History of Chinas's YF-21/24 rocket engines
The YF-20 is a Chinese liquid rocket engine burning N2O4
and UDMH in an gas generator cycle. It is a basic engine which when mounted
in a four engine cluster forms the YF-21. The high altitude variant
is known as the YF-22 and is paired with YF-23 verniers to form
the YF-24 propulsion module for second stages. Over time several
improvements to the engine performance has been achieved. Finally, the
engine YF-24 of the second stage was in 1991 for the first time replaced
by a significantly upgraded engine version with an extended nozzle on
the main engine (CZ-2E, -2F) . Obviously, the engine YF-24 replaced by
the engine YF-24E for all versions since the year 2002.
The Verniers for the YF-24 engine were used in three variants over time.
The first YF-23 is characterized by a long combustion chamber compared
to the following YF-23B. An uncooled composite nozzle is characteristic
of the current variant YF-23F. This variant has been used latest
since 2012.
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Timeline
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Booster
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Stage 1
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Stage 2 +Verniers (4) |
Launcher CZ-2
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Launcher CZ-3
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Launcher CZ-4
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YF-20B |
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CZ-2E
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CZ-3B |
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YF-20C |
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CZ-2F/SZ, CZ-2F/TG |
CZ-3B+, CZ-3BE, CZ-3C, CZ-3CE |
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4 x YF-20
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= YF-21
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FB-1, CZ-2
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|
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4 x YF-20A
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= YF-21A
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CZ-2C
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CZ-3 |
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4 x YF-20B
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= YF-21B
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CZ-2C+, CZ-2CS, CZ-2D, CZ-2E
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CZ-3+, CZ-3A, CZ-3B |
CZ-4A, CZ-4B |
4 x YF-20C |
= YF-21C |
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CZ-2F/SZ, CZ-2F/TG
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CZ-3A+, CZ-3B+, CZ-3BE, CZ-3C, CZ-3CE |
CZ-4B+, CZ-4C |
CZ-2CS, CZ-2CS-4, CZ-2D-4 |
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YF-22 |
- |
= YF-22 |
FB-1
|
|
|
YF-22 |
+
4x YF-23 |
= YF-24 |
CZ-2
|
|
|
YF-22A |
+
4x YF-23 |
= YF-24A |
CZ-2C
|
,CZ-3 |
|
YF-22B |
+
4x YF-23B |
= YF-24B |
CZ-2C+, CZ-2CS,
CZ-2D
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CZ-3+, CZ-3A,
CZ-3B
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CZ-4A, CZ-4B |
YF-22E ( l.n.) |
+ 4x YF-23B
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= YF-24D |
CZ-2E, CZ-2F/SZ,
CZ-2F/TG
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CZ-3A+,
CZ-3B+, CZ-3BE, CZ-3C
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CZ-4B+,
CZ-4C
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CZ-2CS, CZ-2CS-4, CZ-2D-4 |
YF-22E ( l.n.) |
+ 4x YF-23F
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= YF-24E |
CZ-2F/SZ, CZ-2F/TG |
CZ-3A+, CZ-3BE, CZ-3CE
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CZ-4B+, CZ-4C
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CZ-2CS-4, CZ-2D-4
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DaFY-5-1
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DaFY-6-2 |
DaFY-20-1
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DaFY-21-1
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another term for
engines
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Photo Gallery
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