Luch satellite

Related page:

Searching for details:

The author of this page will appreciate comments, corrections and imagery related to the subject. Please contact Anatoly Zak.

Previous chapter: Luch series

Russian space-based mission control to be reborn

Published: 2011 Dec. 10

A new-generation satellite entered orbit to give back Russian mission controllers the capability of the beyond-horizon contact with critical space missions for the first time in more than a decade.

The Luch-5A spacecraft, designed to transmit data from the Russian segment of the International Space Station, ISS, as well as from unmanned missions, likely including secret military satellites, lifted off from Pad 24 at Site 81 of Baikonur Cosmodrome, Kazakhstan, as scheduled at 15:17 Moscow Time, on Sunday (6:17 a.m. EST). Several minutes after the launch, GKNPTs Khrunichev, which builds the mission's launch vehicle, confirmed that the payload section had reached its initial parking orbit. Following the third successful firing of Briz-M, the upper stage dropped its external propellant tank some 3.8 hours after the liftoff.

Positioned in the geostationary orbit 36,000 kilometers away from Earth, Luch-5A will relay live telemetry and other information from low-orbiting Russian space vehicles as they fly beyond the communication range of ground control stations. Several sources quoted an altitude of 2,000 kilometers as a ceiling for the spacecraft capable of taking advantage of Luch, however, this info probably originates from a legal definition of "low orbits." More likely, spacecraft could communicate via Luch-2 from much higher altitudes. In addition to spacecraft, launch vehicles and upper stages could reportedly use Luch to relay real-time data to ground stations during active phases of delivering payloads into orbits.

In order to maintain communications, antennas onboard Luch were designed to home on fast-moving targets and follow them along their trajectories. The satellite is equipped with a pair of large high-gain antennas, one of which is working in Ku-band and another in S-band. Each antenna can independently track its target. Thanks to the capability of two-way communications via Luch, ground stations could send commands to spacecraft, which otherwise would be beyond their reach.

In addition, Luch-5A is capable of receiving emergency signals from the KOSPAS-SARSAT system and transmitting them to ground stations. Finally, the satellite was designed to help in correcting measurements from GLONASS navigation satellites, thus improving accuracy of the constellation.

A previous Russian data-relay satellite from the Luch (beam) series flew in 1995 and ceased operations in 1998. Since then, Russia had to turn to services of the US Tracking and Data Relay Satellites, TDRS, for monitoring of crucial operations onboard the ISS, including spacewalks outside the station. Although the high-gain antenna on the service module of the ISS was designed for communications via Luch, additional hardware would have to be installed on the exterior and inside the Russian segment to take advantage of the system by the time Luch-5A flew.

Ironically, the Luch-5A mission is overshadowed by an international effort to re-establish communications with a stranded Phobos-Grunt spacecraft, which had been hampered by the lack of monitoring assets. (The Mars-bound Phobos-Grunt was not equipped to maintain contact via Luch satellites.)

Path to orbit

The Luch-5A spacecraft, developed by ISS Reshetnev of Zheleznogorsk, shared its ride into orbit onboard the Proton-M/Briz-M rocket with the Amos-5 communications satellite, which was built by the same Russian company for an Israeli satellite operator.

The payload section, including the Briz-M upper stage and two of its passengers with a total mass of 3,137 kilograms, first entered a 172.8 by 173-kilometer orbit with an inclination 51 degrees toward the Equator. The upper stage then boosted its payload to a 262.4 by 4,997.7-kilometer orbit and reduced an inclination to 50.4 degrees. Another maneuver moved the pair to a 395.7 by 35,982-kilometer orbit, while further reducing an inclination to 47 degrees.

Both satellites were to be released in a circular orbit with an altitude of around 36,000 kilometers, however, Luch-5A would have an inclination 5 degrees toward the Equator, while Amos-5 would be left in a final geostationary orbit with an inclination 0 degrees. Following the release of Amos-5, Briz-M would maneuver itself away from its payload.

In the early hours of December 12, sources Spacecom, the Amos-5 operator based in Tel-Aviv, Israel, reported that the spacecraft successfully deployed its communications antennas and solar panels and was functioning well. In turn, ISS Reshetnev announced that Luch-5A had been functioning well and both satellites had been performing initial attitude control.

Luch-5A and AMOS-5 launch timeline on Dec. 11, 2011:

Event	Mission elapsed time	Moscow Time	GMT	EST
Liftoff	00:00:00	15:17:00	11:17:00	6:17 a.m.
Separation between Stage I and II	00:02:06	15:19:06	11:19:06	6:19 a.m.
Separation between Stage II and III	00:05:34	15:22:34	11:22:34	6:22 a.m.
Payload fairing separation	00:05:44	15:22:44	11:22:44	6:22 a.m.
Separation between Sate III and payload section	00:09:41	15:26:41	11:26:41	6:26 a.m.
Start of the 1st firing of the Briz upper stage	00:11:15	15:28:15	11:28:15	6:28 a.m.
End of the 1st firing of the Briz upper stage	00:15:38	15:32:38	11:32:38	6:32 a.m.
Start of the 2nd firing of the Briz upper stage	01:07:35	16:24:35	12:24:35	7:24 a.m.
End of the 2nd firing of the Briz upper stage	01:25:21	16:42:21	12:42:21	7:42 a.m.
Start of the 3rd firing of the Briz upper stage	03:28:25	18:45:55	14:45:55	9:45 a.m.
End of the 3rd firing of the Briz upper stage	03:46:53	19:03:53	15:03:53	10:03 a.m.
Separation of the external tank of the Briz upper stage	-	19:05:14	15:05:14	10:05 a.m.
Start of the 4th firing of the Briz upper stage	08:40:26	23:57:26	19:57:26	2:57 p.m.
End of the 4th firing of the Briz upper stage	08:53:00	00:10:00*	20:10:00	3:10 p.m.
Separation of the Luch-5A satellite from the Briz upper stage	08:54:10	00:11:10*	20:11:10	3:11 p.m.
Start of the 5th firing of the Briz upper stage	09:33:08	00:50:08*	20:50:08	3:50 p.m.
End of the 5th firing of the Briz upper stage	09:33:55	00:50:55*	20:50:55	3:50 p.m.
Separation of the AMOS-5 satellite from the Briz upper stage	09:35:05	00:52:05*	20:52:05	3:52 p.m.
Briz-M initiates maneuvers to go away from its payload	-	03:12:05*	23:12:05	6:52 p.m.
Briz-M completes maneuvers to go away from its payload	-	04:24:30*	00:24:30*	7:52 p.m.

*December 12

Luch-5 and 4 projects (Luch-M)

In 2005, with the improvement of economic situation, Russian space agency, Roskosmos, awarded NPO PM (later ISS Reshetnev) based in Zheleznogorsk, a new contract to develop a lighter cheaper version of relay satellites designated Luch-5A and Luch-5B. These satellites were designed for a 10-year lifespan instead of three years for Luch-1 and 2. According to the original plan, both satellites would be based on the standard Ekspress-1000 platform and could be carried into the geostationary orbit orbit by the Soyuz-2/Fregat launcher. In June, their scale models appeared at NPO PM's exhibit at the Paris Air and Space Show in Le Bourget, France.

With the removal of post-Cold War barriers, ISS Reshetnev outsourced the production of low-noise amplifiers and transmitters for the satellite to Japanese firm Sumitomo. A European Thales Alenia Space was sub-contracted to build power amplifiers and other components for an onboard repeater for Luch-5A and 5B.

Luch 4 satellite

By 2008, following the decision to build a new Russian space port in Vostochny, plans were hatched to add a third, more capable satellite -- Luch-4 -- into the Russian data relay constellation. The latest satellite would have a primary task of "covering" missions from the Far Eastern site, which would head into orbit over the Pacific Ocean, mostly out of view by Russian ground stations.

Unlike its one-ton predecessors, Luch-4 would have a mass of three tons and would need a Proton-M/Briz-M launch vehicle to enter orbit.

In February 2009, ISS Reshetnev reached a contract with the Russian space agency, Roskosmos, for the development of the Luch-4 satellite designed to function for 12 years. it was expected to enter orbit, while Luch-5A and 5B would still operate in orbit. With Luch-4, developers promised to expand the capabilities of the system to match the US latest Advanced TDRSS network.

Luch-4 would have a capability for satellite-to-satellite communications in KA-band and carry an experimental transponder for a mobile personal communications system.

At the time, it was expected to deploy the Luch constellation according to the following schedule:

Luch-5A to be launched in December 2010 to a position 16 degrees West longitude over the Atlantic;
Luch-5B to be launched in December 2011 to a position 95 degrees East longitude over the Indian Ocean;
Luch-4 - to be launched in December 2013 to a position 167 degrees East longitude over the Pacific Ocean; (455)

However by the time, Luch-5A was launched in 2011, plans surfaced to replace the Luch-4 spacecraft with the third copy of the Luch-5 spacecraft. Designated Luch-5V, it would fly in tandem with KazSat-3 satellite.

Path to launch pad

Originally, the launch of the first Luch-5 satellite was expected in the second quarter of 2009, however it had to be delayed to 2010 and 2011. In the wake of the Proton rocket failure in December 2010, the Luch-5A mission, then officially scheduled to fly in June 2011, had to trade places with the launch of the 44th trio of GLONASS satellites, which were previously expected to fly in September 2011. At the time, the Luch mission was expected in September 2011. By the end of May 2011, Roskosmos promised the launch in the first half of Fall 2011. The mission was then likely to slip to 2012, but later moved forward to December 2011.

Luch-5 satellite

The 950-kilogram Luch spacecraft and Amos-5 are based on the Ekspress-1000N platform and designed for a 10-year life span. Luch-5 is expected to be stationed at 16 degrees West longitude, where it would deploy two independently targeted S- and Ku-band antennas to enable communications between spacecraft in the low Earth orbit, including ISS, with mission control, as they fly beyond the range of Russian ground control network. Luch-5A was previously expected to fly onboard Soyuz-2-1b/Fregat.

APPENDIX

Known specifications of the Luch-5A satellite:

-	As of 2005	As of 2010
Total launch mass	950 kilograms	1,150 kilograms
Power supply	1,500 Watts	2,200 Watts*
Earth pointing accuracy	0.1 degrees	0.2 degrees
Station keeping accuracy	0.2 degrees	0.2 degrees
Operational lifespan	10 years	10 years
Dimensions (in deployed position)	8.5 by 11.0 by 16.0 meters	8.5 by 11.0 by 16.0 meters
Number of transponders	7	7
Antenna patterns	Spot beam, steerable and global	Spot beam, steerable and global
Repeater frequency bands	Ku, S, L, P	Ku, S, L, P
Manufacturer	ISS Reshetnev of Zheleznogorsk	ISS Reshetnev of Zheleznogorsk
Launch vehicle	Soyuz-2/Fregat	Proton-M/Briz-M

*at the end of the project lifespan

Page author: Anatoly Zak; Last update: January 22, 2012

IMAGE ARCHIVE

Amos-5 during pre-launch processing in Baikonur in November 2011. Credit: Roskosmos

Luch-5A (right), Amos-5 and Briz-M during final assembly in Baikonur on Nov. 28, 2011. Credit: Roskosmos

A Proton rocket with Luch-5A and Amos-5 satellites shortly after rollout to a launch pad on Dec. 8, 2011. Credit: Roskosmos

A Proton rocket with Luch-5A and Amos-5 satellites lifts off during a rare daylight launch on Dec. 11, 2011. Credit: TsENKI