, may

be connected between the hem of the parachute and a resistance element which-may be a part of the container so that upon discharge the resistance inertia of a freed component part oiV the signal assembly will open the hem of the parachute to admit air under the canopy and break the weak link in the static cord. This is particularly advantageous in instances wherefthe signal and parachuteare vpacked ina small compass and kept packed for a period of time,; resulting in aftendency to crease the material'of the canopy. Even though the materialvmay have been packed solong that there is a tendency'fo'r 4 the creases to take a permanent set, the use of this invention will insure quick and prompt opening of the canopy to support the load.

In'explaining the invention the details of the illustrative embodiment have been gone into at Some length but it is not the intention to be limited by those details except to the extent-indicated inthe claims which follow.

What is claimed is:

1. In an apparatus of the character described, a unit comprising a normally unopened parachute canopy and a load connected by shroud lines to the canopy, and a single static cord directly connecting one point only of the outer edge of the canopy Vto the airplane from which the unit is launched or dropped whereby the interior of the canopy is opened to air resistance, said cord constituting the only connection between the unit and the airplane at the time of launching and being so constructed that it will break under the strain applied by the opening of the canopy and weight of the load. l v

2. In an apparatus of thecharacter described, a unit to be dropped from an airplane comprising a normally unopened parachute canopy and a load connected by shroud lines to the canopy, andk a weakened static `cord secured at one end to one point only of theouter edge of the canopy and at the other end to the airplane whereby the canopy edge will be opened to admit airV under the canopy when theunit is launched and before the weakened static cord breaks under1 strain applied by air resistance on the canopy-and weight of the load, said cord constituting the only connection between the loaded canopy Yand the airplane at the time of said launching.

3. In an apparatus of the character described, a unit to be dropped from an airplane comprising a. normally unopened parachute canopy and a load connected by shroud lines to said canopy, a single static cord connected at one'end to the outer edge or hemof the canopy and secured at its other end directly to the airplane from which the unit is to be dropped, saidlcord comprising two sections of relatively large diameter connected together by a cord section which isvweaker and smaller in diameter than saidrtwo sections and is in axial alignment with said twosections, the weaker cord section being selected according to the size of the canopy and weight of the load', to break by air resistance against the canopy and the load. f

4. In an apparatus of rthel character described, a static line connecting one point only of the hem of a parachute canopy directlyfyto an airplane consisting oftwo spaced apart endY sections of a hollow center 'cord anda smaller7and weaker cord having its ends within said hollow centers and secured against withdrawal from said hollow centers whereby said weaker cord will breakunder strain imposed upon the static line said weaker cord being selected as to size and strength according to the magnitude of the strainY to Vbe resisted before it breaks. f- Y e 5. An apparatusy for dropping loadsirom a moving airplane comprising a normally unopened parachute canopy and a load connected byjshroud lines to the canopy and a static cord secured at one end `to one point only of thejouter edgepf the canopy and connected at its other Venddirectly to the airplane whereby whenthe canopy and itsl'oad Yare launched said cord will pull out the portion of the edge of the canopy t'o whichit is'` secured toj admit air resistance -under fthe canopy, said cord being so constructed that it will break under the strain imposed on it by the air resistance on the canopy, said cord constituting the only connection between the canopy and the airplane at the time the loaded canopy is launched.

6. A method of launching load-carrying para chutes which includes connecting one point only of the edge or hem of the parachute directly to an airplane which is in flight in such a manner 6 that When launched the edge or hem of the canopy is pulled out by said connection to admit air under the canopy, launching the parachute and its load, and utilizingthe air resistance against the opening canopy to break the connection between the canopy and the airplane.

LEONARD P. FRIEDER. WALTER S. FINKEN.