FEDERAL state unitary enterprise “Experimen- tal design bureau “Fakel” (hereafter EDB Fakel)is one of the world leaders in development and manuf acturing of stationary plasma thrusters (SPT)and low thrust propulsion units on their basis, the leading Russian enterprise in development and manufacturing of thermal catalytic (hydrazine)thrusters and propulsion units on their basis, as well as plasma sources for use in space and on ground.
EDB Fakel was established in 1955 as a “Pro- pulsion laboratory” of the Russian Academy of Sci- ences and in 1962 the enterprise was assigned with the status of an experimental design bureau.


By now 303 spacecraft (S/C) with Fakel’s prod- ucts have been launched in orbit. More than 50 % of S/C in Russia is equipped with Fakel’s thrusters and their share at the world market is more than 10 %. A steady tendency to increase these values is discernible.
The enterprise’s products are as good as domestic and Western analogs with respect to their characteristics and stand at the level of the best developments in the world.
Today EDB Fakel closely co-operates with many Russian enterprises such as ISS-Reshetnev Company, Rocket and Space Corporation Energia, Khrunichev State Research and Production Space Center, Research and Production Corpora- tion VNIIEM, as well as Western companies such as Airbus D&S, TAS, OHB, IAI, RUAG and Space Systems Loral. According to the latest data, about 40 % of S/C made by Space Systems Loral use thrusters produced by EDB Fakel.
Development, testing and manufacturing of sta- tionary plasma thrusters were started at EDB Fakel in the late 60’s of the past century. The experimen- tal operation of the first thruster of this type, that was the SPT-60, was successfully conducted as a part of the electric propulsion system Aeolus-1 on board “Meteor” spacecraft in 1971. The discharge power was about 400 W and this thruster had rela- tively low characteristics with the efficiency about 30 %. Further research of physical and operation- al processes of the SPT resulted in a significant increase of thrust, specific and life time character- istics. As of today, a parametric row of the SPTs has been developed at EDB Fakel with the pow- er of up to 25 kW. They are recognized as the best thrusters in their class in the world and actively used on board Russian and Western S/C, they are highly effective and reliable space hardware.
As of early 2019, there were 615 Fakel’s SPTs in flight operation:

SPT-50, SPT-60  24; 
SPT-70 132;
SPT-100 436;
SPT-140 23.

 

Currently, the SPTs are used not only in orbit- al spacecraft constellations attitude control and station keeping systems, but there is also a sig- nificant increase in the use of the SPTs for a S/C transfer from a support orbit to operational orbit. For the first time a S/C transfer plan was valida- ted in flight using Fakel’s electric propulsion sys- tem in the course of the launching campaign for the Express-AM5 satellite. The 72-day transfer phase was combined with the target orbital posi- tion maneuver. A correction unit equipped with the SPT-100 was used as the electric propulsion system for this transfer; this correction unit is a part of the regular set of station keeping system intended for maneuvers along the orbit and for orbital position keeping throughout the active life time.
It should be noted that the SPT-100 is one of the best thrusters in its class in terms of output charac- teristics, reliability and flight heritage. It was quali- fied both for Russian and Western customers.

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The first S/C equipped with the SPT-100 was launched in 1994. Since 1995 it has been successfully used in the station keeping systems on a series of Rus- sian geostationary communication satellites and since 2003 the SPT-100 has been operated on Western geostationary satellites such as Inmarsat, Intelsat-X, IPSTAR-II, Telstar-8 and others. Accor- ding to Space Systems Loral, the total operating time of the SPT-100 thrusters on Space Systems Loral’s S/C has exceeded 100,000 hrs.
The idea of transferring was further evolved at EDB Fakel by development of several modifi- cations of higher power SPT-140 dimension-type thrusters up to 6 kW with a thrust which was by approximately 3 times higher than thrust of the SPT-100 with approximately identical specif- ic impulse. Currently, the thrusters qualification for flight testing, as required by Russian custom- ers, has been completed and these thrus ters are already delivered for Western customers. The SPT-140D has accumulated about 18,500 hrs life time – a record for EDB Fakel’s thrusters. In 2018 the SPT-140D was used for the first time for S/C raising from a transfer orbit to a geostationary orbit and for keeping S/C on its station point on a geostationary orbit on board the telecommu- nication satellite Eutelsat 172B. Accor ding to the media, Eutelsat 172B with Fakel’s thrusters on board has broken the record of the shortest time spent for transfer orbit. It took only 4 months from launch to reach a geostationary orbit. The amount of propellant consumed during the satel- lite orbit raising phase was by 6 times less than for satellites with chemical thrusters on board. Eutelsat 172B is the first European all-electric propulsion system satellite. The tendency of using SPTs with such a power both on Western and domestic S/C will most likely manifest itself more significantly in the future. All-electric pro- pulsion system S/C will completely take the main share of space market in the world.
In order to optimize propulsion systems by solving the tasks of station keeping and orbit raising using one thruster, EDB Fakel in cooperation with RUAG (Switzerland) has developed ITU-100 and ITU-140 (Integrated Thruster Units)intended to generate required thrust forces in the process of a S/C operational orbit formation and orbit maintenance within required li mits during a S/C operation in space environment. The ITU-100 and ITU-140 are a ready-made and perspective solution for propulsion systems integ ration based on the SPT-140, SPT-100 and Thrusters orientation mechanism (TOM). The ITU-100 and ITU-140 have successfully passed qualification test.
A continuous expansion in the fields of appli- cation of the SPTs in S/C attitude control and sta- tion keeping, in transportation tasks and in car- rying out other maneuvers in space leads to the need to engineer an SPT with higher thrust, spe- cific and life time characteristics in combination with reduced mass-dimension characteristics while optimizing manufacturing lead time, includ- ing high-volume production within a short time. EDB Fakel is working to modify the existing thrus- ters (SPT-50, SPT-70, SPT-100B and SPT-140) and to create new models, which are aimed at solving the following main tasks:
a) provide higher thrust and specific parame- ters and a possibility to have an efficient operation in several modes by optimizing parameters and topology of the magnetic field;
b) increase life time characteristics (up to 15,000 hrs and more) at stable thrust values during a long-time operation;
c) reduce plasma plume divergence;
d) increase strength characteristics;
e) introduce into the thrusters design results
of new developments, structural materials and components (emitters, ceramics, wires), increase design manufacturability to reduce labor costs and product price;
е) consider a possibility to operate using alter- native propellants (krypton, iodine and others).
The modified SPT-50M thrusters are already delivered by EDB Fakel in frames of the interna- tional space project “OneWeb” where a large orbital constellation (700 spacecraft) is planned to

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be placed on a low-earth orbit to provide internet coverage all over the Earth. The prototype of this thruster, that is the SPT-50, which was designed back in the 70’s and qualified upon requirements of a Russian customer, is still successfully used as a part of the EPS on a S/C intended for the Earth remote sensing. The modification enabled increase the thrust by ~5 %, specific impulse by
8 % and life time characteristics by 2 times mini- mum.
As far as EDB Fakel’s activities in the field of the Earth remote sensing concerned, it should be stressed that a successful use of informa- tion received from space depends not only on space information acquisition sources, but also on ground infrastructure for space data reception, processing, storage and further use of space- based data. In order to develop a Integrated Geo- graphically Distributed Information System of Earth Remote Sensing (ETRIS) from space a Western regional center was established for reception, processing and distribution of space information on the basis of the ground tracking station loca- ted at EDB Fakel in September 2015.
The SPTs are also considered perspective for interplanetary flights and deep space research missions, but a comparatively low thrust of such thrusters demands using a configuration of se ver- al thrusters on a S/C to provide a S/C velocity increment what, in its turn, will require a high on-board electrical power. Today the idea of a space tug is widely developed, what will allow transporting payload to a target point. Such a tug will also be used to transfer heavy S/C to a

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geostationary orbit and deliver scientific and research stations to planets and, probably, pro- vide manned missions in the future. Space tugs, currently developed by various Western compa- nies, are designed to apply a power higher than 50 kW. A powerful highly efficient and reliable propulsion system will be needed.
These days EDB Fakel works to design a high power stationary plasma thruster of the SPT-230 type able to operate in the power range from 10 to 25 kW. Feasibilities are also considered to design electric propulsions with the power of 100 kW and more alternative design schemes.
Considering a longer active life time of modern S/C and a need to solve transportation tasks for a deep space, a search for alternative propellants becomes relevant. The price of such propellants is significantly lower than the price of xenon cur- rently used. Since 2018, Fakel has been actively conducting research testing of various dimension types SPTs using krypton. Moreover, EDB Fakel takes part in the works conducted by the Rocket

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and Space Corporation Energia on the SPT deve- lopment using iodine. Iodine parameters such as atomic mass and ionization potential, which are close to the parameters of xenon, enable using the SPT typical design with minor modifi- cations. A space experiment named “Ostrovskiy” is planned for the future to perform flight tests of an SPT-based experimental propulsion system on the transport cargo vehicle Progress.
Research works were started in 2018 on a feasi- bility to design an ultra-low thrust SPT for Cubesat- nano-class spacecraft and an experimental system to test them on ground in space conditions.
It should be noted that Fakel also delivers atti- tude control and station keeping systems based on thermal catalytic thrusters for S/C. The first thermal catalytic thrusters by EDB Fakel were used in flight in the 80’s of the past century. Since that time more than 3,590 thermal catalytic thrus- ters have been operated in domestic and wes- tern spacecraft propulsions systems. EDB Fakel’s hydrazine thermal catalytic thrusters are capable to operate in lower pressure ranges compared to the western analogs – the inlet pressure in the range from 1,000 down to 168 kPa. The minimum nominal thrust is 0.05N.
All the thrusters are integrated in thruster units. At present time EDB Fakel works on extension of its thermal catalytic thrusters line and modifica- tion of existing thrusters. The available scientific reserves enable producing also new high effective models with the nominal thrust from 0.01 to 50 N. Besides, a world tendency in thermal catalytic thrusters development is a switch from the tradi- tional high toxic compounds to so-called “green” fuels, which are substances of a significantly lower environmental hazard class. Considering this ten- dency, as well as aimed at extending the products nomenclature, Fakel works on designing and fur- ther extension of thrusters assortment operating on “green” fuel.
Today, more than 1,000 people work at EDB Fakel.
The enterprise is located at 3 facilities.
The total area is 57,000 square meters.
An analysis of the enterprise internal environment shows that quantity and qualification of the personnel, level of production and test facilities instrumentation and products manufacturing tech- nology currently enable meet contractual commit- ments to users.
EDB Fakel has a unique and unified facility for full-scale research, development, manufacturing, testing and operation of electric thrusters, ther- mal catalytic thrusters and propulsion systems on their basis.
The Quality Management System (QMS) was developed, implemented and now used at the enterprise. This system applies to designing, modernization, repair, tests, technical support in operation of low-thrust electrical thrusters and thermal catalytic thrusters, their component parts, propulsion units and propulsion systems and components for military, scientific and social-eco- nomic purpose S/C. The QMS was certified in 2001 for compliance with the requirements of the ISO 9000 international standards. The validity of certificates of conformance is approved by annu- al audits and periodical re-certifications. The QMS has been audited by Russian and Western cus- tomers for many times.
Currently, the enterprise’s production and test facilities have technological and unique test stand equipment to perform all types of works for designing and serial production of SPTs, thermal catalytic thrusters and propulsion systems on their basis. For the nearest future a continuous batch production of 33 SPTs per month is planned.
EDB Fakel’s main technological equipment consists of 474 units that is testing, metal-work- ing, welding, thermal treatment equipment and other machinery (galvanic, lacquer and paint, wood-working). The equipment fleet was arranged according to the requirements to ensure a full complex of various technological operations and is maintained in a satisfactory state and pro- vides for fulfillment of technological operations in a full scope.
The enterprise possesses diverse technological processes specific for EPS, what is stipulated by a variety of materials and miniature parts used:
• machining of miniature parts from hard-to-machine materials (ceramics, refractory metals and alloys);
• high-temperature vacuum brazing of metal to ceramics joints and capillary tubes;
• electron beam, laser and diffusion welding of refractory metals and alloys;
• application of protective ceramic coatings by plasma sputtering method;
• bonding of high-temperature SPT joints and preparation of adhesive formulation;
• high-precision electro-erosion holes piercing;• magnetic-pulse stamping;
• surface preparation and providing for cleanli-
ness of propellant supply lines working surfaces;
• adjustment and control for angular and linear positions of thrusters and thruster units;
• climatic, mechanical, thermal vacuum and fi ring test of thrusters and thruster units.
Quite a number of technologies is patented
(heat treatment of soft magnetic alloys, special coatings and adhesives ensure products opera- tion in open space conditions).
EDB Fakel continuously works to improve the technologies and implement new ones aimed at production costs and labor intensity reduction, parts, assembly units and propulsion systems lead time reduction by providing a higher product qua- lity and reliability, as well as by a complete tech- nological independence for production (including import substitution).
In perspective, EDB Fakel plans to modernize its production, technological and test facilities to continue developing the enterprise and desig ning the demanded high-effective space hardware, space materials and technologies.chine materials (ceramics, refractory metals and alloys);
• high-temperature vacuum brazing of metal to ceramics joints and capillary tubes;
• electron beam, laser and diffusion welding of refractory metals and alloys;
• application of protective ceramic coatings by plasma sputtering method;
• bonding of high-temperature SPT joints and preparation of adhesive formulation;
• high-precision electro-erosion holes piercing;• magnetic-pulse stamping;
• surface preparation and providing for cleanli-
ness of propellant supply lines working surfaces;
• adjustment and control for angular and linear positions of thrusters and thruster units;
• climatic, mechanical, thermal vacuum and fi ring test of thrusters and thruster units.
Quite a number of technologies is patented
(heat treatment of soft magnetic alloys, special coatings and adhesives ensure products opera- tion in open space conditions).
EDB Fakel continuously works to improve the technologies and implement new ones aimed at production costs and labor intensity reduction, parts, assembly units and propulsion systems lead time reduction by providing a higher product qua- lity and reliability, as well as by a complete tech- nological independence for production (including import substitution).
In perspective, EDB Fakel plans to modernize its production, technological and test facilities to continue developing the enterprise and desig ning the demanded high-effective space hardware, space materials and technologies.

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