Originally Posted by
FastFlier
BBC are reporting a final partial Inmarsat handshake ping received at 08:19 following the routine handshake received at 08:11 with no explanation. I'm not familiar with 777 systems, but could this have resulted from a transient power interruption during bus transfer following the loss of a genny?
Could be a loss and recovery of the Left Main AC bus. The radio pack would wake-up and send an "I'm here" message skyward.
could it be engine wound down no gennies, rat came on then satcom tried to fire up
When the RAT is deployed after a loss of APU/Engine generator power, the only AC power on the aircraft comes from a small capacity static inverter. This supplies the AC standby bus which powers a few critical items, SATCOM not being one of them.