International Launch Services orbits Echostar IV by Proton
MOSCOW - A Proton rocket orbited the U.S. Echostar IV direct-
broadcasting satellite from the Baikonur Cosmodrome in Kazakhstan on
Friday, marking the return to service of RSC Energia's Block DM3 upper
stage after the stage failed on its previous commercial launch attempt.
The launch occurred from Baikonur Site 81 at 3:45 a.m. Moscow Daylight
Time (17:45 p.m. on May 7 EDT). The three-stage Proton vehicle, built by
Khrunichev State Space Center, inserted the Block DM3 forth stage with the
Echostar IV satellite attached into a low parking orbit.
At the first northbound crossing of the equatorial plane the Block DM3
engine ignited for nearly 400 seconds to raise apogee to geosynchronous
altitude and to lower the orbital inclination. Six hours and 19 minutes
after launch, the Block DM3 reignited at apogee for another 110 seconds to
further lower orbital inclination down to about 15 degrees and raising the
perigee to about 7,700 kilometers.
After separation from the kick stage Echostar IV will perform a series
of independent maneuvers using its on-board liquid-fueled rocket motor to
get into geosynchronous orbit, achieving final orbit on May 12. After that
the satellite will undergo a series of checks over 30 days before being
commissioned for regular commercial operation.
Successful insertion of Echostar IV into GTO rehabilitated the Block
DM3 stage after the launch failure last December. Earlier in April similar
Block DM stages, with slightly different modifications, also successfully
orbited a group of Iridium satellites and the Russian Cosmos-2350 early
warning satellite.
Deputy Director of Khrunichev Alexandr Lebedev emphasized that the two
latest Proton launches were performed within nine days. The launch of
Echostar IV was the 252nd for the Proton rocket since 1967 and its tenth
commercial mission for a foreign customer since April 1996.
Echostar IV is fourth satellite owned by the Echostar company of
Englewood, Colo., and the second built by Lockheed Martin
Telecommunications on its most advanced A2100AX satellite bus. (Echostar 1
and 2, launched in
1995 and 1996, were based on Lockheed Martin's Series 7000 bus.)
Echostar IV, weighing about 3,470 kilograms at liftoff, carries a
total of 44 transponders arranged into two even groups with 16 active and
six backups in each. It will be positioned in the main Echostar slot at 119
degrees West longitude, together with Echostar 2. Echostar 1, currently
also located in 119 degrees West, will be moved to a now-empty location at
148 degrees West.
With the introduction of Echostar IV in regular operation, Echostar
will be capable of broadcasting up to 500 television channels over North
America. Currently Echostar has about 1.3 millions subscribers to its
"Digital Sky Highway" (DISH) Network.
Echostar Chairman Charles Ergen said that after successful launch of
Echostar IV the company will begin seeking a vendor to deliver Echostar V.
This satellite could be orbited in about two years to provide direct
broadcasting in the Ku- and Ka-bands.
Charles Lloyd, President of International Launch Services, which
managed the launch, said that during upcoming four to five months ILS plans
to orbit four more satellites on Proton - Astra-2A for SES; Telesat DTH for
Telesat Canada; Telstar for Loral and a platform for PanAmSat. During the
subsequent 12 months eight to nine more satellites are scheduled for launch
by Protons for ILS.
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