US 3855930 A
The disclosure relates to an improved miniature rocketry system used for propelling a signal flare and includes a pair of generally tubular shaped housings in telescoped engagement, wherein is disposed a propulsion charge, a propulsion charge ignitor, a delay train or timing fuse, a signal display flare and means for insuring complete combustion of all the pyrotechnics. A nozzle structure is provided at one end of the housing to impart a gyroscopically spin stabilized guidance to the rocket trajectory, and an improved propellant spacer is interposed between the nozzle structure and the propulsion charge for the purpose of separation of the members and retention of the propulsion charge during combustion thereof.
Description (OCR text may contain errors)
mama States Patent [1 1 Mulich et a1.
[451 Dec. 24, 1974 PERSONNEL DISTRESS SIGNAL  Inventors: Stephen F. Mulich, San Ramon; Donald R. Duffy, Dublin; Steven J. Salter, Walnut Creek, all of Calif  US. Cl 102/344, 102/356, 102/376  Int. Cl. F421) 13/40  Field of Search 102/343, 34.5, 34, 49.3, 102/344, 35.6, 37.6
[5 6] References Cited UNITED STATES PATENTS 24,468 6/1859 Lanergan 102/34 53,933 4/1866 l-lale 102/343 2,606,495 8/1952 Clauser et a1 102/354 X 2,785,632 3/1957 Clauser et a1 102/344 2,820,410 1/1958 Tarr 60/35.6 RS 3,135,200 6/1964 Jackson 102/28 3,185,018 5/1965 Damon et al. 236/20 R 3,348,445 10/1967 Nadel 86/1 R j 44 4 /Z W J// 3,367,113 2/1968 Mainhardt 102/343 FOREIGN PATENTS OR APPLICATIQNS 919,871 3/1947 France 102/34 Primary Examiner-Robert F. Stahl Attorney, Agent, or FirmHarness, Dickey and Pierce 57 1 ABSTRACT The disclosure relates to an improved miniature rocketry system used for propelling a signal flare and includes a pair of generally tubular shaped housings in telescoped engagement, wherein is disposed at propulsion charge, a propulsion charge ignitor, a delay train or timing fuse, a signal display flare and means for insuring complete combustion of all the pyrotechnics. A nozzle structure is provided at one end of the housing to impart a gyroscopically spin stabilized guidance to the rocket trajectory, and an improved propellant spacer is interposed between the nozzle structure and the propulsion charge for the purpose of separation of the members and retention of the propulsion charge during combustion thereof.
25 Claims, 3 Drawing Figures PERSONNEL DISTRESS SIGNAL RELATED APPLICATION Reference may be had to the Robert Mainhardt et al. application, Ser. No. 694,208, filed Dec. 28, 1967, now abandoned for Rotatable Rocket Having Means for Preventing Flameout Due to Centrifugal Force Created During Rotation Thereof for a disclosure of a rocket over which the rocket of the present invention has improved features.
BACKGROUND OF THE INVENTION Heretofore miniature rocketry propellant systems have been unable to function universally with a reliability that was commercially acceptable. For a miniature rocket, carrying a useful payload to achieve the desired flight trajectory, the propulsion system must provide a variety of functions which commence with proper propellant ignition. After the propellant is ignited, a suitable chamber pressure and burn rate relationship must be maintained for the purpose of initiating and sustaining rocket propulsion until the desired trajectory is obtained.
One of the problems associated with reliability is the fact that the conventional propellant ignitors used in miniature rocketry systems are limited to propellant ignition capabilities restricted to a narrow range of temperature extremes and other environmental conditions. At low temperatures, for example, in conventional propellant systems, the chamber pressure is lower prior to ignition thereby causing a lower chamber pressure during propellant combustion. Furthermore, the burning rate of the conventional propellant isslower, thereby affording a propellant combustion pressure which has been found to be inadequate. Conversely, in conventional propellant systems when high temperature environmental conditions are experienced, the chamber pressures, along with the extremely high temperature produced by propellant combustion exceed optimum conditions. which often results in motor casing failure.
At extremely low temperatures, motor casing failure may also be experienced which may be attributed to a splitting of the propellant due to the cold. If the propellant is fractured, a greater surface area than is desirable is available for combustion which also may result in excessive chamber pressures of a sufficient magnitude to burst or split the motor casing. Thus the problem involves obtaining propellant combustion which will not over-pressurize at high temperatures, nor underpressurize at low temperatures. Further for propellant combustion to occur reliably over a broad temperature range, a combustion pressure sensitizer is necessary for lower and higher temperature extremes. Most conventional ignition materials however have been found to be pressure sensitive. In the subject miniature rocketry system the ignition energy is supplied from a material which is sufficiently pressure insensitive to provide similar combustion characteristics at many extremes of temperature.
A further problem of previous rocketry propellant systems resides in the propellant spacer component nominally located between the propulsion charge and the nozzle structure. This component serves the dual purpose of retaining the propulsion charge or propellant during combustion while also serving to separate the nozzle casing from the propellant. Previous designs were susceptible to being installed backward which prevented the spacer from functioning as intended. Also previous designs did not reliably retain the propellant.
To overcome the lack of retention, previous rocketry systems employed guiding prongs which were attached to the inside of the motor casing for the purpose of retaining the propellant during propellant combustion. By these means, however, the propellant was found to disintegrate prematurely, drop into the propellant passageway. and clog the nozzle port; thereby causing propulsion failure. The origin of this failure was directly attributable to the guide prongs in the motor casing. Hence, a need was created to design an improved spacer element.
SUMMARY OF THE INVENTION This invention relates generally to rocket-like devices and, more particularly to a rocket propelled device for projecting a personnel distress flare to an altitude such that the combustion of said distress flare will provide an aerial pyrotechnic display.
It is accordingly a general object of the present invention to provide new and improved rocket propelled signal flare.
It is a more particular object of the present invention to provide a propellant ignition capability in a miniature rocket for use in any natural environment.
It is still a more particular object of the present invention to provide a distress signal which may be carried, along with a launching means, on a person without impeding his movement and in such a manner as to be comfortably worn.
It is another object of the present invention to provide a means of environmentally protecting a miniature flare rocket, while improving the overall rocketing functioning including altitude and display duration.
It is yet another object of the present invention to provide a new and improved miniature rocket signal flare of the above character which is of simple design, is easy to assemble, and economical to commercially manufacture.
Other objects and advantages of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING FIG. 1- is a longitudinal cross sectional view of a personnel distress signal in accordance with a preferred construction of the present invention;
FIG. 2 is a transverse cross sectional view taken along the line 22 of FIG. 1; and
FIG. 3 is a transverse cross sectional view taken along the line 33 of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT With reference now to the drawings, a personnel distress signal, generally designated by the numeral 10, is shown as comprising a flare assembly 12 for providing a pyrotechnic display, and a motor assembly 14 for providing the guidance and propulsion capability.
The flare assembly 12 is located on the right end of the personnel distress signal 10 as viewed in FIG. 1, and is comprised of a flare cup 16 wherein is disposed a signal flare pellet 18 and a suitable flare pellet ignitor 20.
The flare cup 16 is preferably constructed from a material having a high resistance to oxidation and suitable to be impact extruded. Aluminum has been found to exhibit these qualities and also is capable of burning with the flare pellet 18 which provides an additional benefit by contributing to the illumination. Other useful materials include, but are not limited to, various plastics and magnesium.
The flare cup 16 itself is comprised of an arcuate shaped forward end wall 22 wherefrom its outer periphery is rearwardly extended an elongated tubular skirt 24. The arcuate shape of the end wall 22 is adapted to approach the form of that of an ogive which has been found to be the optimum configuration for promoting foliage penetration and increasing the overall flight characteristics of the rocketry system thereof. With respect to increased flight characteristics the ogive shape has been found to produce less aerodynamic drag which therefore affords higher altitudes.
To assure total combustion of the flare pellet 18, the rate of combustion is inhibited by restricting the combustion area. This inhibition is accomplished by an elongated paper tube 26, cut perpendicularly at both open ends, and having an outside diameter slightly less than the inside diameter of the skirt 24 of the flare cup 16 to accommodate insertion therewithin. Prior to insertion, the paper material is preferably coated with a resin like substance to prevent an accordian effect of the paper tube 26 at the time of flare pellet compaction as shall become apparent as this specification proceeds.
When the flare cup 16 is used without a paper tube 26, it has been found that the flare cup is consumed at a faster rate than is the flare pellet l8, and as a result thereof the sides of the flare pellet begin igniting. The heat absorbed by the flare pellet 18 at the sides and in front of the burning surface weakens the flare pellet 18 causing the pellet to retain a low strength characteristic in the heat zone. As the flare cup isspinning, flare pellet combustion occurs simultaneously. Therefore, by weakening the flare pellet in the heat zone, the burning surface tends to fly off thereby extinguishing the flare pellet prematurely. Premature extinguishing of the flare pellet is believed to occur with greater frequency at the interface between the flare pellet contractions that at other areas of the flare pellet 18.
The flare pellets 18 are adapted to provide a variety of distress signals depending on the composition of the pyrotechnic material inserted into the flare cup 16. Examples include infrared, ultraviolet, explosive smoke, strip-markers, beacons, or balloons. The desired flare pellets 18 are initially prepressed to volume before being inserted into the flare cup 16. The flare pellets 18 are then further compacted to conform to the shape of the flare cup with a recessed concave area 27 located at its rearward surface wherein is centrally disposed the flare pellet ignitor 20, such as black powder or the like. The flare pellet ignitor is correspondingly prepressed to shape prior to insertion into the concave area 26 of the flare pellet 18, and further compacted upon insertion to correspond to an inward concave surface thereof.
The motor assembly 14 is comprised of a motor and delay housing 28 wherein is disposed a nozzle structure 30, a propellant spacer 32, a propellant cartridge 34, a
propellant cartridge ignitor 36, and a delay train or time fuse 38.
The motor and delay housing 28 is preferably constructed from a machinable metal, such as steel, which is capable of containing propellant combustion pressures without rupturing. To the finished housing 28 a protective coating, such as cadmium, is applied to provide environmental protection.
The motor and delay housing 28 is a generally tubular shaped member having a necked down forwardly extended portion 42 integrally connected to an enlarged elongated tubular rearward casing by means of an annular forwardly inclined intermediary wall 44. The forward portion of the rearward casing 40 is radially undercut providing an elongated radial joining surface 45 rearwardly terminating with an exterior annular shoulder 46 which is adapted to receive and suitably locate in a telescopic bonding manner the inner radial surface and rearward end of the flare cup respectively. The rearward casing 40 is further provided with an internal annular shoulder 48 by means of a counterbore 50 disposed at the rearward end of the rearward casing 40.
The necked down forwardly extending portion 42 is tapered at its forward end as shown at 52 for engaging the inward concave area 27 of the flare pellet 18 as shown in FIG. 1. An inwardly radially extending lip 54 is disposed at its rearward end thereof defining an orifice 56 wherefrom the forward face 58 extends radially outwardly and forwardly.
With reference now to the rearward end of the motor and delay housing 28, the enlarged elongated tubular rearward casing 40 is substantially closed by the transversely extending nozzle structure 30. The nozzle structure 30 is formed with an annular chamfer 60 around the rearward outer periphery thereof and is adapted to be fixedly secured within the rearward end of the casing 40 by having the end of the casing 40 swagged or deformed radially inwardly into engagement with the periphery of the annular chamfer 60 as seen at 62 in FIG. 1.
The nozzle structure 30 is formed with a plurality of discharge orifices (not shown) equally circumferentially and radially spaced therearound. The function of the discharge orifices is to impart a gyroscopically spin stabilized propulsion and guidance to the rocket trajectory of the personnel distress signal 10. Reference may be had to US. Pat. Nos. 3,490,121; 3,437,289; 3,419,230; and 3,367,112 assigned to the assignee of the present invention for a disclosure of suitable nozzle and nozzle assemblies contemplated for use in this invention.
The nozzle structure 30 is provided with a centrally located primeror similar type ignition device which is fixedly mounted within a suitable primer seat or opening 64 formed in the structure 30. Extending across the interior or forwardmost side of the nozzle structure 30 is a relatively thin, preferably rupturable, diaphragm member 66 that is fabricated of a relatively thin sheet of aluminum which may, for example, be secured to the forward side of the nozzle structure 30 by a suitable pressure or heat sensitive adhesive. The diaphragm 66 functions both as a hermetic seal for the rearward end of the personnel distress signal 10, and to facilitate pressure buildup internally of the motor and delay housing 28 upon firing of the primer 64.
An annular recess 61 is provided slightly inward from the rearward face of its nozzle structure 30 wherein an appropriate sealer such as humiseal is disposed for the purpose of retaining the propellant cartridge vapor at extreme temperature ranges. A second type of sealer, such as phenol formaldehyde, is preferably used to seal the primer 64 to the nozzle structure 30 as indicated at 63, due to the corrosive action of humiseal on the primer 64. The sealant at the joint where the motor casing 40 is swagged to hold in-the nozzle structure 30 indicated generally at 67 may be either humiseal or phenol formaldehyde, or their equivalent.
-Disposed within the rearward end of the casing 40 immediately forwardly of the diaphragm 66 is the propellant spacer 32. The propellant spacer 32 is comprised of an annular web portion 68 integrally engaged to a radial flange 70 having an outside diameter preferably adapted to be snugly received within the counterbore 50 and suitably positioned by the annular shoulder 48. The annular web portion 68 has a central aperture 72 and equal axial portions of the radial flange 70 project from both sides of the web portion 68.
The propellant spacer 32 functions to separate the propellant cartridge 34 from the nozzle structure 30, and to retain the propellant cartridge 34 during propellant combustion. Because the propellant spacer 32 is symmetrical axially from the web portion 68, it may be installed without regard to a rearward or forward axial direction. Previous spacers which had to be referenced by a forward or rearward end were often installed backwards, which led to a malfunction of the personnel distress signal during operation. It will be appreciated that the nozzle structure 30 contains nozzle ports which would be covered by the propellant of the propellant cartridge 34 if the propellant spacer 32 was functioning improperly or was not present, whereby the covering of the nozzle ports would hinder or prevent proper rocket propulsion.
Further disposed within the rearward end of the casing axially adjacent and forwardly from the propellant spacer 32 is a quantity of propellant which may be of any suitable type known in the art. In the preferred embodiment the propellant cartridge 34, manufactured in spaghetti form, and guillotined to size for insertion within the propellant housing casing 40. The propellant cartridge 34 is generally cylindrically shaped having a central bore or passage 73 disposed therewithin its central axis for the purpose of receiving the propellant cartridge ignitor 36. Preferably the outer diameter of the cartridge 34 is substantially the same size as the inner diameter of the housing 28 whereby to preclude any relative movement therebetween upon assembly of the personnel distress signal 10.
The propellant cartridge ignitor 36 is disposed in the central bore or passage 73 and comprised of a composition of a mixture of finely ground (flour like consistency) 95/5 percent boron barium chromate and a composition of granulated boron potassium nitrate mesh 12/20. A combustion characteristic of boron barium chromate .is a low gas output whereas a combustion characteristic of Boron Porassium Nitrate is a burning rate which is insensitive to combustion pressure. This has been found to be very beneficial at low environmental temperatures where the gas pressures are too low for successful propellant combustion without the boron barium chromate, while with high environmental temperatures the boron barium chromate does not contribute sufficient gas pressures to cause motor casing failure. Thus at low temperatures the heat requirement of the propellant is satisfied by the boron potassium nitrate while at high temperatures the propellant pressures are not increased by the rate of boron potassium nitrate burn. Consequently, with the use of boron barium chromate and boron potassium chromate in effective combination there is obtained an ignitor composition, which when combusted over the environmental extremes, delivers sufficient heat to the propellant surface and generates suitable chamber pressure so that propellant ignition is reliably achieved.
With reference now to the necked down portion 42, located at the forward end of the motor and delay housing 14;, the delay train or timing fuse 38 of pressed combustible material is disposed therewithin.
The delay train or timing fuse 38 may be of any suitable material adapted to burn at a preselected rate, whereby to function in igniting the flare ignitor pellet 20 which in turn ignites the flare pellet l8 ata preselected time after ignition of the propellant cartridge 34, as will later be described. The rearward face of the timing fuse 38 has a concave recessed portion 74 commencing slightly inward from the inside diameter of the projecting lip 54 for the purpose of improving the containment of the reaction products in the combustion zone, and also to assure the complete burn of the timing fuse in a more certain manner. In previous designs utilizing an oblate face, it was found that the ignition of the delay train material produced conditions which could cause a flaking off of the delay train material and result in a cessation of combustion.
A second concave recess portion 76 is preferably similarly provided in the forward face of the timing fuse 38 being generally larger than the recess 74 in rearward wall. By manufacturing the forward end in a similarly recessed manner, the heat from combustion in the re cessed area of the delay train is transferred to the flare ignitor assuring reliable ignition.
In accordance with the principles of the present in vention the forward necked down portion 42 is provided with means adapted to prevent the material of the timing fuse 38, which transforms to a semi liquid state as it burns toward the flare pellet 18, from being thrown or forced out of the rearward end of the necked down portion 42 under the influence of centrifugal force due to rotation of the personnel distress signal 10 during its forward propulsion. The means is provided by the radially inwardly extending lip 54 which defines the centrally located restricted discharge orifice 56.
[n the preferred construction of the present invention the extending radial lip 54 encloses approximately one half of the inside diameter of the necked down portion 42 with the result that the diameter of the restricted orifice 56 is approximately one half the inside diameter of the necked down portion 42. It may be noted that the relative size of the necked down portion 42 with respect to the diameter of the orifice 56 may be varied in accordance with the type of material comprising the timing fuse 38.
From the above description, it will be seen that upon ignition of the timing fuse 38, the extending radial lip 54 will prevent the rearwardmost part of the timing fuse 38 from being forced outwardly through the discharge orifice 56 as the personnel distress signal 10 rotates or spins while it is projected forwardly. Accordingly, the timing fuse 38 upon being initially ignited,
will burn smoothly and continuously for a predetermined amount of time prior to effecting ignition of the flare pellet 18, with the possibility of a flameout of the timing fuse 38 being positively prevented.
, A further preferred feature of the present invention is the use of certain chemical coatings on designated areas of the personnel distress signal rocket to enhance the operational life of the signal and surprisingly to contribute to the flare function.
Materials susceptible to deterioration when exposed to climate or environmental conditions are used in the personnel distress signal construction. These materials must be protected against such deterioration to the extent that total rocket flare function is not impaired. The protection in the form of a chemical coating useful in the present invention has the added characteristic of not cracking, chipping, or scaling with age, or extremes of climatic, or environmental conditions.
Humiseal is a trademark of Columbia Technical Corporation for a polyurethane which exhibits desirable properties for a continuous use range from 70 to 250F, is fungus resistant and resistant to solvents. These characteristics are essential to a flare rocket useful in any natural environment.
Humiseal is applied by dipping or spraying to the outside area of the flare cup 16, and the flare cup motor assembly mating joint of the skirt 24.
Another essential feature of the present invention concerns the use ofa paint coating by. dipping or spraying on the flare cup 12 and motor assembly-flare cup joint 45. The paint applied to the personnel distress signal 10 serves two purposes. The first is to provide environmental protection to the round. The second is somewhat more subtle but equally important inthat it retards the spin rate thereby permitting increased burn time from the pyrotechnic flare 12. As the motor assembly 14 burns and heats, the paint on the surrounding casing 28 chars and forms bubbles. This roughened surface reduces the spin rate after motor burnout prior to flare cup ignition. This spin rate reduction occurs from both the increased moment of inertia due to the bubbles as well as increased aerodynamic drag. After flare cup ignition the spin rate is even further reduced due to the heat produced by the burning pyrotechnic. This continues the charring and bubbling action of the paint. Because of this retardation effect on the spin rate, the performance of the flare cup is greatly improved over the normal performance achieved from a rapidly spinning payload.
Having now described the individual components of the personnel distress signal 10, the components accordingly are assembled in the following manner.
First the propellant cartridge 34 is washed and guillotined to length. The necked down delay housing casing 42 is charged with the timing fuse 38 by pressing with the delay composition. Propellant cartridge 34 is inserted into the motor housing casing 28 followed by propellant spacer 32. The propellant ignition charge 36 is then loaded in the propellant passage 73. The nozzle structure 30 and motor assembly 14 are then mated and the motor assembly 14 is pinched or swagged over the nozzle structure 30. The flare pellets 18 are prepared. The kraft paper tube 26 is inserted into the flare cup 16 and the flare pellets 18 are then inserted. The flare ignitor 20 is'then centrally placed into the exposed cavity 27 of the flare pellet 18. The flare pellet 18 and flare pellet ignitor 20 are then compacted or pressed into the flare cup 16. The motor assembly mating surface 45 is then coated with humiseal and the motor 14 and flare assemblies 12 are mated. Humiseal is then applied to the entire flare cup 16 and motor assembly flare cup joint 45. The entire assembly is then painted for environmental protection.
In operation of the personnel distress signal 10 of the present invention, the distress signal 10 is adapted to be fired by, for example, a hand held M207 Launcher or similar equipment having a firing pin operable from triggering means.
With the barrel of the launcher oriented to a suitable angle for accomplishing a desired trajectory, the triggering means of the launcher is displaced which activates the firing pin forward striking the primer 64. Upon explosion of the primer 64, the diaphragm is ruptured and the propellant cartridge 16 ignitor 36 ignites, and consequently the propellant cartridge 34 is ignited.
At the same time the time fuse 38 of the delay train is.
The products of combustion of the propellant cartridge 34 vent through the discharge orifices in the nozzle structure 30, driving the personnel distress signal 10 from the launcher to a predetermined altitude. The plurality of orifices, radially spaced and angularly deposed in the nozzle structure 30, cause the personnel distress signal 10 to spin or rotate about its longitudinal axis imparting gyroscopic stabilization to the distress signal 10 Upon ignition of the timing fuse 38 of the delay train, the material will begin to burn from the rearward end thereof toward the forward end, with such material being transformed into a liquid or semi liquid state due to the heat of combustion thereof. As above described, the radially extending lip 54 prevents the liquid portion of the timing fuse 38 from being forced out of the rearward end of the necked down portion 42 of the motor and delay housing 26 as the distress signal 10 is rotating, thus assuring continuous ignition of the timing fuse 38.
When the personnel distress signal has been propelled to a predetermined altitude, the combustible material of the timing fuse 38 will be completely burned out and will ignite the flare pellet ignitor 20 disposed in the concave recess 27 of the flare pellet l8. Ignition of the flare pellet ignitor results in ignition of the flare pellet 18 which initiates a pyrotechnic display. The pyrotechnic display is adapted to be sustained in the atmosphere until the flare pellet and flare cup are consumed by the combustion thereof.
While it will be apparent that the preferred embodiment of the present invention disclosed herein is well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.
We claim: I
1. In a rocket device,
an elongated generally tubular shaped housing, a cylindrically shaped propulsion charge in one end of said housing,
first means for directing the products of combustion of said charge rearwardly of said housing in a manner so as to impart rotary motion to said device as it is propelled forwardly by said charge,
signal means in said housing,
second means including a combustible material for igniting said signal means at a predetermined time after said propulsion charge has been ignited, and
spacing means located between said first means and said charge for operatively supporting said propulsion charge, said spacing means including an annular shaped transversely extending web section and an axially extending flange located about the outer periphery of said web section and defining symetrical portions on opposite axial ends of said web section, said symetrical portions defining identically formed first and second recess means located on opposite axially spaced ends of said spacing means, one of said recess means cooperatively receiving and radially securing one end of said charge while the opposite symetrical portion selectively locates said charge-in preselected axially spaced relationship relative to said first means.
2. In a personnel distress signal for use in a miniature rocketry system having gyroscopic guiding means, a propulsion charge, a time delay fuse, and signaling means, the improvement comprising means including the blended combination of a pressure insensitive chemical composition and a low gas output chemical composition for igniting said propulsion charge in any natural environment, said pressure insensitive chemical composition comprising granules of boron potassium nitrate and said low gas output chemical composition including finely ground boron barium chromate, whereby at low environmental temperatures, the combustion heat requirement is satisfied by said pressure insensitive composition while at high temperatures, the combustion pressures are not increased by the rate of burn of said pressure insensitive composition.
3. A personnel distress signal for use in any natural environment comprising:
motor housing means defining first and second axially spaced tubular shaped sections,
nozzle means located in one end of one of said first and second sections for imparting a gyroscopic motion to said signal;
motor means located in said one section for providing a source of combustible energy to said signal;
ignition means for igniting said motor means comprising a pressure insensitive chemical composition and a low gas output chemical composition;
signal means connected to said motor housing means for providing a protechnic display, said signal means including a flare cup and a flare pellet located in said cup, said flare pellet including an inward concavely shaped recess, said second section of said housing means extends inwardly in said recess; and
time delay fuse means located in the other of said sections for energizing said signal means after a predetermined time interval commencing after ignition of said motor means.
4. The distress signal as recited in claim 3 wherein one end of said flare cup is formed from a material having a high resistance to oxidation and which is capable of burning with said pellet whereby to contribute to the display.
5. The distress signal as recited in claim 3 wherein one end of said flare cup includes an arcuately shaped iltl wall whereby to promote foliage penetration and to increase the overall flight characteristics.
6. The distress signal as recited in claim 5 wherein said wall approaches the form of an ogive.
7. The distress signal as recited in claim 3 which includes means for inhibiting the rate of combustion of said pellet.
8. The distress signal as recited in claim 7 wherein said inhibiting means includes a paper tube located between an inner peripheral surface of said cup and an outer peripheral surface of said pellet.
9. The distress signal as recited in claim 8 which includes a resin like material coating said tube whereby to prevent an accordian effect when said pellet is disposed in said cup.
10. The distress signal as recited in claim 3 which includes flare ignition means centrally located in said recess forigniting said pellet.
11. The distress signal as recited in claim 3 which includes primer means centrally located in said nozzle means for initiating combustion of said ignitor means.
12. The distress signal as recited in claim 3 which includes rupturable diaphragm means located in an inward side of said nozzle means for hermetically sealing the interior of said housing means and to facilitate a pressure build up therein.
13. The distress signal as recited in claim 12 wherein said motor means is subject to vaporization at high ambient temperatures and which includes sealing means located between said primer means and said nozzle means and between said nozzle means and said housing means for retaining said vapor.
14. The distress signal as recited in claim 3 which includes spacer means located between said nozzle means and said motor means to retain said last mentioned means during combustion thereof.
15. The distress signal as recited in claim 14 wherein said spacer means is comprised of an annular shaped disc having an axially extending flange carried by an outer peripheral surface thereof, said flange extending equally in opposite axial directions relative to the plane of said disc whereby to define first and second recesses on opposite sides of said disc.
16. The distress signal as recited in claim 15 wherein one end of said motor means engages one of said recesses.
17. The distress signal as recited in claim- 15 which includes shoulder defining means formed on an inner surface of one of said sections of said housing means locatably receiving one end and an outer peripheral surface of said flange.
18. The distress signal as recited in claim 3 wherein said motor means includes a centrally located, axially extending passage and wherein said ignition means is disposed in said passage.
19. The personnel distress signal of claim 3 wherein the pressure insensitive chemical composition is Boron Potassium Nitrate.
20. The personnel distress signal of claim 3 wherein the low gas output chemical composition is Boron Barium Chromate.
21. The distress signal as recited in claim 3 wherein said housing means includes orifice means located between said first and second sections and on one side of said fuse means for containment of the reaction products thereof.
24. The distress signal as recited in claim 3 which includes char and bubble forming means responsive to heat generated by said signal means for retarding the rotary motor of said distress signal.
25. The distress signal as recited in claim 24 wherein said last mentioned means includes a paint coating located on the exterior surface of said signal means.