Rest assured that if Optus tries to shift B3 to B1 and then shift B1 to B3 orbital locations it will be a lawyers-at-ten-paces fest.<br /><br />Facts are that B1 and B3 are identical, they both have identical SCPs (satellite control processors) on board. There is nothing to say that the SCP on B3 will not fail tomorrow - chances are more likely for this now that B1 primary SCP has failed. B1 was launched may months before B3 so the probability of B3 failure is now higher.<br /><br />The SCP failure is brought about by a phenonomen called "dendritic growth". Circuit boards are normally covered with a sealant before integration into the satellite. If the sealant is not total, any exposed solder will, under near vacuum conditions of space, start to grow tiny whiskers (or dendrites) of the metal tin. (tin is one of the metals in solder). These whiskers grow in a random direction and sooner or later have grown near to the ground pin/plane on the circuit board. This results in an instantaneous plasma discharge, causes an extremely high current flow which causes the fuse supplying power to the SCP to blow. Bye bye SCP. <br />The ground controllers at Belrose then have to command the standby SCP into service. Hopefully it works, as it's fuse could have been blown for the same reason.<br />The SCP status is not telemetered to the ground control so fingers crossed the standby works!!<br /><br />Take a look at a posting to do with "problems for UBI" on the subject of satellite failure.<br /><br />Keep the faith.....