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Soyuz Fregate
Based on the original 1957 R7 of Korolev and Glushko. The R7 Soyouz has flown over 1729 missions.


Soyuz Fregate  


M1 =303000Kgs

M2 =  28000Kgs.(est)

Height h = 45m



Fregate 4th stage dia 3715mm 

Fregate h = 7700mm.

Fuel (UDMH) unsymmetrical di-methylhydrazine(CH3)2NNH2

and (N2O4) oxydiser.


3rd Stage

2nd Stage core diameter  2.95m

1st  Stage base diameter 8.5m

First stage engines

Four exterior conical R107 engines that fire for 118secs.Each fitted with a small vernier thruster.

One central  R108 that functions for 290secs.and takes over the 2nd stage propulsion.

Fuel for the first three stages is kerosene and liquid oxygen LOX.

To identify stages





The RD107 Engine In the photograph above you can see the clusters expansion nozzles used for launching the Soyuz.

The 4 first stage RD107 engines surround the central RD108.



Soyuz Fregate: the R7 descendent launcher used for launching esa Mars Express June 2003 and Venus Express 2005.

First Stage Comprised of 4 Glushko conical RD107 engines surrounding a cental core RD108 rocket engine. Both use keresene and oxygen.

Each RD107 engine is made up from four bronze combustion chambers fed with pressurised fuel from a common central turbo pump. Note that for each cluster of four there are twin smaller vernier engines that are used for flight adjustment.

The conical RD107 engines seperate from the main core after the first 2 minutes of flight ,once all the fuel has been used; leaving the central RD108 to complete a second stage burn.

The third stage can be seen above the seperation structure that appears to be transparent. The RD0110 engine has 4 nozzles and burns for 240sec

The final or fourth stage Fregate is capable of up to 20 multiple restarts which are used to manouver the payload capsule into the desired orbit. This can be identified as the part in the nose of the rocket with a series of six red balls; 4 contain fuel and 2 flight control instruments at its base.

 Storeable fuel used UDMH with oxidiser  N2O4. Oxidiser to fuel ratio 2.67.


Soyuz Manual esa Starsem




Originally in 1957 the R7 had a structure mass when empty of 18000kgs.

Whilst the Atlas 2 had an empty mass of 5900kgs

With the introduction of light weight alloys and composites the percentage of the structure mass to total fueled mass reduced from 12 to 7 %.

At launch the R7 produced 500 metric tons.f  of  thrust whilst the equivalent US Atlas produced a thrust of 200 metric tons.f.

It is generally accepted that in 1958 the USA rocket engine technology was effectively four years behind that of the Korolev/Glushko R7.

However R7 reliability has become a benchmark in astronautics.

Images above are courtesy of esa starsem

Source and links to Arianespace esa starsem







Soyuz facts  
Lift off mass  M1 304000 Kgs
Propellant mass 279500 Kgs
Structure with Fregate mass   24500 Kgs
Height 43.5 m
Maximum diameter 10.3 m
Thrust (in vacuum)
First stage 4964 KN
Second stage   997 KN
Third stage   298 KN
Fourth stage     19.6 KN
Payload capability (to 832 km) Up to 4300Kgs (with Fregat)



The Fregat upper stage

The Fregat is a fourth stage which has been under development by NPO Lavotchkin since 1992. Its first qualification flight was in January 2000. Although the Fregat is relatively new, each individual component has successfully flown many times. The main engine has already had more than 30 flights, all successful.

Fregat facts
Diameter 3.35 m
Height 1.5 m
Lift off weight 6415 kg
Propellant weight 5350 kg
Fuel Unsymmetrical dimethyl-hydrazine (UDMH)
Oxidizer Nitrogen tetroxide
Main engine thrust 19620 N
Main engine specific impulse 328 seconds


Dont miss the fantastic launch video of Soyuz Galaxy14 mission from Baikonour in Kazakhstan.

Duration 9 mins. First stage seperation 3.52mins video synch. High atmospheric plume due to low external pressure outside the motor expansion nozzle 5.2mins.



New SoyuzMetOp launch film with animation


Selection of Soyuz launch videos



ESA - AOES Medialab


Reference for Menelev's Periodic table to look up chemical properties of liquid oxygen any other fuel.


Reference to discover the properties of  liquid oxygen O2


Reference N2O4. Oxidiser 


Properties of Kerosene

Korolev life history

This site was created on the 15th April 2003

ŠJohn Gwynn and sons2003 

You're welcome to reproduce any material on this site for educational or other non commercial purposes

 as long as you give us proper credit (by referring to "The Water-Rocket Explorer" http://waterocket.explorer.free.fr".