US2892305A - Rocket propulsion method - Google Patents

Description

June ,1 A. ZLETZ ETAL 2,892,305

' ROCKET PROPULSION METHOD Filed Feb. 16, 1953 OXIDIZER Alex Z/efz Don R. Carmady INVENTORS:

ROCKET PROPULSION METHOD Alex'Zletz, Park Forest, and Don R. Carmody, Crete, 11L, assignors to Standard Oil Company, Chicago, 111., a corporation of Indiana Application February 16, 1953, Serial No. 336,902

14- Claims. (Cl. 6035.4)

This invention relates to the generation of gas. More particularly, it relates to reaction propulsion by the hypergolic reaction of a liquid fuel and a liquid oxidizer. Still more particularly, the invention relates to a method of rocket propulsion by the hypergolic reaction of a fuel and a hydrogen peroxide oxidizer, which materials spontaneously react to generate gas at high pressure and high temperature.

Reacton propulsion is now being used for many aerial purposes. For many uses it is necessary to operate with a fuel system which is not dependent on atmospheric oxygen. This fuel system may consist of a single self-contained propellant or it may consist of a separate fuel and a separate oxidizer, i.e., a bipropellant system.

In the bipropellant system the fuel and the oxidizer are introduced separately and essentially simultaneously into the combustion chamber of the reaction motor. The products of oxidation from the reaction of the fuel and the oxidizer are discharged through an orifice at the exit end of the combustion chamber and thereby produce the driving force. Because'of the possibilities of electrical and/or mechanical failure of the auxiliary methods of ignition such as a spark or a 'hot surface, it is preferred to use a self-igniting fuel system. A fuel which is self-igniting, i.e., spontaneously combustible when contacted with an oxidizer, is known as a hypergolic fuel.

Temperature has an important elfect on the hypergolic activity of fuels. The temperature at the earths surface may vary from a high of about +125 F. to a low of as much as 65 F.; in general temperatures below about -20 or 30 F. are exceptional. Thus surface-to-air missiles or rocket-driven aircraft should be capable of operation when the temperature of the fuel and the oxidizer at the moment of initial contact in the combustion chamber of the rocket motor is on the order of -20 F. Temperatures at high altitudes are frequently on the order of -65 F. and are known to ap proach 100" F. Thus an air-to-air missile should be able to operate satisfactorily when the temperature of the fuel and the oxidizer at the moment of initial contacting in the combustion chamber is on the order of The more common oxidizers are white fuming nitric acid, red fuming nitric acid and nitric acid-sulfuric acid mixtures. While these nitric acid oxidizers operate satisfactorily over a wide range of atmospheric temperatures they have important drawbacks. The nitric acid oxidizers are extremely corrosive; they have poor storage stability; they give off toxic gases; and special precautions must be taken by personnel who handle these oxidizers.

Concentrated aqueous hydrogen peroxide solutions have excellent storage stability and do not give off harmful gas. However, these aqueous hydrogen peroxide solutions such as 90% hydrogen peroxide have the disadvantage of comparatively high freezing points, e.g., 90%

aqueous hydrogen peroxide solutions containing at least i Patented June 30, 1959 hydrogen peroxide solution freezes at +12 F. The freezing point of hydrogen peroxide is --9 F., but the activity of this solution toward the prior art fuels is markedly lower than the H 0 solution. The freezing point of aqueous hydrogen peroxide solutions can be depressed by dissolving therein inorganic salts, preferably ammonium nitrate. Thus a solution containing 40 weight percent of ammonium nitrate and in which the hydrogen peroxide-water portion contains 90 weight percent of H 0 has a freezing point of about 30 F. A so-called 80% H O -30% NH NO solution has a freezing point of below 70 F.

Concentrated aqueous hydrogen peroxide solutions have been used as monopropellants by catalytically decomposing the hydrogen peroxide, using such catalysts as potassium permanganate or copper oxide. Since the decomposition products contain free-oxygen the monopropellant system is ineflicient. However, fuels which are hypergolic with nitric acid oxidizers may be much less active or even inactive with concentrated H 0 solutions. Anhydrous hydrazine is usually considered to be the only fuel that is sufificiently hypergolic with concentrated H 0 solutions to be practical; however, hydrazine has the disability of a comparatively high freezing point. Some fuels are operative with H 0 solutions in the presence of a H 0 decomposition catalyst.

An object of this invention is a method of generating gas by the hypergolic reaction of a fuel and a hydrogen peroxide oxidizer. Another object is a method of reaction propulsion by the hypergolic interaction of a fuel and a hydrogen peroxide oxidizer. Still another object is a method of reaction propulsion by the hypergolic interaction of a hydrogen peroxide oxidizer and a fuel which contains appreciable amounts of miscible hydrocarbons, particularly non-hypergolic liquid hydrocarbons. propulsion by the hypergolic interaction of a defined organic phosphine and a defined hydrogen peroxide oxidizer when the temperature of the fuel and the oxidizer is above about 20 F. Other objects will become apparent in the course of the detailed description of the invention.

A method has been discovered for generating gas,

which gas may be used as a substitute for compressed air for certain purposes or for driving the turbine of a jet engine or for rocket propulsion, which method comprises contacting 1) A fuel consisting essentially of at least one member selected from the class consisting of (A) Monoaliphatic phosphines which contain not 7 more than 16 carbon atoms,

(B) Dialiphatic phosphines which contain not more than 20 carbon atoms and wherein each aliphatic radical contains not more than 12 carbon atoms, and

(C) Trialiphatic phosphines which contain not more than 24 carbon atoms and wherein each aliphatic Mono-octyl phosphines containing as much as 6 0 volume percent of miscible hydrocarbon are hypergolic with Another particular object is a method of rocket with thesameoxidizer. However, by proper selectionrof the phosphine, it is possible toobtainza hypergolic reac.-- tion with a tolerable ignition delay when thephosphine and the oxidizer are at a temperature of about- F.

at the moment of initial contact in the gas generating.

chamber.

Certain monoaliphatic phosphines, dialiphatic phosphines,. trialiphatic phosphines and mixtures thereofare useful for the purposes of this invention. These'aliphatic phosphines have the generic empirical formula RRR"P where}? represents the element phosphorus, R represents an aliphatic radical and R and R represent the same or different radicals selected from the class consistingof aliphatic and hydrogen. The term aliphatic as, used herein is intended to include hydrocarbon radicals selected from the class consisting of parafiins, olefins and naphthenes. In the case of naphthenic radicals, the

radical may be attached to the phosphorus either through.

a ring carbon atom or through aside chain carbon'atom. It has been found that the highly branched aliphatic-substituents have desirably lower freezing points than the straight chain or slightly branched substituents. It is preferred to use branched aliphatic substituents. The presence of unsaturated linkages in the aliphatic substituent improves the hypergolic activity. A particularlyuseful aliphatic phosphine contains not only a highlybranched aliphatic radical, but also containsone or more unsaturated linkages.

Ithas been found that the hypergolic activity of the various aliphatic phosphines is dependent upon the number ofaliphatic radicals, upon the total number of carbon atoms contained in the phosphine, and upon the number of. carbon atoms contained in each of the aliphatic radicals. In order to obtain a fuel which is usable at low temperatures, it is necessary that the monoaliphatic phosphines contain not more than 16 carbon atoms. The phosphines which contain two aliphatic radicals, i.e., dialiphatic phosphines, must contain not more than 20 carbon. atoms in the molecule and furthermore, each aliphatic radical must not contain more than 12 carbon atoms. Thus a dialiphatic phosphine which contains a 12 carbon atom. side chain must not contain more than 8 carbon atoms in. the second side chain. The completely substituted phosphines, i.e., trialiphatic phosphines, must not contain more than 24 carbon atoms in the molecule and furthermore, no aliphatic radical must contain more than 12 carbon atoms. Thus a trialiphatic phosphine which contains a 12 carbon atom side chain will contain only, for example, two hexyl or one octyl and onejbutyl radical' as the other radicals.

When it is desired to initiate thecombustion at low temperatures on the order of 20 F., itis preferred to use the following fuels: monoalkyl phosphines which contain-not more than 8 carbon atoms; dialkyl-phosphines which contain not more than 12 carbon atoms and wherein each alkyl radical contains not more than 8 carbon atoms; trialkyl phosphines containing not more than 12 carbon atoms total and not more than 8 carbon atoms in any alkyl radical. The. preferred species for operation at-gstartingtemperatures of about -20P F. are the tributyl phosphines and mono-n-octyl phosphine.

A=.mixed fuelwhich is suitable for the generationof: gas fon-reaction. propulsion when the fuel andthe-oxidi'zer are at-ya temperature of at. least about +60 F. can; be made by mixing an alkyl phosphine which contains :not: more than 12carbon atoms with a miscible hydrocarbon. An elfective amountof phosphine must necessarily be present inthe mixed fuel in order to obtain the hypergolic. reaction. amount will vary with both the type of hydrocarbon The' andv the species of phosphine. When usingamono-octyL phosphine and aromatic hydrocarbon mixture, as much as 60 volume percent of the mixed fuel may be aromatic hydrocarbons. In general petroleum hydrocarbon fractions are suitable materials, for example, those fractions boiling between about 300 and 600 P. which correspond to the fuel requirement of military jet engines. Aromatic hydrocarbons which boilbelow about 600 F. are suitable hydrocarbons for this purpose. The. hypergolic activity of the mixed fuel can be improved. at temperatures below about +60F. byusing asthehydr'ocarbon component olefinic hydrocarbons such as thermally'crackednaphthas'and-gasoils or turpentine. Conversely, at temperatures above about 60 F., a hypergolic mixed fuel containing less than about 40 volume percent of mono-octyl phosphine is obtainable by the use of olefinic hydrocarbons.

The OXldlZfil'SfOfillhiS? invention are either concentrated aqueous hydrogen peroxide solutions or aqueous hydrogen peroxide solutions containing dissolved inorganic: salts, for example, ammonium halides, sodium sulfate, sodium;.nitrate, etc;;,the inorganic nitrates are preferred. The concentrated. aqueoushydrogen. peroxide solutions: should contain at least; about; Weight percent: of H 0 the remainder of the solution is essentially water.

The hypergolic activityof theaqueous hydrogen peroxide solution is' improved by increasing. theiconcentration-z of the peroxide. Commercially available 9.0% H 0 solution is apreferredoxidizer. Still more concentrated: solutions are; better when. operation. abovetthe; freezing: point of the-solutions is. desired.

Concentrated. aqueous hydrogen peroxide solutiorras made commercially: is; virtually only H 0 and: water; In. order-to improve storage stabilitysmall. amounts of'stabi'-. lizers may be added'to thGISOllltlOl];6:g.,.SOClll.1HI stannate;

tetrasodium pyrophosphate, adipic acid, tartaricwacid; iin':

general only trace amounts of stabilizersare added so;that-'; the solution consists essentially of-hydrogen peroxide: and water.

lnzordertor depress thefreezing'point' ofaqueous'hydrogenperoxide solutions soluble inorganic saltsv are dis solvedtherein, e.g., sodium. nitrate, ammonium chloride.

and ammonium nitrate have beenused. The preferred: These salt-containing SOllll-g salt is ammonium nitrate. tions; are commonly designated, in terms of the; weight percent of salt inthe total solution and the weightpercent:

of hydrogen peroxide present in the aqueousportion of;

the solution, e.g., -H O 40% NH NO ,indicatesthat'the total aqueous hydrogen peroxide-nitrate-solutiom consists of 40 weight percent of ammonium nitratezand- 60 weight-percent of aqueous hydrogen peroxide com-; posed of 90 weight percent of. H O -and the remainderessentially water. This particular solution has a freezing point of about 30 F. A temperature of -70 F. is. attainable with an 80% H O 30.% NH NO solution..-

It is preferred to operate in the absence of-soluble inorganic .saltsbecause thesessalts have-an adverse effect on.

the hypergolic activity of the fuels of this invention.

The aliphatic. phosphines are in'general clear, mobile,

high-boiling liquids with an unpleasant odor. They are.

fairly stable when exposed. to elevated temperatures in the absence of air, but are extremely susceptible'to-oxidar,

which involves the reaction of phosphine. and an olefin.

The product'sfrom allof these methods ofpreparation 7 contain minor amounts of impurities. These impurities have a favorable effect on the freezing point of the aliphatic phosphines and appear to have no substantial adverse effect on hypergolic activity. It has also been found that the aliphatic phosphines which have been oxidi zed to a minor extent, e.g., 4 or 5%, are useful as hypergolic fuels. It is intended to include within the scope of the invention the use of aliphatic phosphines which contain minor amounts of impurities resulting from the preparation thereof-and also those which contain minor amounts of oxidation products resulting from the oxidation of the aliphatic phosphine.

The aliphatic phosphines are particularly suitable fuels for rocket propulsion because of their low freezing points,

high, boiling points, and small increase in viscosity with decrease in temperature. In addition to their low freezing points they also have a considerable tendency to supercool, i.e., remain liquid at temperatures below the truegfreezing point. Most of these compounds do not form a crystalline mass when solid, but solidify inthe form of a glass. 4

.Several aliphatic phosphines were prepared by the methods of the literature. The method of. Davies and Jones supra was used to prepare a high purity tri-n-buty1 phosphinej The method of Davies supra was used to prepare a highpurity tri-secondary butyl phosphine, and also trimethyl phosphine. The method ofU.S. Patent 2,584,112 was used to react n-octene, 2-ethy1-1-hexene and a propylene tetramer with phosphine. In each case a mixture of substituted phosphines resulted and this mixture was carefully fractionated to produce cuts which were predominantly mono, di and tri-alkyl phosphines. The physical characteristics of some of the materials which were used in the tests to be described later are listed below:

Specific B.P. Phosphine Gravit F.P., F

F. mIn.Hg

1 Propylene tetramer.

3 Very viscous fluid.

The ignition characteristics of various fuels were studied using a drop test. This method utilizes a test tube, 1 in. x 4 in., containing about 0.5 m1. of oxidizer. The fuel to be tested was drawn into a hypodermic syringe. It was then ejected forceably against the oxidizer surface by depressing the syringe plunger. By this method amounts of fuel of as little as 0.01 ml. can be added. Low temperature tests were carried out by cooling the test tube and the oxidizer contained therein by means of a bath; a drying tube inserted into the top of the test tube excluded moisture. The fuel was cooled separately to the desired test temperature. By supercooling it was possible to carry out tests at temperatures below the freezing point of the fuel and/ or the oxidizer.

The ignition delay, which is the time elapsing between the addition of fuel to the oxidizer and visual ignition thereof, was determined visually as either (a) very short which corresponds to substantially instantaneous ignition, (b) short, which corresponds to substantially.

less than 1 second, and (c) more than 1 second, which time was determined by a stop watch.

The following tests illustrate the activity of some of the alkyl phosphines of this invention and hydrazine with hydrogen peroxide oxidizers.

TestI Various phosphines were tested for hypergolic activity at a temperature of about +70 F. using 0,5 ml. of 90% H O as the oxidizer.

I Considerable etfervescence. h Prepared from l-octene. Prepared from 2-ethylhexene. 15 Prepared from propylene tetramer.

Test II In this test several runs were made contacting various phosphines at about +70 F. using 80% H 0 solution as the oxidizer.

Fuel Ignition Run No. Fuel Atlilled, Delay 10 Monom ctyl) 0.06 No ignition (efiervescence) ll dn 0. 08 Short.

Mono (2-ethylhexyl) 0. 06 Do. Tri(n-butyl) 0. 06 Do.

Test lll In this test several runs were made using various phosphmes at different temperatures with either 90% H 0 or 80% H 0 solutions as the oxidizer.

' 2 Run Fuel Fuel Oxi- Temp., Ignition 40 No. Added, dizer, F. Delay ml. percent 14.-- Mono(n-octyl) 0.08 90 0 2sec. 15 0 0.12 90 20 Short. 16....-- Mono(2-ethylhexyl) 0.06 90 0 fisec. 17 do 0. 14 90 20 4 sec. 18. Tri(n-butyl) 0.08 90 0 Very short 19- o 0.12 90 20 Short. 20. Tri(sec-butyl) 0.10 90 0 Do. 21. 0 0.14 90 20 Do. 22;--- M0no(n-octyl) 0.08 80 +14 Do.

o 0.08 80 20 2 sec.

Mono (2-ethy1hexyl) 0. 06 80 +14 Do.

' 0. 08 80 22 15 sec.

0. 12 80 +14 N o ignition (effervescence).

Test IV For comparative purposes hydrazine was contacted at various temperatures with either 90% H 0 or H 0 solutions as theoxidizer.

In order to observe the efiectiveness of phosphines with oxidizers consisting of aqueous hydrogen peroxide-am monium nitrate solutions, a run was made using 0.5 ml. of a %-40% aqueous hydrogen peroxide-ammonium 7 nitrate solutions as the oxidizer.

Rum Fuel Qxidlzer Igni- No. Fuel Added, H O NH4NO Temp, tlon ml. percent F. Delay,

sec.

30. Mono 0. 02. 9040 +70 2 (nroctyl).

Runs 2. and 30 show the adverse effect of dissolved ammonium nitrate on the. ignition delay.

Test VI' The hypergolic activity of mixtures of phosphine and benzene was tested at about, +70" using 0.5 ml. of

It is obvious from the data presented above that this invention can be used to generate gas at high pressure. Thisa gas. can be used for operating machinery. such; as

compressed air hammers or for aircraft catapults; an-

other important use. for this high pressure gas; is in; the starting of the turbines of jet-type engines. The invention isparticularly useful for operations which require a compact power plant that is able to produce a large amount of energy over a very short period of time. Other examples of uses. of this: invention are: the rocketassisted take-off or flight of aircraft; aerial missiles;

boostersfor surface vehicles.

The relative proportion of oxidizer-toefuel usedwill depend upon the type of operation, the. temperature. of operation and the type. of fuel and oxidizer-being used. When using 90% H solution as.the. oxidizer andtrilbutyl phosphine as the. fuel, between about 4.5-and 55 volumes of oxidizer are needed per volume of fuel.

By way of example. this invention is applied to-the propulsion of a ground-to-air missile. The. annexed figure which forms a part of this specification shows schematically the bipropellant feed system and the motor of this missile. This same type of missile could be used as a ship-to-air missile. This missile is suitable for operations wherein the fuel and the oxidizer can be maintained at a.temperature-high enoughto insure-at least a short ignition delay, e.g., when .using 90% H O zas. the. oxidizer and tributyl phosphine as thefuel,.a -temperatnre of about F.

In the drawing vessel 11 contains a quantity of gas at high pressure; this gas must be inert with respect to the oxidizer and the fuel; suitable gases are nitrogen and helium. Hereinhelium is used as theinert gas. Helium from vessel 11' is passed through line 12 and throug valve 13 which regulates the flow of gas to maintain a constant pressure beyond valve 13. helium is passed through lines 14 and 16. into vessel 17 and simultaneously through line 18 into vessel 19.

Vessel 17 contains the oxidizer. Helium pressure forces theoxidizer out of vessel 17 through line 21 to valve 22. Valve 22 is a solenoid actuated throttling valve. Suitable electrical lines connect'valve 22"t0 an electrical source and operating switch (not shown) at the control chamberat the'launching site. The oxidizer is passed through llne 23 and llljCCiOlZd ll'lto'gombusfign h b r From valve: 13

. 8 l 26. Combustion chamber 26 is provided with an outlet nozzle 27."

Vessel19 contains the fuel. Vessels '17 and 19 areconstructed" to withstand the high pressure imposed by the; helium gas. The gas pressure forces fuel from vessel 19" through line 28. to solenoid actuatedthrottling-valve 29. Valve 29 is similar in construction and in actuation" to valve 22:. The fuel is passed through line 31 and-injector 32.. into combustion chamber-26.,

Valves 22 and 29 are of sucha size and'setting that a predetermined ratio of oxidizer-to-fuel is passed into combustion chamber 26. Injectors 24 and- 32* are so arranged that the streamsof oxidizer and fuel converge and contact each other forcibly, resulting in; a very} thorough intermingling of the fuel and the oxidizer;

The missile is launched by activating the solenoids on valves 22' and 29; In this example 5.2 volumes of 90% H20 solution per volume of phosphine is introduced into the combustion chamber. The oxidizer and the fuel react almost instantaneously upon contact" in the com bustion chamber; a large volume of very hotgasis produced; in the combustion chamber, which gas escapes through orifice 27. The reaction from this expulsion of gas drives-the missile toward its target.

Thus-having, described the invention, what is claimed is;

1-. A method of generating gas, which method comprises injecting separately and essentially simultaneously into the combustion chamber of a gas generator (1;) a

30 hypergolic fuel consisting essentially of-a member selected" from the class consisting of (i) monoalkyl' phosphi-nes containing not more than 8 carbon atoms, ii) dial-kyl" phosphines containing not more than 12 carbon atomsand each'alkyl radical contains not morethan 8' carbon; atoms and (iii) trialkyl phosphines containing not morethan- 1-2 carbon atoms and not more than- 8 carbon atoms in an organic group, and (2') an oxidizer selected from the class consisting of (a) aqueous hydrogen peroxide solutions consisting of at least about weight percent of H 0 and the remainder essentially water and (b)- aqueous. hydrogen peroxide-ammonium nitrate. solutions wherein the. hydrogen peroxide-water portion isthe pref dominant component and consists of at least abouts!) weight percent of H 0 and the remainder essentially water, in an amount and at a rate sutficient to initiate 3. The method of claim 1 wherein said fuel is .diqctylf phosphijne.

.4. The method of claim 1 wherein said fuel is monod'odecylphosphine.

5.'The method of claim 1 wherein said 'fuel is monooctylphosphine.

6. The method of claim 1 wherein said oxidizer cor1- sists of about 8.0 weight percent of H20 and the remainder essentially water. 7

7'. The method of claim 1 wherein said oxidizer con,- sists ofabout weight percent of H 0 and the remainder essentially water.

8; The method of claim 1 wherein said oxidizer consists of; a solution of hydrogen peroxide, water and ammonium nitrate, wherein the nitrate content is about 3Q weight percent and, the hydrogen peroxide-water portion consists of about 80 weight percent of'H O and the remainder essentially water.

9. The methodv of claim 1 wherein said oxidizer consists of a solution of hydrogenperoxide, water andammonium nitrate, wherein the nitrate content is about 40 weight percent and the hydrogen peroxide-water port-ion consists of about 90 weight percent of H 0 and the remainder essentially water.

10. A method of generating gas, which method comprises injecting separately and essentially simultaneously into the combustion chamber of a gas generator (1) a hypergolic mixed fuel consisting essentially of (I) a liquid miscible hydrocarbon and (II) monooctyl phosphine and (2) an oxidizer selected from the class consisting of (a) aqueous hydrogen peroxide solutions consisting of at least about 80 weight percent of H 0 and the remainder essentially water, and (b) aqueous hydrogen peroxide-ammonium nitrate solutions wherein the hydrogen peroxide-water portion is the predominant component and consists of at least about 80 weight percent of H 0 and the remainder essentially water, in an amount and at a rate suflicient to initiate a hypergolic reaction with and to support combustion of the mixed fuel.

11. The method of claim 10 wherein said hydrocarbon is a liquid petroleum traction boiling between about 300 and about 600 F.

12. The method of claim 10 wherein said hydrocarbon is a liquid aromatic hydrocarbon boiling below abou 600 F. t

13. The method of claim 10 wherein said hydrocarbon is a liquid olefin boiling below about 600 F.

14. The method of claim 12 wherein said hydrocarbon is benzene.

References Cited in the file of this patent UNITED STATES PATENTS 53,695 Somes Apr. 3, 1866 10 2,368,866 Nygaard et a1. Feb. 6, 1945 2,573,471 Malina et a1 Oct. 30, 1951 2,584,112 Brown Feb. 5, 1952 OTHER REFERENCES Hackhs Chem. Dictionary, 3rd ed. (1 944), pp. 30, 559. Jour. of Amer. Rocket Soc., No. 72, December 1947, pp. 17, 21, 26, 31-38. Y

Claims (1)

1. A METHOD OF GENERATING GAS, WHICH METHOD COMPRISES INJECTING SEPARATELY AND ESSENTIALLY SIMULTANEOUSLY INTO THE COMBUSTION CHAMBER OF A GAS GENERATOR (1) A HYPERGOLIC FUEL CONSISTING ESSENTIALLY OF A MEMBER SELECTED FROM THE CLASS CONSISTING (I) MONOALKYL PHOSPHINES CONTAINING NOT MORE 8 CARBON ATOMS, (II) DIALKYL PHOSPHINES CONTAINING NOT MORE THAN 12 CARBON ATOMS AND EACH ALKYL RADICAL CONTAINS NOT MORE THAN 8 CARBON ATOMS ATOMS AND (III) TRIALKYL PHOSPHINES CONTAINING NOT MORE THAN 12 CARBON ATOMS AND NOT MORE THAN 8 CARBON ATOMS IN AN ORGANIC GROUP, AND (2) AN OXIDIZER SELECTED FROM THE CLASS CONSISTING OF (A) AQUEOUS HYDROGEN PEROXIDE SOLUTIONS CONSISTING OF AT LEAST ABOUT 80 WEIGHT PERCENT OF H2O2 AND THE REMAINDER ESSENTIALLY WATER AND (B) AQUEOUS HYDROGEN PEROXIDE-AMMONIUM MITRATE SOLUTIONS WHEREIN THE HYDROGEN PEROXIDE-WATER PORTION IS THE PREDOMINANT COMPONENT AND CONSISTS OF AT LEAST ABOUT 80 WEIGHT PERCENT OF H2O2 AND THE REMAINDER ESSENTIALLY WATER, IN AN AMOUNT AND AT A RATE SUFFICIENT TO INITIATE A HYPERGOLIC REACTION WITH AND TO SUPPORT COMBUSTION OF THE FUEL.

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