744 Circuit Breaker Panels (BA&SQ)

[NSEU]

Gents...

I'm trying to map out some CB locations for various 744 configurations, but I'm missing a few details.

The British Airways Wiring Schematics, ref SSM 24-54-07, list two different CB's at the same location on P6 (grid J-18)

"ENG START AIR CONT(C395)" & "AC STBY PWR-TEST-APU BAT (C10572)".

The latter relates to Standby EFIS switching (found on airlines such as Singapore and British Airways)

This conflict is partially resolved as RR-powered 744's don't have "ENG START AIR CONT" CB's (AFAIK, it's a GE and PW thing), but this doesn't necessarily mean that British has the "AC STBY PWR-TEST-APU-BAT" CB at grid J-18. Some airlines (e.g. Singapore Airlines should have both CB's because they have P&W and Standby EFIS switches). Unfortunately, I haven't worked on SQ or BA for a while, so I can't check this out for myself.

Thanks for any insight.

Cheers.
NSEU

[gas path]

As the BA a/c arrived in 'batches' there are some differences in C.B locations. just to complicate matters there are also some errors in the AMM for C.B locations as well!

[NSEU]

Thanks, Gas Path.

just to complicate matters there are also some errors in the AMM for C.B locations as well!

That's true. I've noticed that myself. The Wiring Diagram Manuals seem to be the most reliable (and they put the "AC STBY PWR-TEST-APU-BAT" CB at J18).

Hopefully someone can tell me where SQ puts theirs.

Cheers.
Ian.

[spannersatcx]

RR have START/IGN CONT cb on p6

[NSEU]

RR have START/IGN CONT cb on p6

To name but a few ; )

.. and I have no idea where I'm going to get information on exotic beasts such as ERF's.

[SMOC]

Just got off a BCF ex SQ, J-18 is ENG START AIR CONTROL will have to get back to you for the RR and the ERFs.

[NSEU]

J-18 is ENG START AIR CONTROL

I figured as much. So what have SQ done with "AC STBY PWR-TEST-APU BAT (C10572)"? :confused:
BA has theirs at J-18.

Curiouser and curiouser.

Thanks.
Cheers.
NSEU

[MATMAX]

NSEU-IAN,
As per my experience , both Airbus and Boeing manuals in general get mistakes ...("errare humanum est").
Moreover , all a/c are modified until their "end" of ops , i mean that some can be modified and some not and some can have different options.
Thats the reason why , i always check the effectivity first.
Thats the reason why , you usually find an adress from the manufacturer at the beginning of the manuals for any comments.
(who said that the manuals were "the Bible" ?).
Cheers.

[SMOC]

P&W -400ERF. (CX)

J-18 is ENG START AIR CONTROL

G-14 is AC STBY PWR-TEST-APU BAT

Rgds

[NSEU]

Brilliant! Thanks guys : )

I add that to my diagrams. I suspect G14 is also AC STBY PWR-TEST-APU BAT on the CF6, also.

Cheers.
Ian/NSEU