Intelsat 19

Intelsat 19 is a geostationary communications satellite operated by Intelsat. It was constructed by Space Systems Loral,^[1] based on the LS-1300E satellite bus. It was successfully launched by Sea Launch using a Zenit-3SL carrier rocket on 1 June 2012.^[2] Upon entering service it replaced Intelsat 8 at 166° East Longitude.

Telecommunications and Service History

Intelsat 19 carries 24 C-band and 36 K_u-band transponders. The C band payload covers the Asia-Pacific region while the K_u band transponders provide Direct to Home television to Australia. It is expected to operate for fifteen years.

In June 2012, Intelsat 19 successfully transferred to geostationary orbit. All of the satellite’s communications antennas were in their operational positions, and the communications payload was being tested. Data received from the satellite indicated that the south solar array was damaged, and that the power available to the satellite will be reduced. In-orbit testing was expected to be completed by mid-July.^[3]

In July 2012, Intelsat 19 completed its in-orbit testing and the satellite drifted to its final location at 166 East, where it was expected to begin service in mid-August.^[4]

On 13 August 2012, the satellite entered commercial service as customer traffic previously on Intelsat 8 was transitioned over.

Solar array deployment failure and recovery

Intelsat announced late 1 June that its South solar array failed to deploy.^[5][6] The failure followed a pressure/vibration anomaly recorded during launch. The only other time this anomaly was observed on the Sea Launch vehicle was during a 2004 launch which also delivered a payload with solar array damage. Intelsat 19's solar array damage was evident by telemetry – after fairing jettison and before satellite release – during which time the array was exposed to Sun.^[7]

The South solar array panel was eventually deployed on 12 June 2012, following four apogee maneuver firings on 11 June 2012, and appears to have lost 50% of its capacity, leaving the satellite with 75% of its design power capacity. The Ku-band deflector deployment is scheduled for 18 July.^[8][9]

"The preliminary data review indicates that all systems performed nominally throughout the launch profile including fairing and spacecraft separation," said Kirk Pysher, chief operating officer of Energia Logistics Ltd., Sea Launch's technical partner and a subsidiary of Energia Overseas Ltd. of Moscow, the launch provider's majority owner. "Boeing engineers did note an unexpected, isolated event around 72 seconds after launch, which registered on microphones and pressure sensors," Pysher said. "We have only seen this one other time out of the 31 flights and while it is premature to speculate on its origin until further analysis is complete, it bears a striking resemblance to a prior Space Systems/Loral mission."

Peter Stier, a Sea Launch spokesperson, confirmed the prior Space Systems/Loral mission was the Telstar 14/Estrela do Sul 1 launch. During the 2004 mission, sensors registered a similar signature at about the same point in the flight.^[10]

On 19, December 2012 Space Systems/Loral (SS/L) and Sea Launch have confirmed that the Independent Oversight Board (IOB) formed to investigate the solar array deployment anomaly following launch of Intelsat-19 (IS-19) in the spring of 2012 has successfully reached a unanimous conclusion. The IOB concluded: "the anomaly occurred before the spacecraft separated from the launch vehicle during the ascent phase of the launch and originated in one of the satellite’s two solar array wings due to a rare combination of factors in the panel fabrication … After rigorous investigation, the launch vehicle was exonerated from causing or contributing to the anomaly and there were no unexpected interactions between the spacecraft and the launch vehicle." ^[11]

See also

• Gunter's Space Page - Intelsat 19
• Intelsat 20
• Gunter's Space Page - Space Systems Loral: LS-1300
• Space Systems Loral - 1300 Series Satellite Platform

References