The upcoming 4/25/05 Zenit 3SL launch by Sea Launch
will boost the 6 metric ton Spaceway 1 satellite
directly to geosynchronous transfer orbit using a
single Block DMSL upper stage burn. I think this
is the first time Sea Launch has done this profile.

At any rate, Spaceway 1 will, if successful,
slightly better the previous commercial comsat mass
record established last month by Inmarsat 4-F1,
which was launched atop Atlas V AV-004 from Cape
Canaveral.

This record, in turn, is set to be beat in June
when 6.1 ton Spaceway 2 is boosted to orbit by an
Ariane 5ECA from Kourou.

- Ed Kyle