View Full Version : B744F Q's
Crossbleed
21st Jul 2008, 13:39
Never thought to ask before, but, why does the freighter lack the AUX HYD DEM Pump on system 1?
And does the ERF have the same 10 tonne tank in the guts as the Pax version?
gas path
21st Jul 2008, 13:50
Never thought to ask before, but, why does the freighter lack the AUX HYD DEM Pump on system 1?
Customer option I believe, as are electric demand pumps on systems 2 and 3.
Our 744Fs do have Aux on both 1 and 4 systems
spannersatcx
21st Jul 2008, 17:44
And does the ERF have the same 10 tonne tank in the guts as the Pax version? What 10 tonne tank in the guts?
AC Aux pumps are optional on sys 1, some have them some don't, CX doesn't as you have to pay! Same with the electric demand pumps on 2 and 3. Although on the ERF I don't think you have a choice.
point8six
21st Jul 2008, 19:43
Boeing customise the B744 according to the customers wishes - hydraulic preferences being one of them. However, I do not know of any Freighter that has a 10 tonne tank in the stab (is that what you mean by "guts"?). The 747 classic (BA '36' versions) only had an aux. pump on No.4 system, for push-back reasons. Having an Aux. pump on No.1 as well allows you to start in sequence 1234 or 4321 - autostart options aside.
esreverlluf
21st Jul 2008, 22:23
I suspect Crossbleed may referring to the 10 000kg auxillary fuel tank installed forward of the centre tank in the 747-400ER. I believe that this can also be installed on the freighters as a customer option.
:O
Dan Winterland
22nd Jul 2008, 02:46
Aux pump on sys 1 is an option regardless of whether it's a freighter or pax aircraft.
The original build Fs don't have the sab tank. If you're loading that much fuel, your payload is going to be reduced. It makes much economic more sense to stage the aircraft with more payload. My company's BCFs have the stab tank pumbing removed to save weight.
Crossbleed
22nd Jul 2008, 08:09
Thanks for the replies everyone.
Every "F" I've operated was absent the AUX DEM on Sys1. (BCF,SF etc..)
Just wondered what quantity and where the ERF stored the extra.
As esreverlluf pointed out, the pax ER have it fwd of CWT "in the guts", pardon my crude vernacular.