 RD-107 engine on display at the Museum of Space and Missile Technology in Saint Petersburg. | |
| Country of origin | Soviet Union Russia |
|---|---|
| Designer | OKB-456 |
| Manufacturer | JSC Kuznetsov[1] |
| Application | Booster/first stage |
| AssociatedLV | R-7 family |
| Predecessor | RD-105 |
| Status | In production |
| Liquid-fuel engine | |
| Propellant | LOX /RP-1 |
| Cycle | Gas-generator |
| Performance | |
| Thrust, vacuum | 1,020 kN (230,000 lbf) |
| Thrust, sea-level | 839 kN (189,000 lbf) |
| Specific impulse, vacuum | 320.2 s (3.140 km/s) |
| Specific impulse, sea-level | 263.3 s (2.582 km/s) |
| Dimensions | |
| Dry mass | 1,190 kg (2,620 lb) |
| References | |
| References | [2][3][4][5][6] |
| Notes | Performance figures are for RD-107A |
TheRD-107 (Russian:Ракетный Двигатель-107,romanized: Raketnyy Dvigatel-107,lit. 'Rocket Engine 107') and its sibling, theRD-108, are a type ofrocket engine used on theR-7 rocket family. RD-107 engines are used in each booster and the RD-108 is used in the central core. The engines have four maincombustion chambers (each with anozzle) and either two (RD-107) or four (RD-108)vernier chambers.
The engines were first developed in the mid-1950s to launch theR-7 Semyorka, the firstintercontinental ballistic missile. The R-7 was later adapted into spacelaunch vehicles and the engines have been improved over several generations. The most recent versions are theRD-107A andRD-108A engines are used to launch theSoyuz-2, which is in active service as of 2024[update].
The RD-107 was designed under the direction ofValentin Glushko at the Experimental Design Bureau (OKB-456) between 1954 and 1957. It usesliquid oxygen andkerosene as propellants operating in agas-generator cycle. As was typical by all the descendants of theV-2 rocket technology, the turbine is driven by steam generated bycatalytic decomposition ofH₂O₂. The steam generator uses solidF-30-P-G catalyst. These are based on a variable sized pellet covered in an aqueous solution ofpotassium permanganate andsodium. Each engine uses four fixed main combustion chambers. The RD-107 has an additional twovernier combustion chambers that canthrust vector in a single plane to supply attitude control. The RD-108 has four verniers to supply full vector control to the Blok-A stage. The single-axleturbopump unit includes the steam driven turbine, an oxidizer pump, a fuel pump, and a nitrogen gas generator for tank pressurization.[3]
The RD-107 engines are used in each of the boosters of theSoyuz-2 rocket, and a single RD-108 is used in the Blok-A stage (the central 1st stage).
One important innovation of this engine was the capability to use variablemixture ratio between fuel and oxidizer. The natural variations in manufacturing between each engine meant that without an active propellant consumption control, each booster could deplete oxygen and fuel at a different rate. This might result in as much as tens of tonnes of unused propellant near the end of the burn. It would generate enormous stress on the structure and cause difficulties in steering due to the mass imbalance. The mixture ratio control system was developed to ensure the simultaneous consumption of propellant mass among the four R-7 boosters.[3][7]
The RD-107 and RD-108 engines are produced at theJSC Kuznetsov plant inSamara, Russia, under the supervision of thePrivolzhskiy branch ofNPO Energomash, also known as theVolga branch.[1][3][5] The Privolzhsky branch was organized as a branch of OKB-456 in 1958, specifically for the manufacture of RD-107 and RD-108 engines. The branch was led by Y.D. Solovjev until 1960, then by R.I. Zelenev until 1975, then by A.F. Udalov until 1978, and is currently led by A.A. Ganin.[8]
Modifications to the RD-107 design have led to production of several distinct versions of the engine:
| Engine | RD-107 | RD-107K | RD-107MM | RD-117 | RD-107A | RD-107A |
|---|---|---|---|---|---|---|
| GRAU index | 8D74 | 8D74K | 8D728 / 8D74M | 11D511 | 14D22 | 14D22KhZ |
| Development | 1954–1959 | Unknown | 1965–1976 | 1969–1975 | 1993–2001 | 2001–2004 |
| Engine cycle | Liquid propellant rocket engine burningRG-1/LOX in agas-generator cycle with the turbine driven by steam generated bycatalytic decomposition ofH2O2 | |||||
| Nozzles | Four main combustion chambers and twovernier thruster combustion chambers for attitude control | |||||
| Combustion chamber pressure | 5.88 MPa (853 psi) | 5.88 MPa (853 psi) | 5.85 MPa (848 psi) | 5.32 MPa (772 psi) | 6 MPa (870 psi) | |
| Thrust, at sea level | 813.98 kN (182,990 lbf) | 818.88 kN (184,090 lbf) | 755.14 kN (169,760 lbf) | 778.68 kN (175,050 lbf) | 839.48 kN (188,720 lbf) | |
| Thrust, in vacuum | 1,000.31 kN (224,880 lbf) | 995.41 kN (223,780 lbf) | 921.86 kN (207,240 lbf) | Unknown | 1,019.93 kN (229,290 lbf) | |
| Specific impulse, at sea level | 256 s (2.51 km/s) | 256.2 s (2.512 km/s) | 257 s (2.52 km/s) | 253 s (2.48 km/s) | 263.3 s (2.582 km/s) | |
| Specific impulse, in vacuum | 313 s (3.07 km/s) | 313.3 s (3.072 km/s) | 314 s (3.08 km/s) | 316 s (3.10 km/s) | 320.2 s (3.140 km/s) | |
| Height | 2,865 mm (112.8 in) | 2,578 mm (101.5 in) | ||||
| Diameter | 1,850 mm (73 in) | |||||
| Intended use | R-7 Sputnik Vostok Voskhod | Molniya | Molniya-M Soyuz | Soyuz-U Soyuz-U2 | Soyuz-FG Soyuz‑ST‑A Soyuz‑ST‑B | Soyuz‑2.1a Soyuz‑2.1b |
| Status | Retired | Retired | Retired | Retired | Retired | In production |
| Ignition | Pyrotechnic | Hypergolic | ||||
| References | Unless otherwise noted:[3][4] | |||||
Similar modifications have led to several distinct versions of the RD-108:
| Engine | RD-108 | RD-108K | RD-108MM | RD-118 | RD-118PF | RD-108A | RD-108A |
|---|---|---|---|---|---|---|---|
| GRAU index | 8D75 | 8D75K | 8D727 / 8D75M | 11D512 | 11D512PF[11] | 14D21 | 14D21KhZ |
| Development | 1954–1959 | Unknown | 1965–1976 | 1969–1975 | 1979–1981 | 1993–2001 | 2001–2004 |
| Engine cycle | Liquid propellant rocket engine burningRG-1/LOX in thegas-generator cycle with the turbine driven by steam generated bycatalytic decomposition ofH2O2 | ||||||
| Propellant | RG-1/LOX | Syntin/LOX[11] | RG-1/LOX | ||||
| Nozzles | Four main combustion chambers and fourvernier thruster combustion chambers for attitude control | ||||||
| Combustion chamber pressure | 5.10 MPa (740 psi) | 5.10 MPa (740 psi) | 5.32 MPa (772 psi) | 5.85 MPa (848 psi) | 5.39 MPa (782 psi) | 5.44 MPa (789 psi) | |
| Thrust, at sea level | 745.33 kN (167,560 lbf) | 745.33 kN (167,560 lbf) | 676.68 kN (152,120 lbf) | 818.88 kN (184,090 lbf) | Unknown | 792.41 kN (178,140 lbf) | |
| Thrust, in vacuum | 941.47 kN (211,650 lbf) | 941.47 kN (211,650 lbf) | 833.60 kN (187,400 lbf) | 1,000.31 kN (224,880 lbf) | Unknown | 921.86 kN (207,240 lbf) | |
| Specific impulse, at sea level | 248 s (2.43 km/s) | 248.2 s (2.434 km/s) | 253 s (2.48 km/s) | 257 s (2.52 km/s) | 263.5 s (2.584 km/s) | 257.7 s (2.527 km/s) | |
| Specific impulse, in vacuum | 315 s (3.09 km/s) | 314.2 s (3.081 km/s) | 316 s (3.10 km/s) | 314 s (3.08 km/s) | Unknown | 320.6 s (3.144 km/s) | |
| Height | 2,865 mm (112.8 in) | ||||||
| Diameter | 1,950 mm (77 in) | ||||||
| Intended use | R-7 Sputnik Vostok Voskhod | Molniya | Molniya-M Soyuz | Soyuz-U | Soyuz-U2 | Soyuz-FG Soyuz‑ST‑A Soyuz‑ST‑B | Soyuz‑2.1a Soyuz‑2.1b |
| Status | Retired | Retired | Retired | Retired | Retired | Retired | In production |
| Ignition | Pyrotechnic | Hypergolic | |||||
| References | Unless otherwise noted:[3][4] | ||||||
Work on the 14D21 and 14D22 engines started in 1986, with a preliminary design completed in 1993. These engines incorporate a new injector head design to increasespecific impulse. The first launch of aProgress cargo spacecraft using a launch vehicle equipped with these engines took place in May 2001. The firsthuman spaceflight launch utilizing these engines took place in October 2002.[5]
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