Well,is SES-1 a 3,170 kg craft (that is what OSC says, "launch mass"),or a 2,561 kg satellite (as ILS mentions it´s "separated mass")?Maybe it´s with and w/o fuel?YoursThomas
http://www.ilslaunch.com/assets/pdf/SES-1-MO-final.pdf1st stage 123 s >>> I think, Proton will be Phase II (Same as Intelsat-16).