Although the "fathers" of the Russian rocketry have been Tzander and Tsiolkowsky, the men that began to take it into practice were (without despising some other collaborators that would stand out later) Isayev, Glushko and Korolev.

-The GIRD (Gruppa Isutcheniya Reacktivnovo Dvisheniya) or Experimental Group for the Reaction Flight, was initiated by Glushko.

-GDL or Gas-Dynamic Laboratory, also cooperated with the development of the first rocket engines.

-The OKB-1 was the one of Dushkin -another pioneer- but when Isayev took it over he had to start almost from scratch. He started by improving the problematic Dushkin D-1-A-1100 engine.

-With time he was involved in the development of the first Russian V-2s. At the end of the 1940's he made the U-2000 engine for the SAM and U-400-2 air-surface missiles.

-During the 50's he continued with engines such as S2.253 until 1958 when the OKB-2 of Sevruk was dissolved and Isayev consolidated in it.

“A.M. Isayev”

-His full name was Aleksei Mikhailovich Isayev.

-He has been collaborating with Korolev (see) in the production of an innumerable series of rocket engines of which we highlight the ones below:

-During the years 1940 to 50, the U-1250, U-2000, U-400-2 and the U-400-10.

-In the 1950's, the S2.721V, S09.29, S2.720, S5.1, S5.44, S2.1100, S2.1150, S5.3M, S2.253 and -A, S2.713, S5.3. The majority destined to missiles like the R-9, R-11, R-13, R-17, R-21 and R-27.

-Most of these engines used AK fuels: Nitric Acid/Amines or Hydrazines.

-Some of these engines were "Clusters" or the sum of several smaller engines, such as the S2.253 on the R-11 or the S2.1150 on the Burya.

-Isayev tried other fuels that were different from those that Glushko used.

-Isayev engines like those of other manufacturers had their official name in addition to the factory one. For example, S5.51 was equivalent to 11D68.

-In the 1960's there was a series of engines for the Yantars, the 11D428, 11D430, 11D431, 11D445, 11D446.

-And the "K" engines. In 1967 the OKB-2 changed its name from the descent station, etc.

-The KTDU-5A were the S5.5 and -A used on the Luna 6. The KRD-417, KTDU-417 and the KRD-61 were used on the Luna 8.

-The KRD-426 and KTDU-35, -53, -80 on the Soyuz T and Progress. The KRD-442 (used between 1972 and 77) as the orbital propulsion engine for the TKS and Mir.

-The KTDU-425 for the Mars. KRD-79 on the Mir. La KTD-66 in Salyut.

“Isayev S5.53 cluster”

-The KDU-414, using UDMH and nitric acid, was used extensively as a maneuvering engine on the Molniya, Mars, Venera and Zond vehicles.

-The KTDU-53 was the S5.53 shown in the illustration. The KVD- engines have been installed on Blok, Proton vehicles etc.

-Very small were the DOT and DOK engines, the -5, -10, -25 and -50 ran on hydrazines.

-The DST (-25, 100, 200 and 600 used N2O4 and UDMH.) Hypergolic fuels without previous ignition.

-Actually, the OKB Isayev Design Office is now the OKB Khimmash.

-They were specialized in minor maneuver engines for corrections, etc. Summarizing:

-DMT-600, hypergolic bipropellant, using N2O4/UDMH.

-The DMT-600-MMH, uses MMH instead of UDMH.

-DOK-10 for the 10N, using hydrazine mono-propellant with iridium as catalyst.

-The DOK-50 for the 50N was like the previous one with more thrust.

-DOT-25, using mono-propellant hydrazine, N2H4.

-The DOT-5 was similar to the previous one.

-The DST-100 used self-inflammable hypergolic bipropellant.

-The same principles for the DST-100A, DST-200, DST-200A and DST-25. The latter with capacity of 300,000 ignitions.

-The Isayev 1 engines were installed on the SAM-V750v.

-The Isayev 2 on the P-15 missile using AK20k/TG02 fuels.

-The Isayev 3 on the R-17 rockets.

“S 5-4 TDU-1 for the Vostok”

-KDU-414 (11D414) were maneuvering engines from the years 1960-65, and were used on the Molniya, Mars, Venera and Zond.

-The KDU-426 (11D426) was used as correction engine on the Salyut T.

-The KRD-442 (11D442) was used on the Kvant, Spektr, Kristall and Priroda as orbital engine.

-The KTDU-425A had the same function on the Venera, Vega and Phobos.

-The KTDU-53 was a maneuvering engine on the Zond.

-The KTDU-5A a maneuvering engine on the Luna-4.

-The KTDU-66 was a maneuvering engine on the Salyut 1.

-S2.253 were installed on the R-11 from 1949 to 1953, using AK20I/Kerosene.

-A derivative one used LOX/kerozine The S2.253A was used on the R-11FM.

-S2.713 were installed on the R-13, from 1956 to 1961.

-S2.720 on the SAM V-755.

-The S5.1 were used on the SAM 217/218 in the 1950's.

-S5.3 on the R-21 (SSN-5) with underwater starter.

-The S5.3M had the same fucntion as the previous one for the R-9.

-The S5.4 was a maneuvering engine on the Vostok and Voshjod.

-The S5.44 was used on the SAM 24.

-The S5-45 was used for trajectory correction on the Zond 1 and Venera 2-8.

-The S5.51 (11D68) was installed on the Soyuz Lok using N2O4/UDMH.

-The S5.80 was used on the Soyuz TM in the year 1977.

-The S5.92 was used by the Phobos.

-The S5-98M was installed on the Rokot 3Briz, Soyuz 2Briz and Proton Briz.

From Appendix 6: This brand specializes in small engines for maneuvering systems, being the Phobos and other vehicles and satellites mainly of the same brand.

“Phobos”

-The Isayev KTDI-425A and the S5.92 are the small engines on the Phobos and the rest of the engines seem from the same family.

“Phobos tanks”

“Main maneuver engines on the Phobos”

-These engines often use hydrazines and are hypergolic or self-igniting.

"Small maneuvering cluster"

-As it is repeated in the main text, Isayev passed to Kimmash. The following project is attributed to this brand and belongs to the Blok vehicle.

"Part of the Russian Blok"

-At the top, one of the typical ring deposits used by the Russians.

-After a new visit to the "Cité de l'Espace" in Toulouse to identify the maneuver rockets on a copy from the Russian MIR station that they expose.

"Habitable module with a battery of maneuvering rocket engines"

"Clear view of two batteries of engines"

"Any corner has a battery of rocket engines"

"Another battery of maneuvering engines"

-The MIR was composed of several modules that were added from 1986 to 1996: Core Module, Services Module, Kvant 1, Kvant2, Kristall, Spectr, Priroda and the Soyuz and Progress vehicle coupling that came and went.

"MIR model in Toulouse"

From Appendix 9: List of engines of this constructor to be used when inserted in the main text and for "cross-reference".

-11D414 (KDU-414), 11D416, 11D417 (KTDU-417), 11D417B (KTDU-417B), 11D425 (KTDU-425), 11D425B (KTDU-425B), 11D426 (KDU-426), 11D442 ((KRD-442), 11D458, 11D49, 11D56 (RD-56), 11D56M (RD-56M), 11D62 (KTDU-35), 11D68 (S5.51).

“11D68, S5.51” (PiP=mw)

-11D69 (RD-218), 14D30 (S5.98M), 17D58E (RDMT-12), 4D10, 5D22 ((SKB-350), 5D25 (S5.44), 5S47.

-And other references: A350 booster and sustainer (SKB-350), DOT-25, DST-100, DST-100A, DST-200, DST-200A, DST-25, DOS-3/4, P-15, Polet / IS, Isayev-218 and R-17, TKS, V-750V, U-1250, U-2000, U-400-10, U-400-2.

-The KDU-414, KDU-426, KRD-417, KRD-442, KRD-61, KRD-79, KTDU-35, KTDU-417 and B, KTDU-417 and A, KTDU-53, KTDU-5A, KTDU-66, KTDU-80, KVD-1 (D-56), KVD-1M and LNG.

-The RO-1, R-100B, (R-101 and R-108), RD-56, RDE-56M, RD-56M LNG.

-And SO9-29, SO9-29-OB, SO9 -502, S2-1150, S2-1100, S2-1200, S2-145, S2-253 and Deriv., -A, S2-713, S2-720 , S2-712V ,, S5-1, S5-19 (KDU-411), S5-23 (11D49), S5-3, S5-35, S5-60, S5-3M, S5-4 (TDU-1) , S5-44, S5-45, S5-5, S5-5A (KTDU-5A), S5-51, S5-53 (KTDU-531), S5-61 (KRD-61), S5.66 (KTDU. 66), S5-79 (KRD-79), S5.80 (KTDU.80), S5.80-1100.0, S5-92, S5-98M, S5-22.

We located an Isayev rocket engine, that by its shape does not seem very successful, that is to say, a beginner and test engine. The U-1250.

"Isayev U-1250 rocket engine"

From Appendix 10: Several of the engines mentioned in the main text have been located.

“Isayev 11D33”

“Isayev 11D33M”

“Isayev S5.92”

“Another view of the Isayev S5-92”

“Isayev S5-92 1n, in height”

-The S5-92 are used on the Fregat, -M and -MT launchers.

“Isayev S2.1150 of the Burya”