As I am unfamiliar with the 777 ( only the 747-200 & -400 ), are the CWT fuel boost pumps "override" pumps, as in the type that will put out more pressure than the mains?. And if so, is there any limitations to having them on below a certain volume?. Could there be any possibility that CWT fuel ( mabye unscavenged fuel ) at highpressure was feeding/cavitating both engines?. Would only the pump cavitate, or would air be induced into the system?
I know SOP would most likely have had Center tank emptied by now, and pumps switched off, but again I'm looking for a "common feed" so to speak.
Again, I am unfamiliar with the 777, and I know there is a wealth of knowledge spread ( unevenly ) amongst those who peruse this forum.
The CWT pumps put out more pressure/flow than the wing pumps. Low pressure output at the CWT either due to the pumps being switched off or due to no fuel in the tank will cause the check valves on the CWT pumps to close, preventing air getting into the manifolds. Like the 744, this process will occur well in advance of landing. Remaining fuel is scavenged via jet pumps (and as discussed previously, this process completes well before a normal landing).
I believe someone asked earlier.... There is no gravity feed for the CWT.
As far as the kudos for the "wonderful" job the Autopilot did...
If I were handflying this approach, and lost thrust, would I sacrifice altitude for airspeed ( to prevent a stall ), damm fckng right I would.
...but if pulling back on the stick with the stickshaker ringing in your ears for a few seconds longer meant narrowly missing a large building (and you knew there was a flat surface beyond)? Wouldn't you take the chance that all those built-in margins for stall might work in your favour on that particular day?
Personally, I think man is a gambler... He is taught what is impossible, but when faced with a large immovable object, he goes for the impossible
