web.archive.org

N2O4/UDMH

www.spacedaily.com
SPACE.WIRE

8K84 back
Credit: © Mark Wade

Propellant: N2O4/UDMH. Oxidiser: N2O4. Fuel: UDMH.
Propellant Formulation: N2O4/UDMH. Optimum Oxidiser to Fuel Ratio: 2.61. Temperature of Combustion: 3,415.00 deg K. Ratio of Specific Heats: 1.25. Density: 1.18 g/cc. Characteristic velocity c: 1,720 m/s. Isp Shifting: 285. Isp Frozen: 273. Pp Isp Shifting: 336. Isp: 285.00 sl. Isp: 333.00 vac.

Oxidiser: N2O4. Oxidiser Density: 1.45 g/cc. Oxidiser Freezing Point: -11.00 deg C. Oxidiser Boiling Point: 21.00 deg C.
Nitrogen tetroxide became the storable liquid propellant of choice from the late 1950's. Nitrogen tetroxide consists principally of the tetroxide in equilibrium with a small amount of nitrogen dioxide (NO2). The purified grade contains less than 0.1 per cent water. Nitrogen tetroxide (N2O4) has a characteristic reddish-brown colour in both liquid and gaseous phases. The solid tetroxide is colorless. N2O4 has an irritating, unpleasant acid-like odour. N2O4 is a very reactive, toxic oxidiser. It is non-flammable with air; however, it will inflame combustible materials. It is not sensitive to mechanical shock, heat, or detonation. Nitrogen dioxide is made by the catalytic oxidation of ammonia; steam is used as a diluent to reduce the combustion temperature. Most of the water is condensed out, and the gases are further cooled; the nitric oxide is oxidised to nitrogen dioxide, and the remainder of the water is removed as nitric acid. The gas is essentially pure nitrogen tetroxide, which is condensed in a brine-cooled liquefier. 1959 production amounted to 60,000 tonnes per year. In carload lots of one-ton cylinders, the price was $ 0.15 per kg. By 1990 NASA was paying $ 6.00 per kg due to environmental regulations.
Fuel: UDMH. Fuel Density: 0.79 g/cc. Fuel Freezing Point: -57.00 deg C. Fuel Boiling Point: 63.00 deg C.
Unsymmetrical Dimethylhydrazine ((CH3)2NNH2) became the storable liquid fuel of choice by the mid-1950's. Development of UDMH in the Soviet Union began in 1949. It is used in virtually all storable liquid rocket engines except for some orbital manoeuvring engines in the United States, where MMH has been preferred due to a slightly higher density and performance. Unsymmetrical dimethylhydrazine (UDMH) is 98 to 99 per cent pure and is described by Military Specification MIL-D-25604. The normally expected impurities are dimethylamine and water. UDMH is a clear, hygroscopic liquid which yellows on exposure to air. It absorbs oxygen and carbon dioxide. UDMH is a toxic volatile liquid. It exhibits the sharp ammoniacal or fishy odour which is characteristic of organic amines. It is completely miscible with water, ethanol, and most petroleum fuels. It is not shock sensitive. The vapours are flammable in air over 2.5 to 95 per cent concentration range. UDMH can be produced commercially by nitrosation of dimethylamine, to N-nitro-sodimethylrtmine, followed by reduction of the intermediate to UDMH and subsequent purification. UDMH can be prepared, also, by a modification of the Raschig process (see discussion of hydrazine), in which the chloramine intermediate is with dimethylamine rather than with ammonia. The price in 1959 for tank-car quantities was under $ 1.00 per kg. Engineering studies indicated a price of $ 1.00 per kg with large scale sustained production. But due to its toxic nature, production and transport costs soared in response to environmental regulations. By the 1980's NASA was paying $ 24.00 per kg.
Engines Using N2O4/UDMH

Engine Thrust(vac)
kgf Thrust(vac)
kN Isp
sec Isp (sea level)
sec Designed for Status
RDMT-0.4 X 0.0410 0.00040000 290 Upper Stages In Production

11D431 0.6 0.005880 Upper Stages In Production

RDMT-8 X 0.8 0.00800 296 Upper Stages Developed 1980's

Stepanov IS/US 1 kgf 1 0.00980 Upper Stages Out of Production

RDMT-12 1 0.01200 279 Upper Stages In Production

17D58E 1 0.01330 247 Upper Stages In Production

DST-25 3 0.0250 285 Upper Stages In Production

RDMT-50 5 0.050 255 Upper Stages In Production

11D446 5 0.052 Upper Stages In Production

11D445 7 0.065 Upper Stages In Production

Stepanov LK/LOK 10 kgf 10 0.098 Upper Stages Out of Production

DST-100A 10 0.100 304 Upper Stages In Production

RDMT-100 10 0.100 260 Upper Stages In Production

DST-100 10 0.100 276 Upper Stages In Production

11D428 11 0.110 Upper Stages In Production

RDMT-135 14 0.135 260 Upper Stages In Production

Stepanov IS/US 16 kgf 16 0.16 Upper Stages Out of Production

DST-200 20 0.20 280 Upper Stages In Production

DST-200A 20 0.20 300 Upper Stages In Production

RDMT-200 20 0.20 255 Upper Stages In Production

SE-5-2/-3 21 272

11D458 40 0.39 252 Upper Stages In Production

Isayev TKS attitude 40 0.39 Upper Stages In Production

Stepanov LK/LOK 40 kgf 40 0.39 Upper Stages Out of Production

RDMT-400 41 0.40 255 Upper Stages In Production

RDMT-400 X 41 0.40 296 Upper Stages Developed 1980's

RDMT-400A 41 0.40 290 Upper Stages Developed 1980's

DMT-600 61 0.60 301 Upper Stages In Production

17D61 300 2.94 326 Upper Stages In Production

KRD-79 315 3.09 Upper Stages In Production

KDU-426 315 3.09 292 Upper Stages In Production

KTDU-417-B 350 3.43 254 Upper Stages Out of Production

Isayev Polet/IS 400 3.92 Upper Stages Out of Production

RD-0225 400 3.92 287 Upper Stages Hardware

KRD-442 447 4.38 Upper Stages In Production

RD-0237 500 4.90 200 Upper Stages Out of Production

RD-866 530 5.20 306 Upper Stages Out of Production

NII 612 kgf 612 6.00 286 Upper Stages Developed

KTDU-80 632 6.19 302 Upper Stages In Production

RD-869 875 8.58 313 Upper Stages Out of Production

YF-23 1,124 11.00 282 260 Upper Stages In Production

RD-857 1,400 13.73 330 Upper Stages Out of Production

RD-0236 1,607 15.76 293 18 Upper Stages Out of Production

11D416 1,670 16.40 Upper Stages Study 1968

KRD-61 1,918 18.80 313 Upper Stages Out of Production

KTDU-425 1,922 18.85 312 Upper Stages Out of Production

KTDU-425A 1,928 18.89 315 Upper Stages Out of Production

S5.92 2,000 19.60 327 Upper Stages Out of Production

S5.98M 2,000 19.62 326 Upper Stages In Production

RD-859 2,045 20.05 312 Upper Stages Hardware

RD-858 2,050 20.10 315 Upper Stages Hardware

RD-864 2,060 20.20 309 Upper Stages Out of Production

RD-868 2,371 23.25 325 Upper Stages Developed 1983-

RD-0231 2,960 29.00 275 First Stages Out of Production

11D430 3,000 29.43 307 Upper Stages In Production

RD-0207 3,150 30.90 297 Upper Stages Developed 1961-64

RD-0214 3,150 30.98 293 Upper Stages In Production

S5.51 3,388 33.20 314 Upper Stages Hardware

11D79 4,500 44.00 Upper Stages In Production

YF-40 5,000 49.00 295 260 Upper Stages In Production

RD-856 5,530 54.23 281 Upper Stages Out of Production

Izotov UR-100 stage 2 vernier 6,000 58.00 Upper Stages Out of Production

Vexin A 7,000 68.60 277 240 Upper Stages Out of Production

Vexin B 7,687 75.40 251 221 First Stages Out of Production

RD-854 7,699 75.50 312 Upper Stages Out of Production

RD-861G 7,796 76.45 325 Upper Stages Developed 1996-

RD-0221 7,954 78.00 330 300 Upper Stages Developed 1965-70

RD-8 7,995 78.40 342 Upper Stages In Production

RD-861 8,026 78.71 317 Upper Stages In Production

Burlak Stage 2 10,000 98.00 330 230 Upper Stages Out of Production

Vexin C 10,108 99.10 251 221 First Stages Out of Production

CZ-1C-3 11,000 107.90 287 258 Upper Stages Developed to 1984

8D725 12,000 117.00 325 Upper Stages Developed 1963-1970

Topaze 12,245 120.10 255 225 Upper Stages Out of Production

RD-0242 12,604 123.60 303 First Stages Developed 1977-83

15D13 13,400 131.40 Upper Stages Study 1968

Izotov LK-700 13,400 131.00 Upper Stages Developed 1966-69

8D423 13,404 131.00 325 Upper Stages Out of Production

R6-117 13,500 132.00 Upper Stages Developed 1964-66

11D423 13,664 134.00 326 Upper Stages Developed 1963-67

RD-862 14,544 142.63 331 Upper Stages Out of Production

RD-0245 21,516 211.00 300 280 First Stages Out of Production

RD-0216 22,330 219.00 313 First Stages Out of Production

RD-0217 22,330 219.00 313 First Stages Out of Production

11D23 23,500 230.50 Upper Stages Study 1968

RD-0235 24,473 240.00 320 Upper Stages In Production

4D10 26,000 255.00 Upper Stages Out of Production

RD-863 28,230 276.84 301 259 First Stages Out of Production

RD-855 29,103 285.40 292 254 First Stages Out of Production

YF-3 29,980 294.00 287 260 Upper Stages In Production

Burlak Stage 1 36,500 360.00 320 270 First Stages Out of Production

RD-0234 53,000 520.00 310 285 First Stages Out of Production

RD-0233 53,000 520.00 310 285 First Stages Out of Production

8D43 57,000 559.00 316 284 First Stages Hardware

RD-0204 57,000 559.00 311 278 First Stages Hardware

RD-0203 57,000 559.00 311 278 First Stages Hardware

RD-0206 59,350 575.50 326 Upper Stages Developed 1961-64

RD-0211 59,360 582.10 327 Upper Stages Out of Production

RD-0213 59,360 582.10 327 Upper Stages In Production

RD-0210 59,360 582.10 327 Upper Stages In Production

RD-0205 62,500 606.40 322 Upper Stages Hardware

RD-0212 62,510 613.00 325 Upper Stages In Production

RD-0244 69,545 682.00 310 280 First Stages Out of Production

Viking 2 70,665 693.00 281 248 First Stages Out of Production

YF-22 73,200 717.80 295 260 Upper Stages In Production

Viking 2B 73,419 720.00 278 248 First Stages In Production

Viking 4 73,518 721.00 296 200 Upper Stages In Production

YF-20A 76,500 750.20 289 259 First Stages In Production

Viking 5C 76,683 752.00 278 248 First Stages In Production

RD-0228 77,000 755.00 Upper Stages Out of Production

RD-0255 77,000 755.00 Upper Stages Out of Production

YF-22A/23A 77,700 762.00 295 270 Upper Stages In Production

YF-22/23 77,700 762.00 295 270 Upper Stages Out of Production

YF-25 80,293 787.40 297 260 Upper Stages In Production

Viking 4B 82,087 805.00 296 210 Upper Stages In Production

YF-20B 83,238 816.30 289 259 First Stages In Production

RD-0243 84,200 825.80 300 First Stages Out of Production

YF-25/23 84,739 831.00 295 260 Upper Stages In Production

RD-250 89,840 881.00 301 269 First Stages Out of Production

RD-252 95,900 940.50 317 Upper Stages In Production

RD-262 96,000 941.00 318 Upper Stages In Production

RD-263 117,777 1155.00 318 293 First Stages Out of Production

RD-268 126,000 1236.00 319 296 First Stages Out of Production

RD-273 126,241 1238.00 296 First Stages Developed 1975-82

RD-253-11D48 166,725 1635.00 316 285 First Stages In Production

11D43 167,425 1642.00 316 285 First Stages Developed 1960-64

RD-254 175,000 1716.00 Upper Stages Developed 1962-66

RD-253-14D14 178,000 1746.00 317 285 First Stages In Production

RD-253 178,000 1745.00 First Stages In Production

RD-253-UR-700 178,000 1745.00 Upper Stages Designed 1964-1968

RD-275 178,000 1745.00 317 285 First Stages In Production

Press Fed 200k 206,803 2028.00 306 200 Upper Stages Design concept 1960's

RD-0202 228,000 2236.00 311 278 First Stages Developed 1961-64

8D43 + 11D43 229,200 2247.45 310 280 First Stages Hardware

RD-0215 250,000 2450.00 310 280 First Stages Developed 1962-65

RD-251 270,000 2643.00 301 269 First Stages In Production

RD-261 309,178 3032.00 301 270 First Stages In Production

RD-264 461,000 4521.00 318 293 First Stages Out of Production

RD-274 504,963 4952.00 296 First Stages Developed 1975-85

RD-270 685,000 6713.00 322 301 First Stages Hardware

Press Fed 1000k 998,639 9793.20 300 240 Upper Stages Design concept 1960's

PF N204/UDMH-2165k 2,165,100 21232.00 267 245 First Stages Design concept 1960's

PF N204/UDMH-2912k 2,911,600 28552.00 267 245 First Stages Design concept 1960's

Press Fed 5748k 5,748,000 56368.00 267 245 First Stages Design concept 1960's

Engine	Thrust(vac) kgf	Thrust(vac) kN	Isp sec	Isp (sea level) sec	Designed for	Status
RDMT-0.4 X	0.0410	0.00040000	290		Upper Stages	In Production
11D431	0.6	0.005880			Upper Stages	In Production
RDMT-8 X	0.8	0.00800	296		Upper Stages	Developed 1980's
Stepanov IS/US 1 kgf	1	0.00980			Upper Stages	Out of Production
RDMT-12	1	0.01200	279		Upper Stages	In Production
17D58E	1	0.01330	247		Upper Stages	In Production
DST-25	3	0.0250	285		Upper Stages	In Production
RDMT-50	5	0.050	255		Upper Stages	In Production
11D446	5	0.052			Upper Stages	In Production
11D445	7	0.065			Upper Stages	In Production
Stepanov LK/LOK 10 kgf	10	0.098			Upper Stages	Out of Production
DST-100A	10	0.100	304		Upper Stages	In Production
RDMT-100	10	0.100	260		Upper Stages	In Production
DST-100	10	0.100	276		Upper Stages	In Production
11D428	11	0.110			Upper Stages	In Production
RDMT-135	14	0.135	260		Upper Stages	In Production
Stepanov IS/US 16 kgf	16	0.16			Upper Stages	Out of Production
DST-200	20	0.20	280		Upper Stages	In Production
DST-200A	20	0.20	300		Upper Stages	In Production
RDMT-200	20	0.20	255		Upper Stages	In Production
SE-5-2/-3	21		272
11D458	40	0.39	252		Upper Stages	In Production
Isayev TKS attitude	40	0.39			Upper Stages	In Production
Stepanov LK/LOK 40 kgf	40	0.39			Upper Stages	Out of Production
RDMT-400	41	0.40	255		Upper Stages	In Production
RDMT-400 X	41	0.40	296		Upper Stages	Developed 1980's
RDMT-400A	41	0.40	290		Upper Stages	Developed 1980's
DMT-600	61	0.60	301		Upper Stages	In Production
17D61	300	2.94	326		Upper Stages	In Production
KRD-79	315	3.09			Upper Stages	In Production
KDU-426	315	3.09	292		Upper Stages	In Production
KTDU-417-B	350	3.43	254		Upper Stages	Out of Production
Isayev Polet/IS	400	3.92			Upper Stages	Out of Production
RD-0225	400	3.92	287		Upper Stages	Hardware
KRD-442	447	4.38			Upper Stages	In Production
RD-0237	500	4.90	200		Upper Stages	Out of Production
RD-866	530	5.20	306		Upper Stages	Out of Production
NII 612 kgf	612	6.00	286		Upper Stages	Developed
KTDU-80	632	6.19	302		Upper Stages	In Production
RD-869	875	8.58	313		Upper Stages	Out of Production
YF-23	1,124	11.00	282	260	Upper Stages	In Production
RD-857	1,400	13.73	330		Upper Stages	Out of Production
RD-0236	1,607	15.76	293	18	Upper Stages	Out of Production
11D416	1,670	16.40			Upper Stages	Study 1968
KRD-61	1,918	18.80	313		Upper Stages	Out of Production
KTDU-425	1,922	18.85	312		Upper Stages	Out of Production
KTDU-425A	1,928	18.89	315		Upper Stages	Out of Production
S5.92	2,000	19.60	327		Upper Stages	Out of Production
S5.98M	2,000	19.62	326		Upper Stages	In Production
RD-859	2,045	20.05	312		Upper Stages	Hardware
RD-858	2,050	20.10	315		Upper Stages	Hardware
RD-864	2,060	20.20	309		Upper Stages	Out of Production
RD-868	2,371	23.25	325		Upper Stages	Developed 1983-
RD-0231	2,960	29.00	275		First Stages	Out of Production
11D430	3,000	29.43	307		Upper Stages	In Production
RD-0207	3,150	30.90	297		Upper Stages	Developed 1961-64
RD-0214	3,150	30.98	293		Upper Stages	In Production
S5.51	3,388	33.20	314		Upper Stages	Hardware
11D79	4,500	44.00			Upper Stages	In Production
YF-40	5,000	49.00	295	260	Upper Stages	In Production
RD-856	5,530	54.23	281		Upper Stages	Out of Production
Izotov UR-100 stage 2 vernier	6,000	58.00			Upper Stages	Out of Production
Vexin A	7,000	68.60	277	240	Upper Stages	Out of Production
Vexin B	7,687	75.40	251	221	First Stages	Out of Production
RD-854	7,699	75.50	312		Upper Stages	Out of Production
RD-861G	7,796	76.45	325		Upper Stages	Developed 1996-
RD-0221	7,954	78.00	330	300	Upper Stages	Developed 1965-70
RD-8	7,995	78.40	342		Upper Stages	In Production
RD-861	8,026	78.71	317		Upper Stages	In Production
Burlak Stage 2	10,000	98.00	330	230	Upper Stages	Out of Production
Vexin C	10,108	99.10	251	221	First Stages	Out of Production
CZ-1C-3	11,000	107.90	287	258	Upper Stages	Developed to 1984
8D725	12,000	117.00	325		Upper Stages	Developed 1963-1970
Topaze	12,245	120.10	255	225	Upper Stages	Out of Production
RD-0242	12,604	123.60	303		First Stages	Developed 1977-83
15D13	13,400	131.40			Upper Stages	Study 1968
Izotov LK-700	13,400	131.00			Upper Stages	Developed 1966-69
8D423	13,404	131.00	325		Upper Stages	Out of Production
R6-117	13,500	132.00			Upper Stages	Developed 1964-66
11D423	13,664	134.00	326		Upper Stages	Developed 1963-67
RD-862	14,544	142.63	331		Upper Stages	Out of Production
RD-0245	21,516	211.00	300	280	First Stages	Out of Production
RD-0216	22,330	219.00	313		First Stages	Out of Production
RD-0217	22,330	219.00	313		First Stages	Out of Production
11D23	23,500	230.50			Upper Stages	Study 1968
RD-0235	24,473	240.00	320		Upper Stages	In Production
4D10	26,000	255.00			Upper Stages	Out of Production
RD-863	28,230	276.84	301	259	First Stages	Out of Production
RD-855	29,103	285.40	292	254	First Stages	Out of Production
YF-3	29,980	294.00	287	260	Upper Stages	In Production
Burlak Stage 1	36,500	360.00	320	270	First Stages	Out of Production
RD-0234	53,000	520.00	310	285	First Stages	Out of Production
RD-0233	53,000	520.00	310	285	First Stages	Out of Production
8D43	57,000	559.00	316	284	First Stages	Hardware
RD-0204	57,000	559.00	311	278	First Stages	Hardware
RD-0203	57,000	559.00	311	278	First Stages	Hardware
RD-0206	59,350	575.50	326		Upper Stages	Developed 1961-64
RD-0211	59,360	582.10	327		Upper Stages	Out of Production
RD-0213	59,360	582.10	327		Upper Stages	In Production
RD-0210	59,360	582.10	327		Upper Stages	In Production
RD-0205	62,500	606.40	322		Upper Stages	Hardware
RD-0212	62,510	613.00	325		Upper Stages	In Production
RD-0244	69,545	682.00	310	280	First Stages	Out of Production
Viking 2	70,665	693.00	281	248	First Stages	Out of Production
YF-22	73,200	717.80	295	260	Upper Stages	In Production
Viking 2B	73,419	720.00	278	248	First Stages	In Production
Viking 4	73,518	721.00	296	200	Upper Stages	In Production
YF-20A	76,500	750.20	289	259	First Stages	In Production
Viking 5C	76,683	752.00	278	248	First Stages	In Production
RD-0228	77,000	755.00			Upper Stages	Out of Production
RD-0255	77,000	755.00			Upper Stages	Out of Production
YF-22A/23A	77,700	762.00	295	270	Upper Stages	In Production
YF-22/23	77,700	762.00	295	270	Upper Stages	Out of Production
YF-25	80,293	787.40	297	260	Upper Stages	In Production
Viking 4B	82,087	805.00	296	210	Upper Stages	In Production
YF-20B	83,238	816.30	289	259	First Stages	In Production
RD-0243	84,200	825.80	300		First Stages	Out of Production
YF-25/23	84,739	831.00	295	260	Upper Stages	In Production
RD-250	89,840	881.00	301	269	First Stages	Out of Production
RD-252	95,900	940.50	317		Upper Stages	In Production
RD-262	96,000	941.00	318		Upper Stages	In Production
RD-263	117,777	1155.00	318	293	First Stages	Out of Production
RD-268	126,000	1236.00	319	296	First Stages	Out of Production
RD-273	126,241	1238.00		296	First Stages	Developed 1975-82
RD-253-11D48	166,725	1635.00	316	285	First Stages	In Production
11D43	167,425	1642.00	316	285	First Stages	Developed 1960-64
RD-254	175,000	1716.00			Upper Stages	Developed 1962-66
RD-253-14D14	178,000	1746.00	317	285	First Stages	In Production
RD-253	178,000	1745.00			First Stages	In Production
RD-253-UR-700	178,000	1745.00			Upper Stages	Designed 1964-1968
RD-275	178,000	1745.00	317	285	First Stages	In Production
Press Fed 200k	206,803	2028.00	306	200	Upper Stages	Design concept 1960's
RD-0202	228,000	2236.00	311	278	First Stages	Developed 1961-64
8D43 + 11D43	229,200	2247.45	310	280	First Stages	Hardware
RD-0215	250,000	2450.00	310	280	First Stages	Developed 1962-65
RD-251	270,000	2643.00	301	269	First Stages	In Production
RD-261	309,178	3032.00	301	270	First Stages	In Production
RD-264	461,000	4521.00	318	293	First Stages	Out of Production
RD-274	504,963	4952.00		296	First Stages	Developed 1975-85
RD-270	685,000	6713.00	322	301	First Stages	Hardware
Press Fed 1000k	998,639	9793.20	300	240	Upper Stages	Design concept 1960's
PF N204/UDMH-2165k	2,165,100	21232.00	267	245	First Stages	Design concept 1960's
PF N204/UDMH-2912k	2,911,600	28552.00	267	245	First Stages	Design concept 1960's
Press Fed 5748k	5,748,000	56368.00	267	245	First Stages	Design concept 1960's

Back to Index

Contact Mark Wade with any corrections, additions, or comments.

Last update 26 June 2002.

Conditions for use of drawings, pictures, or other materials from this site..
© Mark Wade, 2002 .
This web site is sponsored by SpaceBank.com