crossfeed...open or closed?
I am hoping that someone can help me understand the crossfeed a little better. I was watching a film about the A330 that had the fuel leak while over the North Atlantic causing both engines to stop after all fuel was exhausted. They didn't initially believe what the airbus computers were telling them and they went through some checks and placed the crossfeed to "on".
My question is this: Is there a difference between the crossfeed in an Airbus v a Boeing? I have read information about the Boeings in my studies and it appears that the crossfeed is always open or they will get a "fuel config" warning. I believe the only time they close it (if I remember correctly what I was told) would be if the tanks were not balanced correctly. Also, the checklists for Boeing (that I have seen) always lists the crossfeed open after the engines have been started.
If the information I have read is correct, why did the flight crew on the Airbus open the crossfeed more than five hours into the flight? I would think their QRH book would have instructed them to close the crossfeed.
Please remember that I am only a lowly student just beginning to take flying lessons. I don't pretend to know all of what I am talking about. I only know what I have read in my books and what I have learned from all of you here.
Cheers!