[/QUOTE]Concerning, selecting a set of gear back up on the good system after having done an alternate gear extension according to the QRH where both gear are selected down with the Alternate Gear Extend Switches.[/QUOTE]
I had a sim instructor at one point that said if for example, #4 hydraulics had failed and all gear had been extended with the alternate system(uses two switches, one for each hydraulic system) as per the QRH, if the weather deteriorated and now you had to go to your alternate with little fuel remaining, you could deselect the single alternate Gear Extend switch that controls the three gear legs powered by #1 system and then select the gear handle up to retract the Nose and Body Gear powered by number 1 system resulting in less fuel burn to your alternate.
Or similar if the other hydraulic system had failed and such a scenario was encountered. I would guess that his scenario is based on hydraulics being completely cut off for the system that still has the Alternate extension switch connected or an assumption of no hydraulic fluid left on the failed system.
So, I guess a question would be....what exactly happens when an Alternate Gear Extend Switch is selected to Alternate?
Last edited by JammedStab; 3rd Jan 2015 at 22:26.