On Tue, 3 Oct 2000, Ron Lee wrote:
> GE-1A 35725 x 217 km
> 1 26554U 00059A 00275.97042671 -.00000238 00000-0 00000-0 0 25
> 2 26554 48.5427 349.9203 7291408 0.0363 0.1310 2.28521338 06
> GE-1A Blok-DM r 35823 x 7394 km
> 1 26557U 00059D 00276.42872861 -.00000208 00000-0 00000-0 0 17
> 2 26557 15.9434 352.8128 5078951 359.3738 336.5518 1.85446958 28
Actually, GE 1A has followed the standard launch profile for commercial
launches of the four-stage Proton-K.
The first Blok DM3 burn places itself and the satellite into a GTO which
is usually inclined at ~51.6 deg (the same inclination as the LEO), but
sometimes the plane is changed by ~3 degrees. This is the orbit tracked
and issued for GE 1A.
The second Blok BM3 burn varies from one mission to the next and is
carefully chosen to split inclination change and perigee-raising so that
the velocity change required by the _satellite_ to reach geosynch drift
orbit is minimised. Since western satellites are generally 1-1.5 tonnes
heavier than the Russian satellites launched to GEO, the Proton-K cannot
place the commercial payloads into GEO: hence the trade-off. This is the
orbit listed for the fourth stage.
For those of you who get the Journal of the British Interplanetary
Society, I'll plug my paper on four-stage Proton-K launch profiles which
describes the rationale behind this profile, with graphs to illustrate the
minimum satellite velocity change requirement: JBIS, May/June 2000, pp
197-214.
Phillip Clark
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Phillip S Clark 22 Winterbourne Close
Molniya Space Consultancy Hastings
Compiler/Publisher, Worldwide Satellite Launches E Sussex TN34 1XG
U.K.
Specialist in "space archeology" - the older and more obscure the more
interesting it is !
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