LOX/LH2

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LOX/LH2

J-2 -

Credit: © Mark Wade. 29,661 bytes. 304 x 445 pixels.

Propellant Formulation: LOX/LH2. Isp: 451.00 vac. Isp: 391.00 sl. Optimum Oxidiser to Fuel Ratio: 4.00. Density: 0.28 g/cc. Temperature of Combustion: 2,985.00 deg K. Ratio of Specific Heats: 1.26. Characteristic velocity c: 2,435 m/s. Isp Shifting: 391. Isp Frozen: 388. Pp Isp Shifting: 109. Mol: 10.00 M.

Oxidiser: LOX. Oxidiser Density: 1.14 g/cc. Oxidiser Freezing Point: -219.00 deg C. Oxidiser Boiling Point: -183.00 deg C.

Liquid oxygen was the earliest, cheapest, safest, and eventually the preferred oxidiser for large space launchers. Its main drawback is that it is moderately cryogenic, and therefore not suitable for military uses where storage of the fuelled missile and quick launch are required. Liquid oxygen, as normally supplied, is of 99.5 percent purity and is covered in the United States by Military Specification MIL-P-25508. High purity liquid oxygen has a light blue colour and is transparent. It has no characteristic odour. Liquid oxygen does not burn, but will support combustion vigorously. The liquid is stable; however, mixtures of fuel and liquid oxygen are shock-sensitive. Gaseous oxygen can form mixtures with fuel vapours that can be exploded by static electricity, electric spark, or flame. Liquid oxygen is obtained from air by fractional distillation. The 1959 United. States production of high-purity oxygen was estimated at nearly 2 million tonnes. The cost of liquid oxygen, at that time, ex-works, was $ 0.04 per kg. By the 1980's NASA was paying $ 0.08 per kg.

Fuel: LH2. Fuel Density: 0.07 g/cc. Fuel Freezing Point: -259.00 deg C. Fuel Boiling Point: -253.00 deg C.

Liquid hydrogen was identified by all the leading rocket visionaries as the theoretically ideal rocket fuel. It had big drawbacks, however - it was highly cryogenic, and it had a very low density, making for large tanks. The United States mastered hydrogen technology for the highly classified Lockheed CL-400 Suntan reconnaissance aircraft in the mid-1950's. The technology was transferred to the Centaur rocket stage program, and by the mid-1960's the United States was flying the Centaur and Saturn upper stages using the fuel. It was adopted for the core of the space shuttle, and Centaur stages still fly today.

In Russia hydrogen fuelled upper stages were designed and developed by the mid-1970's, but the Russians never seem to have found the extra performance to be worth the extra cost. Europe and China developed liquid oxygen/liquid hydrogen engines for upper stages of the Ariane and Long March launch vehicles.

The equilibrium composition of liquid hydrogen is 99.79 per cent parahydrogen and 0.21 per cent orthohydrogen. The boiling point of this composition is -253 deg C. Liquid hydrogen is transparent and without a characteristic odour. Gaseous hydrogen is colourless. Hydrogen is not toxic but is an extremely flammable material. The flammable limits of gaseous hydrogen in air are 4.0 to 75 volume percent.

Hydrogen is produced from by-product hydrogen from petroleum refining and the partial oxidation of fuel oil. The gaseous hydrogen is purified to 99.999+ per cent, and then liquefied in the presence of paramagnetic metallic oxides. The metallic oxides catalyse the ortho-para transformation of freshly liquefied hydrogen. Freshly liquefied hydrogen which has not been catalysed consists of a 3:1 ortho-para mixture and cannot be stored for any length of time because of the exothermic heat of conversion. The delivered cost of liquid hydrogen in 1960 was approximately $ 2.60 per kg. Large-scale production was expected to reduce the cost to $ 1.00 per kg. In the 1980's NASA was actually paying $ 3.60 per kg.

Engines Using Lox/LH2

Eng-engineslink Thrust(vac)-kgf Thrust(vac)-kN Isp-sec Isp (sea level)-sec Designed for Status

RS-52 11 405

RM-1500H 680 400

YF-73 1,125 11.00 425 Upper Stages In Production

RS-71 3,174 430

RD-0126 3,997 39.20 476 Upper Stages Design concept 1993-

HM7-A 6,289 61.70 443 308 Upper Stages Out of Production

HM-10 6,300 61.80 443 Upper Stages Developed 1990's

HM7-B 6,394 62.70 446 310 Upper Stages In Production

RL-10A-3 6,690 65.60 444 Upper Stages Out of Production

RL-10A-5 6,696 64.70 373 316 First Stages Out of Production

AEC 6,801 481

RL-10A-1 6,804 66.70 425 10 Upper Stages Out of Production

RL-10 6,804 66.70 410 10 Upper Stages Out of Production

RD-56 7,100 69.60 462 Upper Stages Developed 1960-77

RL-10A-3A 7,485 73.40 444 Upper Stages In Production

RD-56M 7,503 73.58 461 Upper Stages Developed 1994-

YF-75 8,000 78.50 440 Upper Stages In Production

AMPS-1 8,161 468

ASE 9,068 473

RL-10A-4 9,433 92.50 449 Upper Stages In Production

RL-10B-X 9,524 93.40 470 Upper Stages Design concept 1994

RD-0132 10,000 98.00 469 Upper Stages Design concept 1996-

RD-0126A 10,000 98.00 476 Upper Stages Design concept 1996-

RD-0131 10,000 98.00 467 Upper Stages Design concept 1996-

RD-0133 10,000 98.00 467 Upper Stages Design concept 1996-

RD-0128 10,000 98.00 474 Upper Stages Design concept 1996-

RL-10A-4-2 10,110 99.10 451 Upper Stages In Production

RL-10A-4-1 10,110 99.10 451 Upper Stages In Production

RD-0146 10,197 100.00 470 Upper Stages Design concept 1998-

RL-10A-5KA 10,247 398 352 First Stages Design 1992

LE-5 10,500 103.00 450 Upper Stages In Production

RL-10B-2 11,222 110.00 462 Upper Stages In Production

RL-10C-X 11,300 110.80 450 Upper Stages Design concept 1994

LE-5A 12,390 121.50 452 Upper Stages In Production

HIMES 14,000 137.30 452 340 Upper Stages Study -1998

LE-5B 14,000 137.00 447 Upper Stages In Production

Truax LH2 15,000 147.10 425 306 Upper Stages Design concept 1982

RL-10C 15,873 155.70 450 Upper Stages In Production

MB-60 27,200 467

RL-50 29,500 290.00 472 Upper Stages Development

LH2-80k 36,274 355.70 425 306 Upper Stages Study 1959

RD-57 40,000 392.00 457 Upper Stages Developed 1960-77

RD-54 40,000 392.00 440 Upper Stages Developed 1960-75

RD-57A-1 40,279 395.00 460 Upper Stages Developed 1995-98

RD-57M 40,483 397.00 461 Upper Stages Developed 1960-74

MBB-ATC500 45,000 441.30 460 409 First Stages Study 1980

LR-87 LH2 68,000 667.00 350 Upper Stages Out of Production

J-2T-200K 90,686 889.30 435 300 Upper Stages Study NASA 1966

J-2-SL 101,634 996.70 390 275 First Stages Study 1966

J-2 105,352 1,033.10 421 200 Upper Stages Out of Production

Vulcain 109,619 1,075.00 431 326 First Stages In Production

LE-7 109,925 1,078.00 446 349 First Stages In Production

LE-7A 112,000 1,098.00 440 338 First Stages In Development

Aerospike Annular Booster 113,358 450

J-2T-250K 113,358 1,111.60 441 290 Upper Stages Study NASA 1966

J-2S 121,066 1,187.00 426 200 Upper Stages Developed 1965-1969

XRS-2200 121,600 1,192.00 439 339 First Stages In Production

ATCRE 130,524 1,280.00 490 409 Upper Stages Study -1985

Vulcain 2 132,563 1,300.00 440 318 First Stages Developed 1990's

HG-3-SL 141,500 1,387.00 450 360 First Stages Study 1966

HG-3 142,831 1,400.70 451 280 Upper Stages Developed 1960's

SSME Study 156,550 1,535.20 459 359 First Stages Study 1970

Plug-Nozzle SASSTO 160,600 1,574.90 459 359 First Stages Study 1966

Helios Stage 1 170,000 1,667.00 400 340 First Stages Study, Ehricke, 1960

Toroidal 400k 181,400 1,778.00 447 200 Upper Stages Design concept 1990's

RD-0120M 200,000 1,961.00 455 372 First Stages Hardware

RD-0120 200,000 1,961.00 455 359 First Stages Out of Production

NK-35 200,000 1,960.00 Upper Stages Design 1972

NK-15VM 200,000 1,960.00 Upper Stages Developed 1965

Mustard 220,000 2,157.40 405 300 First Stages Study 1967

RS-2200 224,540 2,201.00 455 347 Upper Stages In Production

SSME 232,301 2,278.00 453 363 First Stages In Production

RD-0122 235,860 2,313.00 461 Upper Stages Developed 1990-

SSME Demonstrator Booster 249,400 465

Toroidal 560k 254,020 2,491.00 447 200 Upper Stages Design concept 1990's

STME 294,703 2,890.00 431 365 First Stages Developed -1990

RS-68 337,807 3,312.00 420 365 First Stages In Production

SSME Plus 380,221 3,728.70 467 385 First Stages Study 1970

Plug-Nozzle SSME 380,221 3,728.70 485 412 First Stages Study 1970

PW 1000000 lb LH2 454,500 4,457.00 425 354 First Stages Study 1988

M-1 544,118 5,335.90 428 310 Upper Stages Developed 1960's

HP-1 666,541 6,536.00 451 379 First Stages Study 1963

Plug-Nozzle J-2 700,000 6,864.60 425 330 First Stages Study 1993

CD Module 750,708 7,361.00 420 377 First Stages Design concept 1960's

Chamber/single nozzle 1,349,250 13,231.00 455 365 First Stages Design concept 1960's

Toroid FD 2,041,000 20,015.00 455 Upper Stages Study 1963

Plug-Nozzle Pegasus 2,440,000 23,928.00 459 359 First Stages Study 1966

L-5.25H 2,789,000 27,350.00 410 350 First Stages Study General Dynamics 1963

L-5.00H 3,129,000 30,684.00 428 310 First Stages Study General Dynamics 1963

Plug-Nozzle SERV 3,261,105 31,980.20 455 367 First Stages Study 1970

5 mlbf 4,217,750 41,361.00 410 345 First Stages Study 1963

Plug-Nozzle Rombus 10,400,000 101,988.00 459 359 First Stages Study 1966

L6H 12,517,000 122,748.00 439 382 First Stages Study 1963

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Last update 3 May 2001.
Contact Mark Wade with any corrections or comments.
Conditions for use of drawings, pictures, or other materials from this site..
© Mark Wade, 2001 .

Eng-engineslink	Thrust(vac)-kgf	Thrust(vac)-kN	Isp-sec	Isp (sea level)-sec	Designed for	Status
RS-52	11		405
RM-1500H	680		400
YF-73	1,125	11.00	425		Upper Stages	In Production
RS-71	3,174		430
RD-0126	3,997	39.20	476		Upper Stages	Design concept 1993-
HM7-A	6,289	61.70	443	308	Upper Stages	Out of Production
HM-10	6,300	61.80	443		Upper Stages	Developed 1990's
HM7-B	6,394	62.70	446	310	Upper Stages	In Production
RL-10A-3	6,690	65.60	444		Upper Stages	Out of Production
RL-10A-5	6,696	64.70	373	316	First Stages	Out of Production
AEC	6,801		481
RL-10A-1	6,804	66.70	425	10	Upper Stages	Out of Production
RL-10	6,804	66.70	410	10	Upper Stages	Out of Production
RD-56	7,100	69.60	462		Upper Stages	Developed 1960-77
RL-10A-3A	7,485	73.40	444		Upper Stages	In Production
RD-56M	7,503	73.58	461		Upper Stages	Developed 1994-
YF-75	8,000	78.50	440		Upper Stages	In Production
AMPS-1	8,161		468
ASE	9,068		473
RL-10A-4	9,433	92.50	449		Upper Stages	In Production
RL-10B-X	9,524	93.40	470		Upper Stages	Design concept 1994
RD-0132	10,000	98.00	469		Upper Stages	Design concept 1996-
RD-0126A	10,000	98.00	476		Upper Stages	Design concept 1996-
RD-0131	10,000	98.00	467		Upper Stages	Design concept 1996-
RD-0133	10,000	98.00	467		Upper Stages	Design concept 1996-
RD-0128	10,000	98.00	474		Upper Stages	Design concept 1996-
RL-10A-4-2	10,110	99.10	451		Upper Stages	In Production
RL-10A-4-1	10,110	99.10	451		Upper Stages	In Production
RD-0146	10,197	100.00	470		Upper Stages	Design concept 1998-
RL-10A-5KA	10,247		398	352	First Stages	Design 1992
LE-5	10,500	103.00	450		Upper Stages	In Production
RL-10B-2	11,222	110.00	462		Upper Stages	In Production
RL-10C-X	11,300	110.80	450		Upper Stages	Design concept 1994
LE-5A	12,390	121.50	452		Upper Stages	In Production
HIMES	14,000	137.30	452	340	Upper Stages	Study -1998
LE-5B	14,000	137.00	447		Upper Stages	In Production
Truax LH2	15,000	147.10	425	306	Upper Stages	Design concept 1982
RL-10C	15,873	155.70	450		Upper Stages	In Production
MB-60	27,200		467
RL-50	29,500	290.00	472		Upper Stages	Development
LH2-80k	36,274	355.70	425	306	Upper Stages	Study 1959
RD-57	40,000	392.00	457		Upper Stages	Developed 1960-77
RD-54	40,000	392.00	440		Upper Stages	Developed 1960-75
RD-57A-1	40,279	395.00	460		Upper Stages	Developed 1995-98
RD-57M	40,483	397.00	461		Upper Stages	Developed 1960-74
MBB-ATC500	45,000	441.30	460	409	First Stages	Study 1980
LR-87 LH2	68,000	667.00		350	Upper Stages	Out of Production
J-2T-200K	90,686	889.30	435	300	Upper Stages	Study NASA 1966
J-2-SL	101,634	996.70	390	275	First Stages	Study 1966
J-2	105,352	1,033.10	421	200	Upper Stages	Out of Production
Vulcain	109,619	1,075.00	431	326	First Stages	In Production
LE-7	109,925	1,078.00	446	349	First Stages	In Production
LE-7A	112,000	1,098.00	440	338	First Stages	In Development
Aerospike Annular Booster	113,358		450
J-2T-250K	113,358	1,111.60	441	290	Upper Stages	Study NASA 1966
J-2S	121,066	1,187.00	426	200	Upper Stages	Developed 1965-1969
XRS-2200	121,600	1,192.00	439	339	First Stages	In Production
ATCRE	130,524	1,280.00	490	409	Upper Stages	Study -1985
Vulcain 2	132,563	1,300.00	440	318	First Stages	Developed 1990's
HG-3-SL	141,500	1,387.00	450	360	First Stages	Study 1966
HG-3	142,831	1,400.70	451	280	Upper Stages	Developed 1960's
SSME Study	156,550	1,535.20	459	359	First Stages	Study 1970
Plug-Nozzle SASSTO	160,600	1,574.90	459	359	First Stages	Study 1966
Helios Stage 1	170,000	1,667.00	400	340	First Stages	Study, Ehricke, 1960
Toroidal 400k	181,400	1,778.00	447	200	Upper Stages	Design concept 1990's
RD-0120M	200,000	1,961.00	455	372	First Stages	Hardware
RD-0120	200,000	1,961.00	455	359	First Stages	Out of Production
NK-35	200,000	1,960.00			Upper Stages	Design 1972
NK-15VM	200,000	1,960.00			Upper Stages	Developed 1965
Mustard	220,000	2,157.40	405	300	First Stages	Study 1967
RS-2200	224,540	2,201.00	455	347	Upper Stages	In Production
SSME	232,301	2,278.00	453	363	First Stages	In Production
RD-0122	235,860	2,313.00	461		Upper Stages	Developed 1990-
SSME Demonstrator Booster	249,400		465
Toroidal 560k	254,020	2,491.00	447	200	Upper Stages	Design concept 1990's
STME	294,703	2,890.00	431	365	First Stages	Developed -1990
RS-68	337,807	3,312.00	420	365	First Stages	In Production
SSME Plus	380,221	3,728.70	467	385	First Stages	Study 1970
Plug-Nozzle SSME	380,221	3,728.70	485	412	First Stages	Study 1970
PW 1000000 lb LH2	454,500	4,457.00	425	354	First Stages	Study 1988
M-1	544,118	5,335.90	428	310	Upper Stages	Developed 1960's
HP-1	666,541	6,536.00	451	379	First Stages	Study 1963
Plug-Nozzle J-2	700,000	6,864.60	425	330	First Stages	Study 1993
CD Module	750,708	7,361.00	420	377	First Stages	Design concept 1960's
Chamber/single nozzle	1,349,250	13,231.00	455	365	First Stages	Design concept 1960's
Toroid FD	2,041,000	20,015.00	455		Upper Stages	Study 1963
Plug-Nozzle Pegasus	2,440,000	23,928.00	459	359	First Stages	Study 1966
L-5.25H	2,789,000	27,350.00	410	350	First Stages	Study General Dynamics 1963
L-5.00H	3,129,000	30,684.00	428	310	First Stages	Study General Dynamics 1963
Plug-Nozzle SERV	3,261,105	31,980.20	455	367	First Stages	Study 1970
5 mlbf	4,217,750	41,361.00	410	345	First Stages	Study 1963
Plug-Nozzle Rombus	10,400,000	101,988.00	459	359	First Stages	Study 1966
L6H	12,517,000	122,748.00	439	382	First Stages	Study 1963