Montag, 9. Dezember 2013 - 07:00

Raumfahrt - Start von Proton-M mit Inmarsat 5-F1-Satelliten

The three-stage Proton-M booster rolls out, ahead of Sunday’s planned Inmarsat 5-F1 launch. Photo Credit: ILS

Proton-M Rolls Out to Baikonur Pad Ahead of Sunday Launch

Less than a month since it successfully delivered a military communications satellite into orbit on behalf of the Russian Government, another venerable Proton-M booster stands ready at the Baikonur Cosmodrome in Kazakhstan, tracking a liftoff at 6:12 p.m. local time (7:12 a.m. EST) Sunday, 8 December. Rollout of the vehicle to the pad took place earlier today (Thursday, 5 December). The mission is being conducted under the auspices of International Launch Services (ILS), a joint U.S.-Russian organization, based in Reston, Va., which operates all Proton-M flights out of Baikonur. It will transport the 13,000-pound (5,900-kg) Inmarsat 5-F1 satellite into geostationary transfer orbit for the U.K.-headquartered International Maritime Satellite Organisation to provide up to 15 years of global mobile broadband communications for deep-sea vessels, in-flight connectivity for airline passengers, and high-resolution streaming of video, voice, and data.

This is the first of three Inmarsat-5 satellites ordered from Boeing in August 2010 for the purposes of providing faster worldwide broadband services. (A fourth was ordered in October 2013 to serve as a spare.) Each satellite is equipped with 89 Ka-band beams with flexible global coverage, whose key objectives include mobile broadband communications for deep-sea vessels, in-flight connectivity for airline passengers, and the streaming of high-resolution video, audio, and data transmissions. Since its formation in 1979, Inmarsat technologies have been employed for disaster relief and the distribution of aid, most recently providing telecommunications support in the catastrophic aftermath of Typhoon Haiyan in the Philippines. A pair of five-panel gallium arsenide solar arrays will provide the satellite buses with sufficient electrical power—about 15 kilowatts at the start of the mission and 13.8 kilowatts at the end—to support some 15 years of orbital operations. A xenon ion propulsion system will be utilized for stationkeeping.

Built in the United States, the Inmarsat 5-F1 spacecraft arrived at Yubileiny Airfield, near Baikonur, on 11 November, aboard an Antonov-124 transport aircraft. The flight had already experienced delays, due to rough weather over Canada and Iceland, and after touchdown the satellite’s container was maneuvered into a railcar for transfer to Hall 92A-50, where it arrived early on 12 November. “The offload requires highly skilled manpower,” ILS explained, “to meticulously transfer the [spacecraft] safely off the railcar, unpack it from its container and place it onto the payload adaptor for the fit check.” Over the next few days Inmarsat 5-F1 underwent rigorous testing, and on 15 November the restartable Briz-M upper stage for its mission arrived at Yubileiny Airfield. With the Briz-M housed in Hall 101 and the Proton-M vehicle itself in Hall 111, all hardware was on-site as the pre-launch campaign gathered momentum.

All components of the Proton-M, including its three main stages and the Briz-M, are fueled by a mixture of nitrogen tetroxide and unsymmetrical dimethyl hydrazine. Loading of these propellants aboard the Briz-M—whose single engine has the capacity to restart on up to eight discrete occasions to inject payloads into orbit—has already taken place, and the Russian State Commission formally granted approval for rollout to the pad on Wednesday, 4 December. With today’s successful rollout, and engineers entering Day One of Countdown operations, the pace will quicken in anticipation of Sunday’s launch.

Based upon previous timelines, fueling of the Proton’s three stages should get underway about nine hours before liftoff, which is presently scheduled for 6:12 p.m. local time (7:12 a.m. EST). The rocket’s first stage consists of a central oxidizer tank, surrounded by six outboard fuel tanks, each fed by an RD-276 engine, and these will provide the initial impetus to boost the mission toward space. At T-5 minutes, the Briz-M upper stage will be transferred to internal power and will confirm the health of its systems. Ignition of the six RD-276 engines will commence at T-2 seconds, ramping up to 100 percent of rated performance to produce 2.3 million pounds (1.04 million kg) of thrust at the moment of liftoff.

A little over a minute into the ascent, the Proton will encounter a period of maximum aerodynamic stress (known as “Max Q”) on its flight surfaces, and the separation of the first stage is timed to occur at the two-minute point. The vehicle’s second stage will then pick up the baton, with its four engines generating a combined 540,000 pounds (244,950 kg) of propulsive yield for a little over 3.5 minutes. Soon after second-stage separation, at T+5 minutes and 47 seconds, the Payload Fairing (PLF) will be jettisoned and the single-engine third stage will add a further 138,000 pounds (62,600 kg) of thrust for the next four minutes of flight. Shutdown of the third stage should occur at T+9 minutes and 42 seconds, by which time the vehicle will have been established onto a suborbital trajectory.

The turn will then come for the Briz-M, which has exhibited a mixture of success and failure since its maiden voyage. In August 2012, a premature shutdown of the Briz-M left Indonesia’s Telkom-3 and Russia’s Ekspress-MD2 satellites in useless orbits, and in December 2012 another launch glitch impacted the Yamal-402 satellite. Last March, a Proton-M/Briz-M successfully injected Mexico’s Satmex-8 communications satellite into orbit, and on 29 September another vehicle lofted Astra 2E. It has also performed flawlessly during October’s launch of Sirius FM-6 and again during last month’s flight of Raduga-1M-3. Capable of restarting up to eight times in flight, the Briz-M has a battery-powered lifetime of 24 hours and is scheduled to execute five “burns” to insert Inmarsat 5-F1 into orbit.

“The Briz-M will perform planned mission maneuvers,” noted ILS in its press kit for Sunday’s mission, “to advance the orbital unit first to a circular parking orbit, then to an intermediate orbit, followed by a transfer orbit, and finally to a supersynchronous transfer orbit.” The burns are calculated to last 4.5 minutes, 19.5 minutes, 9.5 minutes, 8.5 minutes, and 3.5 minutes. Assuming an on-time liftoff, the payload should be injected directly into its geostationary orbit about 15 hours and 31 minutes into the mission and should communicate with ground stations shortly thereafter.

Although Sunday’s mission will be the seventh Proton flight executed by International Launch Services (ILS) in 2013, it has been a troubled 12 months for the family of launch vehicles, which traces its heritage back to the 1960s and which has supported 391 missions. Built by the Khrunichev Research and State Production Centre, it has one of the most reliable track records of any rocket in the world, but suffered a dramatic and highly embarrassing launch failure on 2 July, seconds after liftoff. It was the Proton’s first catastrophic malfunction during first-stage flight in over 30 years and prompted several months of corrective actions and cutting managerial and organizational changes. In August, the Russian government formed the United Rocket and Space Corporation to consolidate the space sector, with Deputy Prime Minister Dmitri Rogozin announcing that it was “so troubled that it needs state supervision to overcome its problems.” A few weeks later the Proton returned triumphantly to flight on 29 September, delivering the Astra 2E communications satellite into orbit, and restored its reliability credentials in October with the Sirius FM-6 launch and last month with the Raduga-1M-3 launch.

Encased within its protective container, the Inmarsat 5-F1 payload is removed from the Antonov-124 carrier aircraft on 12 November. Photo Credit: ILS

Quelle: AS

Update: 23.10 MEZ

Quelle: Roscosmos

Description and Purpose:
Four Boeing 702HP satellites will provide new Ka-band high-data-rate mobile communications services.

Customer:
Continuing a relationship spanning three decades, Inmarsat, the leading provider of global mobile satellite communications services, returned to Boeing in August 2010 to order three 702HP spacecraft to provide its new Ka-band global and high-capacity satellite services. In October 2013, Inmarsat exercised the option to order one more 702HP spacecraft to add to their fleet.

General Characteristics:
The new satellites will join Inmarsat's fleet of 10 geostationary satellites that provide a wide range of voice and data services through an established global network of distributors and service providers.

Each Inmarsat-5 satellite will carry 89 Ka-band beams that will operate in geosynchronous orbit with flexible global coverage. The satellites are designed to generate approximately 15 kilowatts of power at the start of service and approximately 13.8 kilowatts at the end of their 15-year design life. To generate such high power, each spacecraft's two solar wings employ five panels each of ultra triple-junction gallium arsenide solar cells. The Boeing 702HP carries the xenon ion propulsion system (XIPS) for all on-orbit maneuvering. When operational, the Inmarsat-5 satellites will provide Inmarsat with a comprehensive range of global mobile satellite services, including mobile broadband communications for deep-sea vessels, in-flight connectivity for airline passengers and streaming high-resolution video, voice and data.

In a separate arrangement, Boeing also entered into a distribution partnership with Inmarsat to provide L- and Ka-band capacity services to key users within the U.S. government. Leveraging Boeing's expertise in government environments and applications, the Inmarsat-5 satellites will provide Inmarsat's customers with an array of secure voice and high-speed communications applications between land, sea and air services, and multinational coalition. The Inmarsat-5 spacecraft will be compatible with the Ariane, Sea Launch, Proton and Atlas launch vehicles.

Miscellaneous:
Beginning in 1976, Boeing has built three satellites and four payloads for Inmarsat. Marisat 1, 2 and 3 were three L- and C-band communications satellites built for the space segment of the world's first maritime system. Of the three Marisat satellites, all exceeded their contractual design life of five years and provided a combined 70 years of service. The HS-356 spacecraft were launched in 1976, one each on February 19, June 9, and October 14. The satellites were placed in geosynchronous orbit at 15 degrees west longitude, 176.5 degrees east longitude, and 72.5 degrees east longitude, respectively. Boeing also built the L-band payloads that launched on the four Inmarsat-2 satellites during the early 1990s and continue to operate without a single unit failure to date.

Quelle: Boeing

Update: 7.12.2013

Update: 8.12.2013

Inmarsat begins Global Xpress roll-out

The roll-out has begun for Britain's single biggest commercial space project.

The London-based Inmarsat company has launched the first spacecraft in what will be a new global telecommunications network for its on-the-move customers.

Inmarsat plans to launch up to three further spacecraft in its Ka-band Global Xpress (GX) system, representing an investment of £1bn ($1.6bn).

The initial I-5 F1 satellite was launched from Baikonur in Kazakhstan.

Its Proton rocket left the pad at 18:12 local time (12:12 GMT) on a long flight due to last over 15 hours.

Separation from the Proton's Breeze-M upper-stage on Monday (GMT) should put the I-5 in a supersynchronous transfer orbit that runs out to 65,000km above the planet.

The Boeing-built, 6.1-tonne satellite will then use its own electric propulsion system to circularise this trajectory and move itself into a "stationary" position at 63 degrees East, some 36,000km above the Indian Ocean.

Inmarsat has become the dominant force in the so-called Mobile Satellite Services (MSS) market.

Its principal customer base is the shipping sector, but the company also caters for any groups that need connectivity away from a fixed line. These include oil and gas installations, the aviation sector, armed forces, aid agencies and NGOs in disaster areas, and TV news crews reporting from trouble zones.

Customers can use Inmarsat services to make phone calls, to transfer audio-visual material or simple data.

Traditionally, the company has served these customers using the L-band part of the radio spectrum. However, the new GX constellation will operate in the higher-frequency Ka-band, enabling much higher bandwidth connections - up to 50Mbps download, and 5Mbps upload.

"When we started thinking about this project five years ago, we'd come to the conclusion that you could not grow much further the L-band franchise - not in terms of revenue, but in terms of capacity," explained Ruy Pinto, Inmarsat's chief technical officer.

"We have hit the limits of all-you-can-eat high-data-rate packages in L-band; there simply isn't enough spectrum. Ka is the natural next step to deliver the types of packages our customers want," he told BBC News.

The I-5 satellites will not replace the existing Inmarsat L-band spacecraft; rather, they will augment them, and hopefully also drive new types of services.

Although Ka will accommodate higher data rates, its signals can become degraded in poor weather, and Inmarsat plans to switch customers seamlessly between the bands if some locations on the globe are experiencing particular difficulties.

"The physics of Ka allows higher throughput. It has had a vulnerability in the past because of its susceptibility to 'rain fade', to bad weather, but technology has largely taken care of this problem," added Inmarsat's Michele Franci.

"And for the maritime sector, where you might experience extreme weather, we offer a service onboard the ship where you have a router that is connected to the network management system and chooses Ka or L-band depending on the strength of the signal."

One key and fast-growing market likely to benefit from the introduction of the Global Xpress system is the aviation sector.

Inmarsat already provides mobile connectivity to enable airlines to offer on-board wifi for passengers. Ka should mean those passengers can do more on their laptops, tablets and smartphones while in the air.

Of all Inmarsat's revenue streams, this one is currently growing fastest - in double digits.

Three satellites, separated from each other by roughly 120 degrees, are required to complete the GX network. Inmarsat will launch the I-5 F2 and F3 models next year, with the aim of having 90% of services up and running by the end of 2014.

The company has also exercised an option to buy a fourth spacecraft from Boeing.

This additional platform will initially provide insurance against any failure in the first three, be that a loss on launch or a major malfunction in orbit. But the intention is certainly to put it in orbit at some point.

Richard Roithner from the space consultancy Euroconsult said the GX roll-out was a big moment for Inmarsat.

He told the BBC: "With this trend towards the higher data-rate needs of customers, Inmarsat has increasingly faced competition from Fixed Satellite Service operators, such as Intelsat and SES with what is called VSAT in the Ku and C-band. This has taken away some high-end customers.

"These operators are all now thinking about their next-generation, high-throughput systems. And in the future, Intelsat will probably be the main competition with a system called Epic," he said.

Quelle: BBC

Quelle: Roscosmos

Update: 9.12.2013

Russian Proton-M rocket puts Inmarsat-5F1 satellite into sub-orbit space

A Russian Proton-M rocket and a Breeze-M upper stage have successfully guided a fresh telecoms satellite into sub-orbit on Sunday. "The spacecraft and the upper-stage rocket have detached from the third stage of the carrier rocket," Russia's space agency has reported.

After being launched from Baikonur in Kazakhstan at 12:12 GMT by a Russian Proton-M main booster, the Inmarsat-5F1 telecommunications satellite of the British Inmarsat global mobile operator is on its way to a geostationary transfer orbit up to 65,000 km above the earth. It is expected to settle into this orbit on Monday morning after detaching from the Briz-M upper booster at 3:43 UTC. The Briz booster is yet to be fired five times to psoition the satellite.

The Khrunichev company that developed the Proton and Briz systems says the detached booster will immediately be deactivated to prepare it for safe dead orbiting.

From its transfer orbit, the Inmarsat-5F1 satellite is to proceed to a geostationary position

Proton to launch UK telecom satellite from Baikonur

A rocket Proton-M with the British telecommunications satellite Inmarsat-5F1 will be launched from the Russian spaceport Baikonur on Sunday, the press service of the Khrunichev State Space Research-and-Production Centre said.

"The launch of the telecommunications satellite Inmarsat-5F1 is scheduled at 16:12 Moscow time on Sunday, December 8, from the Baikonur spaceport," the press service reported.

The telecommunications satellite Inmarsat-5F1 will be launched according to the already tested method of orbiting the satellite.

The first three stages of the rocket Proton-M will put the upper stage rocket Briz-M onto a suborbital trajectory carrying the telecommunications satellite Inmarsat-5F1. The upper stage will then bring the satellite to the designated orbit. After that the telecommunications satellite Inmarsat-5F1 will shift to its geostationary orbit by means of its engine and will assume it's position at 63 degrees east longitude.

The British telecommunications satellite will separate from the upper stage rocket 15.5 hours after the launch.

The Inmarsat-5F1 satellite was produced by the U.S. company Boeing Satellite Systems based on the BSS-702HP platform for the British satellite communications operator Inmarsat Plc. The launch weight of the satellite will be more than six tonnes.

The Proton-M launch vehicle is an upgraded modification of the rocket Proton-K with improved energy-mass, operational and ecological features. The first launch of the rocket Proton-M with the upper stage rocket was on April 7, 2001.

The Russian-U.S. joint venture International Launch Services Inc. (ILS) was contracted to launch the Proton rocket.

Quelle:Voice of Russia

Launch Proton-M Inmarsat 5-F1

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