Originally Posted by
CincoDeMayo
Blue is your Emergency Generator, its not the RAT. More Airbus redundancy.
The RAT will power the blue electric system in an emergency. Its the entire point of the RAT, to power the emergency electrical if both engines are lost, as well as the APU. So if you lose all electrical/engine generation, the RAT works to power the blue.
So if you have an ECAM telling you to to take the Blue elec pump to off, the RAT will still power the Blue system for emergency electrical in the event the RAT is deployed.
So taking the Blue HYD Elec pump offline is not taking the RAT or the Emergency Electrical offline as well.
You don't need the blue pump. But if memory serves the RAT is actually not a generator like on other planes... it's a hyd pump that powers the blue system, including the emerg gen which is hyd powered. So you do need blue fluid, plumbing, and reservoir in order for the RAT to power the gen.
I'm uncomfortable flying around business as usual without the blue system, since that's both your last ditch hyd and elec... both of which are required to control the plane. I could live without the blue pump.