The #2 hydraulics power the outboard wheel brakes, among other things. #3 hydraulic powers the inboard. (Or other way around) Even if all hydraulic fluid is lost, there is a backup hydraulic accumulator just for the brakes themselves. Still a good decision to return to ATL. I wouldn't want to land on a short runway with only 2 working systems.
Last edited by saxman66; Oct 22, 2016 at 11:08 am