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GLONASS


GLONASS-K

Above: GLONASS-K satellite. Copyright © 2009 Anatoly Zak


As its American counterpart, the Russian satellite navigation system, known as GLONASS, was designed to determine the coordinates and the speed of an aircraft, a vessel or any other vehicle across the globe. The third-generation satellite in the Russian global positioning system was known as GLONASS-K.

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Russia orbits a new-generation GPS bird

Published: 2011 Feb. 25; updated Feb. 26

A lighter, better version of the Russian navigation satellite went into orbit for a real-time test. The new spacecraft, designated GLONASS-K, promises to eventually replace the GLONASS-M satellites which currently comprise Russia's space-based global positioning system.

A Soyuz-2.1b rocket with a Fregat upper stage carrying the GLONASS-K1 (No. 11) satellite lifted off on Feb. 26, 2011, at 06:07:15 Moscow Decree Time, from Pad 4 at Site 43 the Plesetsk launch site. This was the first time a satellite for the GLONASS constellation flew onboard the Soyuz-2 rocket from Russia's northern launch site. All previous missions in the program originated from the Baikonur cosmodrome in Kazakhstan and were carried by Proton rockets.

The switch from launching trios of satellites on Proton to delivering single spacecraft on smaller Soyuz rockets marks the transition from building the GLONASS constellation to its replenishment and maintenance. Still, according to the manufacturer, the GLONASS-K satellite was designed to be fully compatible with both Soyuz and Proton rockets. It was originally reported that Soyuz-2 rockets could carry a pair of GLONASS-K satellites during operational missions.

According to the planned flight profile of the GLONASS-K1 mission, a three-stage Soyuz-2 rocket was to release Fregat and its payload on a suborbital trajectory. The Fregat upper stage would then fire its own engine for 19 seconds to enter an initial 212 by 241-kilometer parking orbit with an inclination of 64.8 degrees toward the Equator. Fregat would then fire its engine for 564 seconds to enter an elliptical 278 by 19,145-kilometer orbit. Upon reaching the apogee (the highest point) of this orbit, Fregat's engine would make a third 224-second maneuver to enter its final nearly circular orbit with an altitude of about 19,140 kilometers. The inclination toward the Equator would remain the same throughout the mission.

Soon after the launch, the Russian space forces confirmed that facilities of the Titov chief test and control center had started tracking the mission at 06:10 Moscow Time. The Russian space agency then announced that Fregat had separated from the third stage of the launch vehicle at 06:16 Moscow Time and the payload entered the initial parking orbit. Ground control was expected to establish contact with the satellite at 09:44 Moscow Time on the same day. The Ministry of Defense then did confirm that following the separation of GLONASS-K from the upper stage at 09:41:03 Moscow Time, ground facilities had established control over the satellite at 09:44 Moscow Time.

A recap of the GLONASS-K launch on Feb. 26, 2011 (Moscow Decree Time):

  • 06:07:15 - Liftoff
  • 06:10 - Russian ground facilities start tracking the mission
  • 06:16 - Fregat upper stage with its payload separates from the third stage of the Soyuz-2 launch vehicle
  • 09:41:03 - GLONASS-K separates from the Fregat upper stage
  • 09:44 - Ground stations establish control over the satellite

Officially designated Kosmos-2471, the first GLONASS-K satellite lowered its orbit to an operational altitude one month after launch.

GLONASS-K satellite

The GLONASS-K version was based on the brand-new Ekspress-1000K platform developed by NPO PM design bureau (later renamed ISS Reshetnev). The spacecraft featured a lighter, standardized unpressurized bus. The version also featured a third L-band transmitter for civilian users. The 935-kilogram GLONASS-K spacecraft was designed for a no-less than 10-year life span, considerably longer than its predecessors. Thanks to its extended service life, the satellite promised to cut its cost in half. The satellite's payload would also deliver more precise navigation than its predecessors and provide search and rescue functions. In December 2006, the head of NPO PM, Nikolai Tostoedov, promised the first launch of the GLONASS-K spacecraft for 2009, a year later than the launch date projected in 2005. At the time, GLONASS-K were expected to be launched by the Soyuz-2 rocket from Plesetsk, instead of Proton. However in 2009, official Russian documents said that the production of GLONASS-K satellites had only started that year. (367) The first launch was then expected in 2010. In a 2010 interview the head of Roskosmos quoted 2011, for the first launch of the GLONASS-K spacecraft, however in September 2010, the first GLONASS-K launch was promised for the end of December of that year.

By 2012, it was also decided to equip GLONASS-K satellites with KOSPAS-SARSAT search and rescue signal hardware, which was previously carried on the ill-fated Sterkh satellites and whose further development had been canceled.

Preparations for launch

In December 2010, the launch of GLONASS-K was postponed from Dec. 28, 2010 and during January 2011 it slipped from Feb. 15 to Feb. 24, 2011. The satellite was finally returned to the launch site on Feb. 11, 2011.

As the first launch attempt was being prepared on the morning of Feb. 24, 2011, 57 minutes before a liftoff scheduled for 06:11:19 Moscow Time, an automated system interrupted the pre-launch sequence, apparently due to problems with the flight control system onboard the Soyuz-2.1b rocket. According to initial reports, a new launch attempt would be made exactly 24 hours later after replacement of the avionics box in the flight control system, however a longer delay was also apparently discussed. Indeed by the end of the day on February 24, Lt. General Oleg Ostapenko, a commander of the Russian space forces, told Russian media that due to the extra time required to re-check failed systems, the next launch attempt would take place on the reserve date of Feb. 26, 2011. The meeting of the State Commission to review the readiness for the launch was expected around noon February 25, Ostapenko said.

GLONASS-K2

A modified version of the GLONASS-K spacecraft, known as GLONASS-K2, would introduce a new type of navigation signal with so-called code-protected selection. The spacecraft would transmit three types of signals, two of which in L1 and L2 range would be designed for special users, (such as armed forces) and one in L1 range would be available to everyone else. As of 2010, the launch of the first GLONASS-K2 spacecraft was expected in 2013. (438) In November 2012, ISS Reshetnev announced the completion of the preliminary design for a modified GLONASS-K satellite was scheduled for October 2013.


APPENDIX

A summary of the Fregat upper stage maneuvers during the launch of the GLONASS-K1 satellite:

Maneuver
Burn duration
Resulting orbit
Inclination
Apogee
Perigee
Period
1st burn
19 seconds
Initial/parking
64.8 degrees
212 kilometers
241 kilometers
88.8 minutes
2nd burn
564 seconds
Transfer
64.8 degrees
278 kilometers
19,145 kilometers
336.5 minutes
3rd burn
224 seconds
Operational
64.8 degrees
19,132 kilometers
19,149 kilometers
675.7 minutes

 

Known specifications of the GLONASS-K satellite:

  GLONASS-K
Mass
745 kg (935 kg)**
Payload mass
260 kilograms
Onboard power supply
1,270 Watts
Payload power consumption
750 Watts
Attitude control accuracy
0.5 degrees
Solar panel orientation accuracy
1 degree
Operational life span
10 years*
First launch
2007 (originally); 2009 (as of end of 2006) 2010 (as of end of 2009)

*As of 2009. Previously, Uragan-K's design life was quoted as 12-15 years;

**Original target mass of 745 kilograms proved to be unachievable by the beginning of flight testing in 2011.


This page is maintained by Anatoly Zak; last update: November 16, 2012

Page editor: Alain Chabot; Last edit: March 7, 2011

IMAGE ARCHIVE

GLONASS-K

The Uragan-K model originally promised to extend life span of individual satellites within GLONASS constellation to 12 or even 15 years. Later specifications called for a 10-year "guaranteed service life." Click to enlarge. Copyright © 2005 Anatoly Zak


GLONASS-K transport

A GLONASS-K satellite is being prepared for transportation. Credit: ISS Reshetnev


Soyuz

The Soyuz-2.1b rocket with the first GLONASS-K satellite on the launch pad in Plesetsk in February 2011. Credit: Roskosmos


Launch

GLONASS-K1 lifts off on Feb. 26, 2011. Credit: Rossiya 24 via Claude Mourier