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Elektro-L1 weather satellite Launched on Jan. 20, 2011, the Elektro-L No. 1 meteorological satellite became the first major spacecraft developed in the post-Soviet Russia.
Key components of the Elektro-L satellite. Copyright © 2009 Anatoly Zak
Launch preparations In the first half of the 2000s, the launch of the original Elektro-L spacecraft was promised in 2006 but the mission was subsequently delayed to June 2007, the fourth quarter of 2007 and November 2008. On the night of January 16, 2009, the Zenit rocket intended for the Elektro mission arrived to Baikonur, followed by the shipment of the Fregat upper stage on April 4 of the same year. However in the second half of 2009, the satellite was still waiting for the delivery of its key instrument - the MSU-GS multi-spectral sensor - and the launch of the satellite was then unofficially projected for no earlier than April 2010. In March 2010, Roskosmos confirmed previous unofficial reports that the MSU-GS instrument would have to be modified to account for problems encountered in the operation of a similar instrument onboard the Meteor-M No. 1 satellite. This delay temporarily pushed the launch of Elektro-L behind the more complex Spektr-R spacecraft. Since both satellites were based on the untested Navigator platform, this schedule change put more risk on the more expensive and valuable Spektr-R mission. As of June 2010, the official schedule called for the Elektro-L launch in December 2010, or about a month after Spektr-R. However the launch of the radio observatory was ultimately delayed to the Spring of 2011. At the end of January - beginning of February 2010, the flight version of the Elektro-L satellite successfully went through electrical tests at the VK-600 vacuum chamber at NITs RKTs facility in Peresvet near Moscow. At the beginning of November, the Fregat upper stage was loaded with propellant at the fueling station at Site 31. After last minute delays in delivery of Elektro-L to the launch site from November 22 and 30, the spacecraft finally departed for Baikonur on Dec. 1, 2010. The launch preparation campaign started at Site 31 on the next day. During December 8-11, the satellite was loaded with propellant and five days later the spacecraft was integrated with the Fregat-SB upper stage. However, in the wake of a high-profile failure of the Proton rocket with GLONASS satellites in December 2010, the launch of Elektro-L then scheduled for Dec. 25, 2010, at 15:27 Moscow Time was put in limbo again. In the middle of the day on Dec. 16, 2010, an order came to Baikonur from the head of the Russian space agency to stop all preparations for launch, even though there were no apparent problems in the campaign itself. Officials were reportedly re-checking all the procedures, especially related to a brand-new Fregat-SB stage. 24 hours later, the work on the payload section of the rocket, known as KGCh, was allowed to proceed, but not on the satellite itself. The launch had to be delayed until January 15-20, 2011, which is after Orthodox christmas holidays in the first half of the month. Critics said that the satellite with full load of propellant onboard had to be essentially mothballed until January 10, since there were no technical problems in the launch campaign. One positive fallout from the delay was the fact that a critical post-launch orbit corrections would no longer fall on pre-new year eve on Dec. 30-31, 2010. By December 24, the new launch window for Elektro-L was narrowed down to Jan. 20, 2011. Work did resume on January 11, as the satellite with the upper stage was lowered into horizontal position and integrated with the payload fairing. On January 17, the Zenit rocket intended for the mission was placed on its transporter/erector. The next day, the launch vehicle with the satellite was rolled out from the assembly building at Site 42 to the launch pad at Site 45. A Zenit rocket carrying the Elektro-L No. 1 satellite lifted off from Baikonur Cosmodrome's Site 45 on January 20, 2011, at 15:29:01 Moscow Time. According to the launch broadcast, around 10 minutes after liftoff, the Fregat-SB upper stage and its payload successfully reached their initial parking orbit. The Russian space agency, Roskosmos, confirmed that the spacecraft had entered orbit. After the first planned firing of the engine onboard the Fregat upper stage, Western radar found the vehicle in the predicted orbit. Fregat's second firing was also reported to be successful. A half an hour after midnight Moscow Time on January 21, 2011, Roskosmos confirmed that the Fregat upper stage had released the satellite as planned. The same night, Deputy Head of Roskosmos Anatoly Shilov said that Elektro-L had successfully deployed its solar panel and the first series of tests showed flawless operation of all systems onboard the satellite. For its ride to orbit on Jan. 20, 2011, 15:29 Moscow Time, Elektro-L used a brand-new combination of the Zenit rocket and the Fregat-SB upper stage. In turn, it was the inaugural launch of the Fregat-SB version of the upper stage, featuring an additional jettisonable external tank, or SBB. The same launch vehicle configuration would be used for a number of future Russian launches. Some 8.6 minutes after launch, at an altitude of 205 kilometers the Fregat-SB upper stage with its payload was expected to separate from the second stage of the Zenit rocket entering an initial 178 by 640-kilometer parking orbit. A total of three burns of the Fregat-SB upper stage were planned before delivery of the satellite into its operational orbit. The first burn would use propellant exclusively from the external tank, which would be jettisoned immediately after engine shutdown. This maneuver would leave the stack in a 306 by 4,440-kilometer orbit with a 50.4 degree inclination. Fregat would then fire again entering a 361 by 35,914-kilometers orbit. Finally, the third burn would "circularize" the orbit and reduce its inclination to only 0.5 degrees, after which Fregat would separate and move away into a safe "burial" orbit. Like its predecessor in the 1990s, Elektro-L was to be "stationed" over the Indian Ocean at 76 degrees East longitude, where it was expected to function for 10 years. Following its separation from the Fregat-SB upper stage, the Elektro-L satellite was initially inserted into a quasi-geostationary orbit at 54 degrees East longitude. It meant that the satellite's orbital altitude was slightly different from that of a regular geostationary orbit, causing the spacecraft to "drift" relative to a single point over the Equator, thus carrying it toward its final destination. Immediately after the launch, the Klen–E ground control station in Medvezhi Ozera near Moscow, responsible for sending commands to the satellite and receiving its telemetry, faced problems with accurate tracking of the spacecraft. The initial attempt to precisely lock the antennas in Medvezhi Ozera onto Elektro-L according to pre-launch calculations had failed. In order to accurately predict the satellite's movement, the optical tracking station in Terskol in Southern Russia and the Ritm radar facility in Medvezhi Ozera had to be employed. As it turned out, Elektro-L was drifting eastward at a rate of about three degrees per day, which was faster than expected, thus preventing its tracking based on original predictions. In addition, engineers at Lavochkin's control station in Khimki experienced radio–interference apparently from a nearby source of radio waves, which prevented deciphering telemetry signals from the satellite. In the meantime, the faster movement of the satellite meant that by January 25, 2010, ground control would need to start maneuvering the satellite, in order to slow down its approach toward its final destination a day later. Delaying the maneuver could cause the satellite to pass its destination and require additional propellant consumption later in order to reverse its drift. Elektro-L launch timeline (Moscow Decree Time) on Jan. 20, 2011:
Following the arrival at its operational orbit, Elektro-L was expected to go through a series of tests during two or three weeks. On February 3, 2011, the satellite reached its destination at 76 degrees East longitude over the Equator and ground controllers successfully adjusted its orbit to stop further drift of the satellite, so it would remain in its operational position. In the crowded geostationary orbit, a further drift of Elektro-L would have led it to pass as close as 10 kilometers from the SES-7/Indostar-2 communications satellite "parked" at 108.15 degrees East on February 6, 2011. Several months into the mission, it was revealed that Elektro-L did experience a failure of one of four gyroscopic attitude control channels immediately after the launch. Although, the problem was reportedly compensated with the use of onboard sensors, the launch of the Spektr-R space observatory, which used a similar system, had to be delayed. In mid-July 2011, Roskosmos announced that the testing of systems onboard the Elektro-L satellite had entered its final stage, while the trials of its ground control segment were still ongoing. Specialists were conducting test evaluation of the satellite's imagery and had completed a 10-day cycle of continuous photography. Updates to the algorithms of the image-processing software had been underway based on the produced test imagery, the agency said. On July 25, 2011, Russia's official RIA Novosti news agency quoted the head of the Elektro-L project at NPO Lavochkin, Vladimir Babyshkin, as saying that the flight testing of the spacecraft had been completed and the State Commission overseeing the launch was expected to declare Elektro-L operational soon. At the time, NPO Lavochkin was manufacturing the second Elektro-L satellite with a projected launch date in 2013. (496) Elektro-L moves to a new position On July 13, 2016, several months after the launch of the second Elektro-L satellite, the original Elektro-L No. 1 spacecraft began maneuvering from its long-time position over the Indian Ocean at 76 degrees East longitude to a new orbital location in the geostationary orbit over the Atlantic at 14.5 degrees West longitude. According to the mission control in Korolev, the satellite was commanded to initiate an engine firing at 13:18 Moscow Time (6:18 a.m. EDT) lasting 387.9 seconds. It raised the satellite's orbit by 289 kilometers and caused it to begin a westerly drift with a rate of around 2.03 degrees per day. The satellite was expected to spend around 45 days drifting toward its new destination, mission control said at the time. Additional maneuvers on August 24 and August 30 slowed the drift of the spacecraft to 0.74 and 0.09 degrees per day, respectively. Finally, another maneuver on September 7, 2016, brought the satellite very close to the geostationary orbit with a tiny drift of 0.012 degrees per day. On October 3, 2016, the mission control in Korolev announced that the spacecraft had come to a vicinity of its orbital position of 14.5 degrees West longitude over the Equator and the transfer had been completed. According to industry sources, Elektro-L1 stopped operating in October 2016 and was officially declared withdrawn from service in 2017.
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