US3121231A - Aircraft tracking colored smoke producing composition - Google Patents

Description

Feb. 11, 964 w. w. REAVES ETAL 3,121,231

AIRCRAFT TRACKING COLORED SMOKE PRODUCING COMPOSITION Filed July 14, 1961 INVENTORJ Kenneth G. Car/on Woodrow "(Reeves BY ,C WM

ATTORNEY N s m United States Patent 3,121,231 AIRCRAFT TRACKING COLORED SMOKE PRODUCING COMPOSITION Woodrow W. Reaves, Baltimore, and Kenneth G. Carlon,

Aberdeen, Md., assignors to the United States of America as represented by the Secretary of the Army Filed July 14, 1961, Ser. No. 124,738 4 Claims. (Cl. 149-84) (Granted under Title 35, US. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment to us of any royalty thereon.

This invention is related to the art of making high speed and high altitude aircraft or missiles visible to the naked eye. of an organic dye with a fuel and an oxidizer from a special container within or attached to the aircraft or missile.

It is Well known in the prior art how to make colored smoke for signal rockets, smoke pots and the like. This is illustratedby the following patents: 2,543,006; 1,319,- 329; 2,419,851 and 1,339,142, and the article in Chemical and Engineering News, vol. 22, #22, November 25, 1944, pages 1990-91, 2056.

In the above prior art, it was common to have an oxi- 3,121,231 Patented Feb. 11, 1964 ice mix is placed in the canisters. In this case, instead of the canister exploding and damaging the aircraft, the nose cone is ejected with little or no damage to the canister or the aircraft.

Referring now to the drawings, FIG. 1 is an isometric view of one embodiment of the invention.

FIG. 2 is a plan view partly in section of the same embodiment.

In the drawing, item 3 represents the electric squib or fuze which is used to set off the mix or composition 17. Immediately below the squib is the exit hole 5 from which the colored smoke issued. The hole 5 is covered by a This is accomplished by burning a mixture dizer and a fuel to vaporize the organic dye. There could also be a cooling agent to lower the temperature of combustion to prevent or decrease the decomposition of the dye. These compositions were designed solely for use at or near sea level.

The present invention is a composition and apparatus for supporting it in use which is designed to be used at an altitude of ,000'-40,000 feet or higher. The existing compositions simply do not function at the low temperatures and low oxygen prevalent at the high altitudes for which the invention is designed.

Thus, theinvention is useful to establish visual contact between jet aircraft prior to a refueling operation. It is further useful as an aerial smoke marker for tracking air movements in the upper atmosphere.

Still further use of the invention lies in its ability to aid in the optical tracking of missiles (air to air and ground to air) since the use of a brilliant color indirect contrast to the blue sky or cloudy sky leaves no doubt as to where the missiles have been or where they are going.

As will be shown later, the compositions set forth in the above prior art were found to be ineffective for use in the high altitudes. Consequently, we had to develop a formulation that would function properly high in the sky. We also had to develop a carrier to hold the composition while it was formed.

It was found during the developmentwork on this invention that the mix or formulation does not always burn uniformly. With certain percentage ranges of the fuel, dye and oxidizer, we found that a surging occurred. In other words, sometimes the outlet of the canister was actually blocked by the molten contents therein. This caused a pressure build up in the canister until the mix was again blown through the outlet. This fact and the ever present chance of human error in compounding the formulation led us to devise the present carrier for air craft shown in the drawings which has a unique safety feature. If the surging persists too long and the pressure becomes too great, the wooden or plastic nose cone of the canister is designed to blow out, thus relieving the pressure. Likewise, the same result obtains if the wrong sealing tape 6 to exclude moisture. The canisters 11 are attached to four cross bars 10 of which only the top two are shown. These bars 10 are in turn attached to a channel iron' 7. On this channel iron are mounted two lugs 8 for attachment of the device to the wings or fuselage of an aircraft Obviously, the device can include a plurality of canisters. The number to be used is a matter of choice depending upon the size and Weight of each canister.

Each of the canisters has a somewhat streamlined nose 9 made of wood or plastic. The one shown is conical or pointed but any other streamlined shape such as bulletnosed maybe used. The nose 9 is held in place by wood screws :12. This is an important facet of the present invention since if the cartridge should explode or exceed a. certain amount of pressure, the screws 12 will pull out or shear off and allowthe nose cone to blow out, thus relieving the pressure and preventing damage to the aircraft wing or fuselage.

The mix or composition 17 is held in a cartridge which is defined by the cylinder 15 and ends 25 and 29. Inside this cartridge is a first retainer ring 20 with an asbestos disc 19. This ring 20 is provided with set screws 18 so that it can be adjustably placed about an inch from the end of the. canister to provide a greater area of combustion during the critical ignition period and to provide for expansion of the composition during its combustion.

This device is essentially a reusable carrier for the cartridges. In order to prevent the heat of combustion from warping or otherwise deteriorating the canisters 11, we

have provided asbestos insulating means such as the washers 26 and 27 and canister liner 13.

On the end of canister 11 we provide a second retaining ring 21 with set screws 22 which keeps the cartridge 1 in place. After the cartridge has been fired from electric controls in the airplane, the cartridge can be replaced by a new one by merely unscrewing the set screws 2/2 back into the canister 1'1 and pulling out the retaining ring 21 and the cartridge.

The firing mix or composition was developed by us as a result of a series of test firings as set forth in the following tables:

TABLE II Flight Tests of the Formulation of Table I Test gisgg fg Burning time Remarks Alti Air Temp. Test tude,it. Speed, F. Remarks Red g; No time Ignition very slow b0- knots 18 cause of lag.

2 1 7, 000 140 70 Units burned for approximatcly a $52,31 3, 1 39sec" Igmtwnlaa min. Good volume of smoke. NEHCOSZ: 14 2 91500 140 8 Umts burned 3 mq 15 Red dye--. 57 lgnition,smoke color and Volume of smolta l l dlve K0103..-" 25 2min volume were satisfacthere was a. slight dissipation of 18 t0ry a smoke. H v 16 Red dye... 57 3 110,000 135 -35 20 see. after ignition theunitsemitted K0103 25 2mm n Same as test #12 a very faint trace of smoke not Thiomfea 18 visible to the naked eye but discernible through a 10 power telescope. After 45 see. the burning rate increased and a faint trace oi TABLE V smoke was visiblle to the naked eye or approximate y 5 min. 4 30,000 135 35 Units were ignited under the some Fllght Tests of Composmons condlitions as test #3hwigh the same ifif s figaggg ,f gfiglifi; Test Formulation (parts Burning time Remarks the smoke visible to the naked eye. 20 by weight) 1a gym... 60 {Altitukde $0,000 int. speeg 2O 1 min 150 no s, igni ion an TABLE III Thiourea smoke satisfactory.

game min, 40 sec.. game. i 1 1 ame.. IHlll 3.1110. Comparison of me Burning Times 0 Units Reddye Air temperature atSea Level and 30,000 Feet K010 3min altitude 30,000, speed Thiourea... 18 247 knots. Good, visiole smoke trail. Composition Altitude Burning time Remarks m" 55 Same- 2rn1n.,15 scc-. Same. 3 min., 10 sec.. AltizisiglFe 30,000d temp. The units were brou h to SD60 570 Red d c 40 5 F and g gn knots, smoke trail cx- Koloy fired. The ignition sys- T e scalcvel. 1min tern ngstnliodqi ficd inka. Same Mtlmetakenggg g I ;l

j minor cai. iesmo e I was considered satisfaeknots, 51110116 trail 0X- tory. cellcnt.

Same 30,000...- 5min.,30scc. S icedl 140 knots. stmoke 6m r Y O m as am 35 NOTE 1.-In all the above tables the composition was pressed into the canisters under 20 tons pressure.

NOTE 2.-The red dye used was l-methylaminoantliraquinonc. NOTE 3.'1l1e formulations are given in parts by weight not in percent- TABLE IV age by weight for convenience in compounding.

- We have illustrated our invention with only one heat Tests Conducted to S eed u Burnm Tzme at Sea Level p p g 40 stable dye. It is obvious that other brightly colored dyes w 1 A, could be used in place of the red dye used above. Thus,

Test g; jg g Bummg Remarks the yellow, orange or violet dyes set forth in the aforementioned Chemical and Engineering News article can TOO much Surging m be substituted in the above formulations. The only 1 llecdlgye.-- 42 th loutlletkvvlas iter- 45 requirements for the dye to be used 18 that they contrast i- 1111111.,25 sec.- gfl g $1 33 sharply with the natural blue sky and that they are Nal'IOO..- 10.0 that torns on these relatively heat stable.

2 Red 53, 5 in general the composition we have developed for high gg l gifl 1mm" 15 sec" Same asabom altitude tracking has in it arange of fuel from 15-25 Mgiooitf. 3.5 parts by weight with the oxid zer being presentnn ap- 3 83 S3 52 Se q m S b 0 proximately equal amounts. The heat stable dye is presfjjj: 12:00 O a a ent in the mixture in an amount such that the approxisec i sg g eg fi mate total Weight of the dye, oxidizer and fuel is about x0 Thiouiw" 2M0 1 smokewm good 0 100 un ts. We have found that a mixture of 57 parts 5 6 83 32 Sec 55 by weight 1-methylaminoaiithraquinone, 25 parts by iggj: 24 weight potassium chlorate and 18 parts by weight of thio- 6 6 8?"- g urea gives the best results for this work. This has met 51: i Imlmslble to lgmlethe requirements of the US. Navy for such a composition.

7 ggg We have found further that another fuel, tctrarnethyl j: 23 5 Sec 60 thiuram disulfide may be used for the thiourea used above with approximately the same results. 52 We claim: ggggg g8 1min ,12 sec" Ignition lag at 1 1. A composition for the production of colored smoke, Urea 6 comprising a mixture of a heat-stable organic dycstuii,

9 gag g8 an oxidizing agent and a fuel which is a member of the T I {%,g g 11n1n.,25sec-- Same as above. group consisting of thiourea and tetrarnethyl thiuram 1C Red dye 42 Ignition was Slow. SW disulfioe, said fuel and said oxidizing agent being present KC1O3 22. 1mm 20 Sec i l starters did not in amounts sufiicient to ignite and burn whereby said 'lghifiigga... implgoIvc ignition at d t fl i vaporized 11 Red dye-.. 5o Smokcvolumcand buli'lv 2. A composition for the production of colored smoke gfitgi 38 11111- 5 3 sanscomprising a mixture of a heat-stable organic dyestuif, R dd 6 on u its i vere given rough potassium chlorate and thiourea, said potassium chlorate 12 0 ye... 0. .an in, vibration a Koloaflm 20-00 min, 10560 and 40 aft. drop tests and said thiourea being prcsent in amounts sufiicient to Tii r mm and were found sgtisignite and burn whereby said oyestuif is vaporized.

factory.

3. A composition for the production of colored smoke comprising a mixture of 1-methylaminoanthraquinone, potassium chlorate, and thiourea, said potassium chlorate and said thiourea being present in amounts suflicient to ignite and burn whereby said l-methylamino anthraquinone is vaporized.

4. A colored smoke producing composition comprising the following ingredients in parts by Weight:

References Cited in the file of this patent UNITED STATES PATENTS Orelup Apr. 29, 1947 Finkelstein et al. Feb. 27, 1951 Clay et a1. Nov. 10, 1953 Woyski et al. Jan. 31, 1956 Johnson et a1 Jan. 13, 1959 Tabor et al. Jan. 10, 1961 Butler Sept. 4-, 1962

Claims (1)

1. A COMPRISING FOR THE PRODUCTION OF COLORED SMOKE, COMPRISING A MIXTURE OF A HEAT-STABLE ORGANIC DYSTUFF, AN OXIDIZING AGENT AND A FUEL WHICH IS A MEMBER OF THE GROUP CONSISTING OF THIOUREA AND TETRAMETHYL THIURAM DISULFIDE, SAID FUEL AND SAID OXIDIZING AGENT BEING PRESENT

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