Fregat Master Thread

[Mighty-T]

In the current printed issue of the French aerospace magazine "Air & Cosmos" there is a small article on an upgrade of the FREGAT for dual-launching the Galileo spacecraft with the Sojuz launcher. According to that article, the new version will include the following changes:

- longer nozzle for the S5-92 motor to improve ISP
- enlarged tanks for +20% more propellant
- upgraded computer ("Bisser-3" -> "Bisser-6")

This will allow the FREGAT to increase its burn by 200s.
Apparently engine testing has already started in September and should last until September 2009.

Has anyone more information about this development? Will it be flight qualified in Russia or in Kourou?

[Cbased]

You can read about Biser-6 here:
http://www.hazard.maks.net/blog/index.php?op=ViewArticle&articleId=45&blogId=1
This is a manufacturer of this computer/control system:
http://www.npcap.ru/index.php?page_id=16 (in russian)

You can also find some useful info about Ariane/Fregat here: http://forum.nasaspaceflight.com/index.php?topic=7201.0

[synchrotron]

Does Lavochkin use the same computer on its spacecraft, or is it only rated for its upper stage?

[Cbased]

I can't say for sure... I know that Biser-4 was used on Buran and that Biser-6 is used on Topol-M. But Lavochkin's spacecrafts - that I don't know.

[anik]

Does Lavochkin use the same computer on its spacecraft, or is it only rated for its upper stage?

NPO Lavochkin enterprise uses Biser computer only on Fregat. They have used Biser-3 computer on this upper stage up to 2007. Since 2007 they use Biser-6 computer on it.

On Elektro-L and Spektr-R spacecrafts NPO Lavochkin enterprise will use computers produced by MOKB Mars Syrov enterprise.

As for Biser computers produced by NPTs AP Pilyugin enterprise, they were used (are using, will be used) on following space rockets and upper stages:

Biser-2 - Zenit-2;
Biser-3 - Proton-M, Zenit-2S, Zenit-2SB40, Zenit-2SB60, DM-SL, Fregat;
Biser-4 - Buran;
Biser-6 - Angara, Fregat, DM-SLB, DM-03.

[Nicolas PILLET]

A picture of Biser-3 is available here :

http://www.kosmonavtika.com/lanceurs/proton/partie2/3photos.html

[synchrotron]

Does Lavochkin use the same computer on its spacecraft, or is it only rated for its upper stage?

NPO Lavochkin enterprise uses Biser computer only on Fregat. They have used Biser-3 computer on this upper stage up to 2007. Since 2007 they use Biser-6 computer on it.

On Elektro-L and Spektr-R spacecrafts NPO Lavochkin enterprise will use computers produced by MOKB Mars Syrov enterprise.

Brilliant.  Thank you.  Will the same team supply the processor for the Fobos-Grunt mission next year?

[anik]

Will the same team supply the processor for the Fobos-Grunt mission next year?

According to Novosti kosmonavtiki forum, control system for Fobos-Grunt will be produced by NPO Lavochkin enterprise.

[Mighty-T]

That seems to be what they now call the Fregat-MT

(see also: http://forum.nasaspaceflight.com/index.php?topic=17577.0)

[Stan Black]

Product 14С44

Fregat	Payload	Start	Rocket	Notes
1001	IRDT	08.02.2000	Soyuz-U PVB А15000-079	Biser-3 computer
1002	DUMSAT	20.03.2000	Soyuz-U PVB
1003	Cluster FM6 / Cluster FM7	16.07.2000	Soyuz-U PVB А15000-069
1004	Cluster FM5 / Cluster FM8	09.08.2000	Soyuz-U PVB А15000-070
1005	Mars Express	02.06.2003	Soyuz-FG Э15000-005
1006	Amos-2	27.12.2003	Soyuz-FG Д15000-008
1007	Galaxy-14	13.08.2005	Soyuz-FG Ж15000-011
1008	GIOVE-B	26.04.2008	Soyuz-FG П15000-016
1009	GIOVE-A	28.12.2005	Soyuz-FG П15000-015
1010	Venus Express	09.11.2005	Soyuz-FG Ж15000-010
1011	METOP-A	19.10.2006	Soyuz-2-1A Ж15000-003
1012	Меридиан 11Л	24.12.2006	Soyuz-2-1A 76033135
1013	COROT	27.12.2006	Soyuz-2-1B П15000-001
1014	Метеор-М 1	17.09.2009	Soyuz-2-1B	Fregat initially allocated to Globalstar
1015	RADARSAT-2	14.12.2007	Soyuz-FG Ц15000-025
1016	Globalstar 65 / 69 / 71 / 72	29.05.2007	Soyuz-FG Ц15000-021	Introduction of Biser-6 computer
1017	Globalstar 66 / 67 / 68 / 70	20.10.2007	Soyuz-FG Ц15000-022

M1005 Mars Express
 One of initial batch of five; two upgraded lithium batteries 9ER14PS-20, 60 Ah each after 0·5 year storage. Used only one attitude control system (ACS) hydrazine tank (-Z axis of Fregat) overfilling it with 11 kg of additional fuel, while the other ACS tank (+Z axis of Fregat) was kept empty, with all hydraulic pipelines re-moved to compensate for Mars Express centre of gravity. For the mission about 20 kg of hydrazine are required only, while each tank has a capacity of 40 kg. The cover material of the Fregat equipment bay was changed from Al-Mg alloy (AMG6) to Mg alloy (Mg-1), with the resulting mass saving of 5 kg. One of the two independent tracking systems of Fregat was removed and for most of the future flights, leaving the one certified for the range of 10,000 km. A satellite navigation unit (SNS) capable of receiving signals from the GPS and GLONASS was installed on the Fregat. The navigation data will go directly to the telemetry system, but is not used in the flight control loop. [News from Moscow № 22/2002]

METOP-A
Fairing 81КС 1000-0 П15000-001
http://www.novosti-kosmonavtiki.ru/nk/forum-pic/Metop/Fregat_Post_flight_report.pdf

[Stan Black]

Article about the programming language
http://www.computerra.ru/readitorial/418507/

[Danderman]

I should mention here that Fregat-SB is not just a Fregat with an extra fuel tank, but rather that the "Fregat" part of the stage is a Fregat-M, which contains small additional propellant tanks affixed to the main tanks, like giant pimples or warts. I don't know if the "M" variant has upgraded avionics. I believe that the "pimple" tanks contain about a ton of additional propellant when they are all added together.

The "MU" "MT" variant of Fregat is in the works, this has similar "pimple" tanks, but they are larger.

The three capacities of Fregat are listed here…
http://www.laspace.ru/rus/fregat_construction.php

МОДЕРНИЗАЦИЯ РАЗГОННОГО БЛОКА «ФРЕГАТ»
http://vestnik.laspace.ru/archives/showproduct/1/2/
http://vestnik.laspace.ru/archives/download/1/2/

This deserves its own thread, so as not to get lost in the mix.

First off, drawings of the 3 variants of Fregat, showing the small and large pimple tanks. Apparently, its possible to fit any of the 3 variants with the large SB drop tank.

The "dry" mass of Fregat for the 3 variants are: 930 kg, 960 kg, and 1050 kg, which means that the small pimple tanks hold in the aggregate 500kg of prop but have a mass of only 30 kg, whereas the large pimple tanks hold 1850 kg with a dry mass of 80 kg.

Again, the three variants of Fregat are the standard, Fregat M and Fregat MU MT.

[Danderman]

The "standard" Fregat, without the pimple tanks, has had some modifications since its first flight in the early 2000s.

First off, there has been an extensive program to reduce the dry mass of the stage, in 3 stages.

The base Fregat had a dry mass of 1100 kg, reduced to 980 kg in 2005, and now to 930 kg (not counting pimple tanks). This was largely accomplished by modernizing the electronics.  The Bizer-3 flight computer was updated to Bizer-6, and the telemetry unit was updated from BR9-TsK-1 to BR91-TsK-M4.  Also, lighter aluminum alloys were used in construction of Fregat.

Lastly, the specific impulse of the engine was increased from 327 to 331 seconds by a 200 mm extension of the engine nozzle. The extension is shown here:

[Stan Black]

What happened to Fregat-MT?

http://www.esa.int/esaCP/SEMCUA3XTVF_index_0.html
http://forum.nasaspaceflight.com/index.php?topic=17577.0
http://forum.nasaspaceflight.com/index.php?topic=15064.0

[Danderman]

Since the old thread's link to an image of the Biser has gone bad, attached is a new image of Biser, I can't tell which version.

[Danderman]

What happened to Fregat-MT?

http://www.esa.int/esaCP/SEMCUA3XTVF_index_0.html
http://forum.nasaspaceflight.com/index.php?topic=17577.0
http://forum.nasaspaceflight.com/index.php?topic=15064.0

The version with the large pimple tanks is MT, not MU:

http://www.b14643.de/Spacerockets_1/East_Europe_1/Soyuz-2/Gallery/Fregat.htm


From the same page, it can be deduced that:

Fregat-SB = Fregat-M plus large drop tank
Fregat-SBU = Fregat MT plus large drop tank. However, it should be noted that although the pimples for this version are larger than the Fregat-M pimples, they may not be exactly the same as the Fregat-MT pimples.

Fregat 2 = Fregat with 2 complete sets of tanks, its unclear whether one of the tank sets can drop off.

All of the current variants of Fregat have the upgraded electronics and other modifications mentioned above.

One other note: for the Glonass K1 launch, we don't know which version of Fregat was used.  It stands to reason that a standard version was launched, because only 1 satellite was the payload, rather than the two sats per launch which is the plan for Soyuz. IF Soyuz-2 launches Glonass from Baikonur, 2 at a time, its not clear which Fregat variant would be used.

Lastly, I have never reviewed earlier Fregat payloads to see if any them used the "M" variant. I suspect that the METOP may have used the "M", but I haven't checked.

[Stan Black]

Good summing up… but can you choose a different name for those tank extensions!

Also telemetry system consists of both БР-91ЦК-М6 and БР-9ЦК-1

Not sure if БР-91ЦК-М6 replaced БР-91ЦК-М4

http://www.novosti-kosmonavtiki.ru/nk/forum-pic/Metop/Fregat_Post_flight_report.pdf

[Phillip Clark]

I am probably wrong, but I have always thought that Fregat might be derived from the descent stage used on the third generation Luna spacecraft (Ye-8 series).   The first use might have been as the Fobos lower propulsion stage which performed the trans-Mars injection burns back in 1988.

[Danderman]

Good summing up… but can you choose a different name for those tank extensions!

Also telemetry system consists of both БР-91ЦК-М6 and БР-9ЦК-1

Not sure if БР-91ЦК-М6 replaced БР-91ЦК-М4

http://www.novosti-kosmonavtiki.ru/nk/forum-pic/Metop/Fregat_Post_flight_report.pdf

For METOP, yes, there was a dual telemetry system as described above, but I am not sure that the dual system is used for all launches. Whether the prime telemetry system is M4 or M6, I can't say, although I do know that M6 has a mass about half that of M4, as it is a modernized version.

The same type of system is used in Soyuz and Progress, from the same factory, or at least that was the case until the new "M" iteration.

[Danderman]

I am probably wrong, but I have always thought that Fregat might be derived from the descent stage used on the third generation Luna spacecraft (Ye-8 series).   The first use might have been as the Fobos lower propulsion stage which performed the trans-Mars injection burns back in 1988.

You are not wrong, although there were some mods between 1988 and 2000.

This begs the question as to the drop tanks used on the Luna series, how do they relate to the current SB drop tank?