SiberianTiger
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EADS Astrium has been selected in January 2006 by Telesat to build the company’s new Nimiq 4 satellite. This is the third consecutive order for a Eurostar E3000 satellite from the Canadian-based operator following Anik F1R and Anik F3. Planned to enter service in 2008, Nimiq 4 will broadcast direct-to-home TV from its orbital location of 82º West.
Nimiq 4 will continue to enhance digital television services in Canada. It will feature 32 active high-power transponders in Ku-band and 8 in Ka-band. The multi-spot Ka-band payload will provide coverage of the most densely populated regions of Canada.
EADS Astrium, as prime contractor for Nimiq 4, will design and build the satellite and supply both the payload and the platform. EADS Astrium’s facilities in the UK Germany, Spain and France and will contribute to the design and manufacture of the spacecraft. Canadian industry will supply a significant part of the spacecraft equipment and technologies.
Nimiq 4 is based on the Eurostar-3000S version of the highly successful Eurostar communications satellite. It will have a launch mass of 4.8 tonnes, a solar array span of 39 meters once deployed in orbit, and spacecraft power of 12 kW at end of life. The double-floor E3000 model is equipped with an all-chemical propulsion system and Lithium-Ion batteries. The satellite, operating in geostationary orbit, will provide commercial services for a minimum of 15 years.
Nimiq-4 Major Characteristics
Application Broadcasting Orbit GEO Orbit Position 82° West Operator Telesat (Canada) Coverage North America Prime Contractor EADS Astrium Platform Eurostar E3000S Design Lifetime around 15 years Launch Mass, kg approximately 4,850 Solar array span, m 39
Nimiq 4 Payload Specifications
Frequency Bands Ku and Ka Transponders Ku-band 32 Ka-band 8 Transponder Power (end of life), kW 12
The ProtonM BreezeM launch vehicle with the Nimiq-4 satellite on board is scheduled to be launched from Baikonur Cosmodrome on 19.09.2008 at 21 h 48 m 00 s UTC (20.09.2008 01 h 48 m 00 s Moscow Local Time )
Program Preview
The launch is provided by International Launch Services (ILS) for Telesat Canada. ILS Mission Statistics: 4th ILS launch of 2008, 47th Proton launch for ILS, 10th Eurostar satellite launched on a Proton.
Nimiq-4 Ascent Profile
Nimiq 4 satellite will be launched according to the proven ascent profile using a standard ascent trajectory and drop zones of the launch vehicle jettisonable parts.
Proton-M Powered Flight
The Proton-M first three stages place the ascent unit (AU), which consists of a Breeze- M upper stage, adapter system and Nimiq 4, into 51.5° inclination suborbital trajectory.
Six RD-275 engines ignite at approximately T–1.6 sec and are commanded to 50 % of nominal thrust. Thrust is increased to 100 % at T – 0 sec. Liftoff confirmation is signaled at T + 0.5 sec. The staged ignition sequence verifies whether all engines are functioning nominally before being committed to launch.
The launch vehicle ascends vertically for about 10 sec. Pitch control, engine ignition and cut-off times, payload fairing jettison times and attitude control are calculated in such a way that Proton-M worked-out stages fall onto nominal drop zones.
The first stage and the second stage separate 123.6 and 331.1 sec after liftoff, respectively.
346.4 seconds after liftoff the payload fairing is dropped on to the second stage booster drop zone. During jettison longitudinal and cross joint clamps unlock, fairing halves are unfolded by means of pushers, following which the halves are broken off. Once in the nominal orbit, the launch vehicle control system shuts down the steering engines, breaks mechanical links between the third and upper stages and ignites solid retro motors in order to withdraw the third stage jettisonable booster.
Proton-M powered flight lasts 584.86 seconds. The AU powered flight begins at the moment of the third stage separation.
Breeze-M Powered Flight
Immediately after the separation of the third stage booster, the Breeze-M stability engines start, damping the angular velocities of the third stage separation and then providing ascent unit orientation and stability during coast flight along a suborbital trajectory to await the first burn.
The upper stage follows a five-burn injection profile. The first burn occurs 94 sec after the separation from the rocket, forming a support orbit.
The second burn is performed in the first ascending node of the parking orbit. After the second burn the ascent unit transfers into an intermediate orbit. The third and fourth burns occur after an AU revolution along the intermediate orbit in the perigee and form a transfer orbit with an apogee close to that of the target orbit. The additional propellant unit is jettisoned during the gap between the third and the fourth burns. The fourth burn takes place 125 seconds after the third one. The fifth burn is performed in the transfer orbit apogee resulting in the target orbit.
Once in the target orbit, the ascent unit is stabilized for Nimiq 4 separation, following which the satellite is released.
After the craft separation GEO parameters are measured, and the upper stage is withdrawn to drift in a safe mode (pressure in all the containers is dropped).
The Breeze-M powered flight lasts 33,080 seconds (9 hours 11 minutes 20 seconds).
Please watch the streaming video either at the International Launch Services' website.
Registered users will be able to access the real time modeled views of the rocket's staging and in-orbit maneuvers, flight graphs, streaming video and audio reports at Khrunichev's Space Centre's COOPI website.
Also, you can read the Nimiq 4 launch blog in real time.
