"The left FCU will do the same for sys 4.
So I would guess the answer to you original Q must be the flap handle RVDT and the PFM in the FCU."
Thanks (to all). It's the PFM that I'm interested in.
Is it smart enought to not run the pumps if,
say, Flaps 1 is selected (from up) ...as the leading
edges won't require hydraulics (I guess I should
now redefine my question to only include RR-
powered aircraft, which, as a rule, don't seem to
have the Flaps Out of Up logic). Is the PFM also
magic enough to know when, say, the inboard
TE's only are running out/in (say due to a
drive failure or flap transmitter failure) and will
only run the respective hydraulic system for those
flaps it can control or see the position of.
The logic is probably so complex, I doubt I would
simulate this on the ground (using a real aircraft)..
and I wonder if the accuracy of a simulator would
be able to mimic the failure of specific flap position
transmitters. If there are any RR-powered 744
pilots out there, you may be able to provide the
first piece(s) of the jigsaw puzzle.... Do the ADP's
operate when the L/E flaps are extended to
Flaps 1 in the air? (by observing the Hydraulic
synoptic during this period).
Thanks again!
Cheers.
Q.