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Above: Launch scenario of a typical Globalstar-2 mission. Credit: Arianespace
Globalstar-2 satellites The new Globalstar spacecraft has a design life of 15 years or twice the design life of the first-generation Globalstar satellite. To help ensure the reliability of the design life, the second–generation robust architecture has placed particular emphasis on redundancy management and the radiation environment of the Globalstar operational orbit. In addition, each functional chain of the spacecraft was carefully analyzed for implementation of redundancies and tolerances to minimize single point failures. Each second-generation Globalstar satellite weighs approximately 700 kilograms, offers power of 2.4 kW, is fitted with 16 transponders from C-to S-band, and 16 receivers from L- to C-band. The satellite's trapezoidal body is fabricated from rigid aluminum honeycomb panels. The trapezoidal shape was selected to conserve volume and to allow the mounting of multiple satellites under the launch vehicle's payload fairing. The satellites were designed to operate in the 920-kilometer orbit with the inclination 52 degrees toward the Equator. The satellite operates in a body-stabilized, three-axis attitude control mode and uses sun sensors, Earth sensors, and a magnetic sensor to help maintain attitude. The satellite utilizes thrusters for orbit-raising, station-keeping maneuvers and attitude control. The spacecraft's thrusters are fueled from a single on-board propellant tank. The two solar arrays provide the primary source of power for the Globalstar spacecraft, while batteries are used during eclipses and peak traffic periods. The solar panels automatically track the Sun as the satellite orbits the Earth, providing maximum possible exposure to the solar energy. The heart of a Globalstar satellite is its communications systems. These systems are mounted on the Earth deck, which is the larger of the two rectangular faces on the satellite's body. There are C-band antennas for communications with Globalstar gateways, and L- and S-band antennas for communications with user terminals. Designed with the same frequencies and beam patterns which are compatible with existing gateway antenna and ground infrastructure, each second-generation satellite can be mixed seamlessly with Globalstar’s first-generation satellite operations. The second-generation satellites are designed to support Globalstar’s current lineup of voice, Duplex and Simplex data products and services including the Company’s lineup of SPOT retail consumer products. Once the Company’s next-generation ground network is installed, the advanced constellation will also provide Globalstar customers with enhanced future services featuring increased data speeds of up to 256 kbps in a flexible Internet protocol multimedia subsystem, IMS, configuration. Products and services supported are expected to include: push-to-talk and multicasting, advanced messaging capabilities such as multimedia messaging or MMS, geo-location services, multi-band and multi-mode handsets, and data devices with GPS integration. Launch contract Globalstar was the very first customer for Starsem, which was created to perform commercial Soyuz missions from Baikonur. Using six Soyuz launchers from February and November 1999, it orbited 24 450-kilogram first-generation satellites for Globalstar - representing one-half of the company's original constellation. From May 2007 to October 2010, two follow-on Soyuz missions lofted eight additional satellites to join the Globalstar constellation. Four launches of six Globalstar-2 satellites each were also contracted to Arianespace using the Soyuz-2 launch vehicle. For Globalstar-2 missions, Soyuz-2 was equipped with a 6.7-meter-high conical-shaped dispenser, on which the six satellites were installed. Satellites were installed on a purpose-built dispenser system that carried two spacecraft mounted on its upper section and four on the lower portion. The original "service and solutions" contract for the first Globalstar-2 mission was announced by Arianespace on Sept. 4, 2007. According to the plan, the Soyuz-2 rocket would launch first of four missions from a brand-new launch complex in Kourou, on Dec. 28, 2009. At the time, four additional launches were expected, thus delivering all 48 satellites of the Globalstar-2 constellation. As of November 2008, due to delays in the construction of the Soyuz launch pad in French Guiana, at least one cluster of Globalstar-2 satellites was expected to be moved to Baikonur, still maintaining the launch date in 2009. The first launch was delayed from the summer of 2009. As of July 2009, the mission was expected in May 2010. As of Jan. 10, 2010, the launch date was identified as an "opening of a 90-day launch window on July 5, 2010." The Soyuz 2-1a launch vehicle carrying the initial cluster of six Globalstar second-generation satellites lifted off from Baikonur Cosmodrome's Pad 6 at Site 31 in Kazakhstan on October 19, 2010, at 21:10:59 Moscow Time. The mission was conducted by Starsem, an affiliate of Arianespace company. An eight-minute 49-second powered flight of three booster stages was followed by two engine firings of the Fregat upper stage with 50 minutes of free flight in between. The satellites were then separated from the upper stage in two batches, the first two (Globalsatar-2 No. 5 and 6) - one hour 38 minutes after the liftoff and the second batch of four satellites (Globalstar-2 No. 1, 2, 3 and 4) - two minutes later. The mission delivered six 700-kilogram spacecraft into a circular phasing orbit, utilizing the version of the Soyuz rocket that was then scheduled to be introduced by Arianespace at the yet-to-be-completed launch pad in Kourou, French Guiana in 2011. The mission was the first of four Soyuz launches booked with Arianespace to deploy a total of 24 second-generation satellites. Once the first six new Globalstar satellites are in operational orbit, the most immediate service improvement will benefit those customers who use the Company’s voice and Duplex data services. With each subsequent launch, these customers can expect a progressive return to the high reliability and service quality enjoyed before 2007. On July 13, 2011, Arianespace successfully orbited a second batch of six spacecraft for Globalstar's second-generation satellite network on a mission performed with the medium-lift Soyuz launcher from Baikonur Cosmodrome in Kazakhstan. The flight was carried out on Arianespace's behalf by its Starsem affiliate, lifting off on July 13, 2011, at 06:27:04 Moscow Summer Time from Site 31. Soyuz' Fregat upper stage then performed two successive firings, followed by the orbital injection of the six satellites one hour and 38 minutes after liftoff. The mission was the 23rd for Starsem and utilized the Soyuz 2 evolved version of Russia's venerable medium-lift workhorse launcher. Incorporating the enlarged ST payload fairing and an updated digital flight control system. This mission was being prepared for takeoff on July 11, 2011, however due to a malfunction of an equipment on the Soyuz launch pad during the last seconds of the launch sequence, the launch has been postponed for 24 hours. The launch vehicle and the six satellites have been placed in stand-by mode and maintained in fully safe conditions. A new launch attempt was re-scheduled for July 12 at 08:43 a.m. Baikonur time (02:43 a.m. UTC). However, on that day, the launch was scrubbed again, in order to complete the Soyuz launch system’s reconfiguration to a launch-ready mode, Arianespace said. The mission was then slated for liftoff on July 13 at 8:27 a.m. local time at Baikonur Cosmodrome (2:27 a.m. UTC). Third Globalstar-2 mission Closing one of the most difficult years in the history of the Russian space industry, the nation's workhorse rocket successfully completed a make-or-break mission following two failures involving the Soyuz family of launch vehicles in 2011. A Soyuz-2-1a rocket lifted off on Wednesday, Dec. 28, 2011, at 21:09 Moscow Time (17:09 GMT) from the Baikonur Cosmodrome's Pad 6 at Site 31. The launch vehicle delivered six Globalstar second-generation communications satellites in a commercial mission managed by Europe's Arianespace company. Preparations for the mission This launch was previously expected on Oct. 8, 2011, however in the wake of the Progress M-12M crash, the third stage of the Soyuz rocket for the mission had to be shipped back to the manufacturer plant in the city of Samara for additional checks. In this mission, the Soyuz-2-1a rocket used the RD-0110 engine on its third stage, analogous to the one which doomed the Progress mission. As of October 13, 2011, the delivery of the Block I upper stage for the mission was scheduled for Nov. 20 and the launch was delayed from beginning of December to Dec. 28, 2011
Soyuz launches fourth Globalstar-2 cluster More than two years after starting the deployment of the Globalstar-2 satellite constellation, a Russian Soyuz-2 rocket lifted off on its fourth mission to deliver a six-satellite cluster. The liftoff of the Soyuz-2-1a/Fregat rocket took place as scheduled on Feb. 6, 2013, at 20:04:24 Moscow Time (16:04 GMT, 11:04 a.m. EST) from Pad 6 at Site 31 in Baikonur. The vehicle was carrying six 700-kilogram Globalstar-2 satellites (Flight Models No. 19-24) completing the 24-satellite mobile-phone communications constellation. The separation of the first pair of satellites from the Fregat upper stage was scheduled for 21:43 Moscow Time (12:43 EST), followed by four remaining spacecraft a minute later. Around 21:50 Moscow Time (12:50 EST), Roskosmos confirmed that the payloads had been released marking the success of the mission. The previous launch attempt was planned for Feb. 5, 2013, at 20:20:22 Moscow Time, however around 18:00 Roskosmos posted a statement announcing a 24-hour delay due to weather. A State commission overseeing preparations for the launch had decided to postpone the liftoff until a backup date of February 6, due to wind loads at altitudes between 8 and 10 kilometers exceeding allowable conditions, Russian space agency, Roskosmos, said. The launch profile The Fregat upper stage was then to fire its own engine, inserting the 8,200-kilogram payload module into a 200-kilometer transfer orbit with an inclination 51.7 degrees toward the Equator. After this first burn, the Fregat performed a barbecue maneuver to maintain proper thermal conditions for the Globalstar-2 spacecraft during the following coast phase, which lasted for about 50 minutes. At the correct point on this orbit, Fregat would fire again, to reach the circular separation orbit. Following stabilization and under visibility of the Russian ground tracking stations, the six satellites were released from the dispenser. The separation of the two satellites of the upper dispenser mast occured first, and 1 minute 40 seconds later, the four satellites of the lower dispenser mast were separated simultaneously 1 hour, 40 minutes after launch. After spacecraft separation, the Fregat upper stage main engine was re-ignited to reenter the stage in the South Pacific ocean. Preparations for the mission Designated ST26 and managed by Arianespace's Starsem venture, the fourth Globalstar-2 launch was previously expected to take place in August-September 2012 and was later postponed until December. First two satellites for the launch arrived to Baikonur on Oct. 17, 2012, a second pair followed on Nov. 14, 2012 and the final two arrived at the beginning of December. By that time, the launch was re-scheduled for February 2013. The satellites were assembled and integrated with the Fregat upper stage and their payload fairing inside the Upper Composite Integration Facility, UCIF, operated by Starsem and located at Site 112 in Baikonur. On January 30, the payload section was transferred to the MIK-40 assembly building at Site 31 for its integration with the Soyuz rocket. The fully assembled launch vehicle was rolled out to the launch pad on Feb. 2, 2013. The first launch attempt was planned for Feb. 5, 2013, at 20:20:22 Moscow Time, however around 18:00 Roskosmos posted a statement announcing a 24-hour delay due to weather. A State commission overseeing preparations for the launch had decided to postpone the liftoff until a backup date of February 6, due to wind loads at altitudes between 8 and 10 kilometers exceeding allowable conditions, Russian space agency, Roskosmos, said.
Globalstar-2 launch history:
Globalstar-2 missions:
This page is maintained by Anatoly Zak Last update: June 21, 2013 |
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The Soyuz-2 rocket with Globalstar-2 satellites shortly before launch on Oct. 19, 2010. Credit: Roskosmos
The Soyuz-2 rocket lifts off on July 13, 2011, with a second batch of six second-generation Globalstar satellites. Note the shape of the payload fairing on this mission. Credit: Arianespace
A cluster of Globalstar-2 satellites being prepared for integration with launch vehicle's Fregat upper stage. Credit: Arianespace
A Soyuz-2-1a rocket with a second pair of Globalstar-2 satellites sits on Pad 6 at Site 31 in Baikonur. Credit: Arianespace
A Soyuz rocket lifts off on Dec. 28, 2011, with Globalstar-2 satellites. Credit: Arianespace
the Soyuz ST payload fairing (at left) being moved into place around the six Globalstar-2 satellites. The spacecraft are installed on a cone-shaped dispenser attached to the Fregat upper stage (right). Credit: Arianespace
Soyuz-2 rocket with fourth batch of Globalstar-2 satellites being rolled out from the assembly building on Feb. 2, 2013. Credit: Roskosmos
Service gantry is retracted around Soyuz-2 rocket some half an hour before launch attempt on Feb. 6, 2013. Credit: TsENKI
Soyuz-2 lifts off on Feb. 6, 2013, with fourth and final six Globalstar-2 satellites in a last commercial mission from Baikonur. Credit: TsENKI |
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