Sunday, December 18, 2016

Arianespace to Launch Two Communications Satellites for Brazil and Japan

Star One D1 and JCSAT-15 satellite being encapsulated in the payload fairing. Photo Credit: Arianespace.

Arianespace is gearing up for its last orbital mission of the year that will see two communications satellites lifting off atop an Ariane 5 booster. The rocket, carrying Brazil’s Star One D1 and JCSAT-15 for Japan, will blast off on Wednesday, Dec. 21, from the ELA-3 launch complex at the Guiana Space Center in Kourou, French Guiana. Liftoff is planned during a one-hour, 15-minute launch window starting at 5:30 p.m. local time (20:30 GMT; 3:30 p.m. EST).

Wednesday’s mission, designated VA234 in Arianespace’s numbering system, is tasked with delivering the duo of commsats into a geosynchronous orbit 155 x 22,307 miles (250 x 35,900 kilometers), inclined six degrees. Star One D1 will be released first, some 29 minutes into the flight, while JCSAT-15 will separate 14 minutes later.

Launch campaign started with the arrival of the JCSAT-15 satellite in Kourou on Oct. 28. Then, the spacecraft was transferred by road for processing inside the Guiana Space Center’s S5 satellite preparation facility.

On Nov. 2, the campaign start review was conducted and Ariane 5’s cryogenic main stage (EPC) was unpacked and erected at the Launcher Integration Building (BIL). Next the launcher’s solid rocket boosters (EAPs) were delivered to this facility and integrated with the EPC on Nov. 4.

Fitchecks of the JCSAT-15 satellite started on Nov. 10 and four days later the Star One D1 spacecraft arrived in French Guiana. On Nov. 15, the engineers conducted fitchecks of the Brazilian satellite and both passengers of the VA234 flight were then ready for last checkouts and tests before their integration with the launch vehicle.

EPC with solid boosters attached was transferred to the Final Assembly Building (BAF) on Nov. 30 and awaited for the satellites which were delivered in mid-December to this facility. JCSAT-15 and Star One D1 were encapsulated in the payload fairing and integrated with the launcher between Dec. 11 and Dec. 15.

Final checks of the payload were carried out on Dec. 16 and launch rehearsal was conducted one day later. The launch readiness will be completed on Dec. 19, clearing the rocket for its rollout that will take place one day before the planned liftoff.

The final countdown for the launch is scheduled to start about 11 hours and 43 minutes ahead of blastoff. During the first two hours of the countdown campaign, the engineers will have an opportunity to perform the last checks of electrical systems. Next, approximately four hours and 23 minutes before liftoff the propellant loading operations will begin as the teams will start to fill the launch vehicle with liquid oxygen and hydrogen.

Last checks of connections between launcher and the telemetry, tracking and command systems are planned to be commenced about one hour and 15 minutes ahead of liftoff. Start of the synchronized sequence is slated to begin seven minutes before the launch. During this last crucial phase of the countdown, the launch vehicle will be switched to the onboard power mode and the onboard systems will take control over the mission. All these operation will lead to the ignition of the rocket’s main stage at T-0 and ignition of the solid rocket boosters seven seconds later, sending the launcher skyward.

Built by Space Systems Loral (SSL), Star One D1 a multi-mission communications satellite based on SSL’s 1300 platform. It has a mass of 6.4 metric tons and its dimensions are: 16.7 x 7.2 x 7.7 feet (5.1 x 2.2 x 2.35 meters). The satellite features two deployable solar arrays generating up to 17.1 kW of power. It is expected to be operational for more than 15 years.

Star One D1 will be operated by Embratel Star One - a Brazilian communication satellite company. The spacecraft is equipped in 70 transponders in Ka-, C- and Ku-band and will serve multiple missions, including telecommunications, television broadcast, broadband, cellular backhaul, and other services such as digital inclusion in Brazil and in the Latin American region. 

“It has a configuration of 28 x 36 MHz transponders (signal receptors and transmitters) in C Band, 24 x 36 Mhz in Ku Band and 18 in Ka Band (equivalent to 300 x 36 MHz, approximately),” according to the Embratel Star One’s website. 

To deliver its services, the satellite will be located at 84 degrees West longitude. This position will allow it to extend the operation of the company’s Brasilsat B4 satellite on C Band, besides bringing new capacities in Ku (covering Latin America) and Ka (covering Brazil) bands.

JCSAT-15 was also built by SSL and is based on the 1300 bus. It weighs about 3.4 metric tons and has dimensions of: 17 x 10.8 x 9.8 feet (5.2 x 3.3 x 3 meters). The satellite is fitted with two power-generating solar panels, providing 10 kW of power. Its designed lifetime is more than 15 years.

JCSAT-15 will be operated by SKY Perfect JSAT Corporation - a Japanese satellite communication and multi-channel pay TV company. Equipped in Ku-band transponders, the spacecraft will be used to help broadcast the multichannel pay TV service in Japan, and will also provide data transfer communications and maritime and aviation applications for the Oceania and Indian Ocean Region.

“JCSAT-15 will allow SKY Perfect JSAT to contribute to the new era of TV broadcasting by offering Ultra HD or 4K programming. In addition, its expanded coverage will help us to fulfill the growing demand for mobile connections,” said Shinji Takada, Representative Director, president and CEO of SKY Perfect JSAT.

The new satellite will replace the company’s N-SAT-110 spacecraft, currently located at 110 degrees East longitude.

The Ariane 5 in ECA configuration that will be employed for Wednesday’s launch is the heavy-lift rocket Arianespace uses for missions to geostationary transfer orbit (GTO) and usually carries two telecommunications satellite payloads.

The flight is powered during the initial flight phase by a cryogenic core stage and two solid rocket boosters, followed by the use of a cryogenic upper stage for orbital injection of the payload.

The 180-foot (54.8-meter) tall ECA is an improved version of the Ariane 5 launcher, designed to deliver payloads, mainly communications satellites, weighing up to 10 metric tons.

Although it has the same general architecture, some significant changes were made to the basic structure of the generic version to increase thrust and enable it to carry heavier payloads. ECA is also used by institutional customers for non-GTO missions; for example, launching ESA’s Herschel and Planck scientific missions in 2008.

Wednesday’s mission will be Arianespace’s 11th launch of the year, and the seventh Ariane 5 flight from Kourou in 2016. The satellites will be 60th and 61st SSL spacecraft launched by Arianespace to date.

Arianespace’s next launch is scheduled for Jan. 28 when it is expected to send into orbit Hispasat AG1 communications satellite for the Spanish company Hispasat. The mission will be performed by the Soyuz ST-B launcher, lifting off from Kourou.

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