Intelsat 508

The Intelsat V spacecraft are 3-axis stabilized to 0.5 deg using momentum wheels. Hydrazine propulsion system. Passive thermal control. Dual solar arrays provide 1800 W BOL, NiCd, or NiH batteries. The communication payload consists of 21 C-Band and 4 Ku-Band transponders for 12000 voice circuits and 2 TV channels. The last five of the nine spacecraft in this block carry a maritime mobile payload (seven additional transponders) for lease by Inmarsat.