Yahsat 1A, Intelsat New Dawn = Ariane 5ECA (VA201) - 22.04.11 21:37 UTC

[us2-star]

Молодцы! 43-й успешный подряд..

[Dude]

Пофиксили и без полугодового разбирательства. Так держать!  

[Salo]

http://www.arianespace.com/news-mission-update/2011/789.asp

Ariane 5 delivers a record performance with two payloads for new Arianespace customers[/size]

April 22, 2011 – Ariane Flight VA201

A heavy-lift Ariane 5 successfully orbited two satellite payloads today that will supply telecommunications services for two new customers who join the growing list of Arianespace commercial launch services users.

In a flight conducted from the Spaceport in French Guiana, the Ariane 5 deployed Yahsat Y1A, the first satellite to be operated by the United Arab Emirates' Al Yah Satellite Communications Company; along with Intelsat New Dawn, which was built for the new joint venture of Intelsat and Convergence Partners.

Adding to this mission's milestones was the lift performance record for Ariane 5: delivering a total mass of 10,050 kg. to geostationary transfer orbit, of which 8,956 kg. was the combined weight of its two satellite payloads.

Lifting off on time at 6:37 p.m. in French Guiana, the Ariane 5 climbed through a partial cloud cover at sunset, and continued its downrange flight in clear skies.  This allowed a direct view of the separation for Ariane 5's two solid propellant boosters at an altitude of 66.5 kilometers, followed by the payload fairing's jettison at a 105-kilometer altitude.

It marked another of Ariane 5's highly accurate flights, with the following estimated orbital parameters at the injection of its cryogenic upper stage:
- Perigee: 249.8 km. for a target of 249.7 km.
- Apogee: 35,975 km. for a target of 35,956 km.
- Inclination:  5.98 deg. for a target of 6.00 deg.

For tonight's mission, Yahsat Y1A was positioned in the upper passenger slot of Ariane 5's dual-payload "stack," and was released at 27 minutes into the flight.  This spacecraft was built by Astrium based on the Eurostar E3000 platform, while its Ku-band and C-band communications payload was supplied by Thales Alenia Space.

Yahsat Y1A will have a coverage footprint spanning the Middle East, Africa, and Southwest Asia, creating regionally-focused capacity to meet the region's expanding requirements for government, commercial and consumer satellite communication services.  Operating from an orbital slot of 52.5 deg. East, it will support Abu Dhabi's ambition to become a hub for media broadcasting and telecommunications services – enabling customers from Europe and South Asia to connect with customers across the entire coverage area.  

Intelsat New Dawn – which was deployed from Ariane 5's lower payload position at 35 minutes into tonight's flight – is owned by a joint venture of Intelsat and a consortium led by Convergence Partners. This satellite's C-band and Ku-band transponders are to support the communications infrastructure for African customers who have experienced exceptional growth, and contribute to the region's development.  It is tailored for voice, wireless backhaul, Internet and media applications services.

Built by Orbital Sciences Corporation using its STAR-2 platform, Intelsat New Dawn will be integrated with Intelsat's global satellite fleet and stationed at the 32.8 deg. East orbital location.  It was the 52nd satellite launched by Arianespace for Intelsat, the world's leading satellite operator.

Following today's successful mission, Arianespace Chairman & CEO Jean-Yves Le Gall announced the date for its next Ariane 5 launch: a May 19 liftoff from the Spaceport with the ST-2 payload for ST-2 Satellite Ventures Pte Ltd., and the GSAT-8 spacecraft for the Indian Space Research Organisation.

Ariane 5 lifts off from the Spaceport carrying a record payload mass with its Yahsat Y1A and Intelsat New Dawn satellite passengers.

[Salo]

http://www.arianespace.com/news-press-release/2011/4-22-2011-mission-success.asp

Arianespace launch a success: Yahsat Y1A and Intelsat New Dawn in orbit[/size]

Kourou, April 22, 2011

On Friday, April 22, Arianespace orbited two communications satellites: Yahsat Y1A, built by Astrium and Thales Alenia Space for Al Yah Satellite Communications Company PrJsc (Yahsat) of the United Arab Emirates, and Intelsat New Dawn, built by Orbital Sciences Corporation for New Dawn Satellite Company Ltd., a joint venture between Intelsat and Convergence Partners.

201st Ariane launch, 43rd success in a row

This latest successful Ariane 5 launch, the second in 2011 and the 201st Ariane launch in all, once again proves the launcher's operational capabilities. Ariane 5 handles a complete range of missions, from commercial launches into geostationary orbit to spacecraft launches into special orbits. It is the only heavy launcher now on the commercial market capable of simultaneously launching two payloads

This latest mission was the 57th launch of an Ariane 5, and the 43rd successful launch in a row, clearly showing that Arianespace's launch Service & Solutions continue to set the global standard and guarantee independent access to space for all customers, including national and international space agencies, private operators and governments.

Record satellite launch weight

The launcher lofted a total payload weight of 10,064 kg, including 8,965 for the Yahsat Y1A and Intelsat New Dawn satellites, which were released separately into their targeted orbits. This performance sets a new payload record on this orbit for the Ariane launch vehicle.

Supporting major operators worldwide

Arianespace offers the launch Service & Solutions that best match the needs of major operators worldwide.

Yahsat Y1A is the first satellite launched by Arianespace for the United Arab Emirates.

Arianespace and international operator Intelsat have established a long-standing relationship of mutual trust, reaching back more than 28 years. Intelsat New Dawn is the 52nd satellite launched by Arianespace for this leading operator.

Yahsat Y1A/Intelsat New Dawn mission at a glance

The mission was carried out by an Ariane 5 ECA launcher from Europe's Spaceport in Kourou, French Guiana. Liftoff was on Friday, April 22 at 6:37 pm local time in Kourou (5:37 pm in Washington, D.C., 21:37 UT, 11:37 pm in Paris, and on Saturday, April 23 at 1:37 am in Abu Dhabi, UAE).

Yahsat Y1A was built by Astrium and Thales Alenia Space. Weighing 5,935 kg at launch, Yahsat Y1A will provide services for both government and commercial customers in the Middle East, Africa, Europe and Southeast Asia. Yahsat Y1A will be positioned at 52.5 degrees East, and will offer its customers innovative broadband solutions for Internet, business data and high-definition television (HDTV) services. It has a design life of 15 years.

Intelsat New Dawn weighed 3,000 kg at liftoff, and offers a design life exceeding 15 years. Built by Orbital Sciences Corporation, it is fitted with 28 C-band and 24 Ku-band 36 MHz transponders. Positioned at 32.8 degrees East, it will offer a wide range of services for Africa, including Internet, media and data networks.

[Брабонт]

C-band Reflector on Intelsat New Dawn Fails to Deploy

Satellite fleet operator Intelsat said May 3 one of the two principal reflector antennas on its just-launched New Dawn telecommunications satellite has failed to deploy in orbit and that release of the other antenna will await attempts to force the first one to spring loose.

[Salo]

http://www.spacenews.com/satellite_telecom/110603-intelsat-new-dawn.html

Fri, 3 June, 2011
Impaired New Dawn Satellite Also Had Trouble Deploying Ku-band Antenna[/size]
By Peter B. de Selding

    PARIS — The Intelsat New Dawn satellite, whose C-band reflector antenna has remained stuck in folded position since the satellite's April 22 launch, also had trouble deploying its Ku-band antenna, a glitch that may offer valuable clues to the board of inquiry looking into the problem, industry officials said.

    While the Ku-band antenna eventually was deployed the week of May 23, it took hours longer than planned as ground teams overcame an initial resistance that resembled what happened several weeks earlier with the C-band reflector, officials said.

    "They got it deployed — eventually," said one industry official, referring to the initial difficulties in the Ku-band antenna's release. "The problem appears to be more than an issue unique to that one C-band antenna."

    In a June 2 response to Space News inquiries, Washington- and Luxembourg-based Intelsat confirmed that there were issues with the Ku-band antenna's deployment. The similarities could help in the investigation into what happened on the C-band antenna, which is now viewed as likely to remain useless, depriving the satellite of half its broadcasting payload and a yet-undetermined percentage of its planned 15-year service life.

    "The two antenna deployment 'outcomes' appear to be related," Intelsat said in its statement. "The investigation team will issue a report when it has completed its work.  The satellite is operating nominally in all other respects and customer traffic is already transitioning to the satellite."

    New Dawn was built by Orbital Sciences Corp. of Dulles, Va. Orbital spokesman Barron Beneski June 2 said the company would decline comment on the situation.

    New Dawn's broadcast payload is delivered through two elliptical reflector antennas, each measuring 2.5 meters by 2.7 meters. One is linked to the C-band payload, the other to the Ku-band transponders.

    Intelsat said the C-band antenna, whose deployment was planned soon after New Dawn arrived at its test location in orbit, successfully released a series of pins holding the antenna to the satellite's body. But for reasons still unknown, the spring mechanism that should have released the antenna did not function.

    Intelsat held off on deploying the Ku-band antenna for several weeks as it tried gently shaking the satellite, and exposing the stuck reflector to heat and cold, in an effort to deploy it. Those efforts, which while ongoing prevented the satellite's entry into commercial service, were abandoned the week of May 23, at which time the Ku-band antenna was deployed.

    Satellite antennas and solar arrays are stowed for launch to minimize the satellite's volume as it is placed under a rocket's fairing for launch. There are several types of antenna-release mechanisms on satellites, including spring-loaded and motor-driven deployment systems.  

    Intelsat New Dawn now has full utilization of its 16 Ku-band transponders — 24 Ku-band transponders when measured in 36-megahertz equivalence — through the reflector antenna. The satellite is operating from its intended post at 32.8 degrees east in geostationary orbit.

    With the C-band antenna and its 28 36-megahertz transponders now viewed as definitively out of service, New Dawn — owned by a joint venture of Intelsat and Convergence Partners of South Africa — will be limited to no more than half its intended role. New Dawn was scheduled to replace Intelsat's Galaxy 11 satellite at that orbital slot. Intelsat has said Galaxy 11 has enough fuel to continue operating until April 2015.

    Intelsat New Dawn was valued at $250 million including its construction, launch and insurance for its first year in orbit.

    In addition to being deprived of half its broadcasting capability, New Dawn may see its planned 15-year lifespan curtailed. A satellite is designed to fly in orbit with its solar arrays and broadcast antennas fully deployed. The placement of its thruster engines and the size of its fuel reservoir are optimized for a satellite in full-deployment configuration. With one of the two broadcast antennas stuck against the satellite's body, New Dawn likely will require more fuel to maintain its stabilization in orbit, reducing its operating life.

    The extent of the reduction to in-orbit service life is unknown and will likely be the subject of detailed discussions between New Dawn's owners and the insurance underwriters that will be asked to pay what is all but certain to be a claim exceeding $150 million.

[Sharicoff]

С NewDawn идет коммерческий траффик Ku-диапазона. Антенна C-диапазона так и не раскрылась.

[Salo]

http://www.spacenews.com/satellite_telecom/110805-design-defect-new-dawn-failure.html

Fri, 5 August, 2011
Investigators Cite Design Defect in Intelsat New Dawn Antenna Failure
By Peter B. de Selding

 PARIS — The Intelsat New Dawn satellite launched April 24 has been unable to deploy its C-band reflector antenna, depriving the satellite of half its intended functionality, because the antenna's spring-loaded deployment mechanism got caught in the billows of its sun shield, according to industry officials briefed on the issue.

 A review board investigating the problem concluded that the same phenomenon occurred a month after the launch, when Intelsat and New Dawn's manufacturer, Orbital Sciences Corp., attempted to deploy the satellite's Ku-band antenna after abandoning attempts to shake loose the C-band reflector.

 During this attempt, the Ku-band antenna's deployment mechanism also got caught in its sun shield, a thermal blanket that covers the back end of the antenna to protect the satellite from the extreme temperature spikes that occur in orbit.

 But unlike the C-band antenna, the Ku-band reflector had a motor-driven deployment mechanism to permit it to be precisely pointed in orbit to maximize customer use. The thinking was — and this is common to many communications satellite designs — that to fine-point the C-band antenna, the satellite's entire body could be oriented, obviating the need for a second motor.

 Using the motor to move the Ku-band deployment system up and down, ground teams were able to free it from the sun shield. Nearly two months after New Dawn was launched, the Ku-band reflector was placed into normal operations and has since been working fine, Intelsat has said.

 Luxembourg- and Washington-based Intelsat and Dulles, Va.-based Orbital Sciences have succeeded in reproducing the failure on the ground, confirming the hypothesis.

 While satellite structures are extensively tested for fitness in thermal vacuum chambers that simulate the space environment, their antennas are not part of the tests. With antennas deployed, most telecommunications satellites are too big to fit into thermal vacuum facilities.

 Orbital has redesigned its sun shield venting, especially for satellites using the company's larger reflector antennas. New Dawn's elliptical antennas measure 2.5 meters by 2.7 meters. The redesign includes recalibrating the number and placement of vents in the sun shield to permit trapped air to escape.

 It is impossible to rid a satellite of all the air trapped in it. Pockets of air trapped under the sun shield tend to billow in the vacuum of space, and the air is then shed through the vents.

 The antennas have four hold-down points, or clamps, which are released on command. The clamps were placed not on the outside of the sun shield but inside it; the clamps released, but the mechanism designed to deploy the antenna got caught in the billowing sun shield.

 In an Aug. 4 conference call with investors, Intelsat Chief Executive David McGlade said the Orbital-built Intelsat 18 satellite being prepared for launch in October has been subjected to "corrective actions" to assure the New Dawn issue does not recur. Similar measures are being taken for the Intelsat 23 satellite, also built by Orbital, he said.

 The nondeployment of the C-band antenna means Intelsat will need to remove from its contracted backlog all or most of the $310.2 million it had secured for users of New Dawn's C-band capacity, depending on whether Intelsat is able to find replacement capacity on competing operators' satellites.

 The defect also is expected to cost Intelsat about two years of service life for New Dawn. The company's attempts to shake loose the C-band antenna in April and May used about a year's worth of fuel, according to one industry official. The official said New Dawn's commercial life likely will be cut by another year given the fact that it must be flown in a way that was not planned, with the C-band antenna still tucked against its frame.

 Like most modern commercial telecommunications satellites, New Dawn was expected to operate for 15 years in geostationary orbit.

 In an Aug. 5 response to Space News inquiries, Orbital issued the following statement:

 "We've investigated the New Dawn situation with our customer Intelsat and understand why the antenna did not deploy. With that knowledge, we have designed and implemented corrective measures to ensure that it does not happen again."

 Responding to Space News inquiries, Intelsat on Aug. 4 issued the following statement:

 "The Intelsat New Dawn failure review board completed its investigation and concluded that the deployment anomaly of the C-band reflector was most likely due to a billowing of the reflector sun shield.

 "The billowing caused the sun shield to capture the ejection-release mechanism and prevent reflector deployment."

 Intelsat officials have not abandoned all hope of freeing the stuck C-band antenna. In several weeks, New Dawn will enter a period of eclipse, causing a sharp change in thermal environment that might be able to accomplish what could not be done with the previous shaking attempts.