New FMC for BA 744s?
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Joined: Aug 2001
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From: Greater Aldergrove
New FMC for BA 744s?
G-CIVS has been doing some patterns around Scotland and Northern Ireland today and yesterday, as BAW9175. One suggestion is that a 747-8 FMC is being trialled for retrofit to the BA 744 fleet. I'm not sure as to the validity of this rumour, but maybe someone here can confirm or otherwise? Also, what benefits would this bring...can the existing 744 FMC manage RNAV for example?
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From: USofA
Highly unlikely that the 747-8 FMC will make into a 747-400. The -8 FMC is filllled with problems at this hour and barely makes the grade for the -8, much less the -400. Very different platform behind the CDU.


Joined: May 2000
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From: Seattle
The 744 can do RNP and P-RNAV. The only thing it MAY not be able to do is RNP 0.3 approaches.
The -8 FMC works fine for most things. VNAV is a bit flaky on the descent, and there are problems with some approaches with tight turns (e.g., MEX). The "barely makes the grade" description overplays the minor problems. Second software update is supposed to be available this week to address most of them.
I have heard previously that the -8 FMS was going to be available for the 400; don't know the cost.
The -8 FMC works fine for most things. VNAV is a bit flaky on the descent, and there are problems with some approaches with tight turns (e.g., MEX). The "barely makes the grade" description overplays the minor problems. Second software update is supposed to be available this week to address most of them.
I have heard previously that the -8 FMS was going to be available for the 400; don't know the cost.
Last edited by Intruder; 16th February 2013 at 15:28.
Usual disclaimers apply!
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From: EGGW
The FMC's do not have the required amount of 'memory' for the aircraft route structure so they are being upgraded, together with FANS.
The other option would have been an absolute nightmare to manage namely an Eastern fleet and a Western fleet.
The other option would have been an absolute nightmare to manage namely an Eastern fleet and a Western fleet.
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From: USofA
Intruder I know your flying the -8, which I am not so you have the hands on advantage. Tell me does the -8 generate Vspeeds for T.O.? I ask this because I spent a few hours last week working on an alternative work around so the -8 instructors could do a demo for the FAA on a 747-8 course. I know that the Instructor cadre at Boeing have few if any good words to say about this FMC. Wonder what give there?


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From: Seattle
Intruder I know your flying the -8, which I am not so you have the hands on advantage. Tell me does the -8 generate Vspeeds for T.O.? I ask this because I spent a few hours last week working on an alternative work around so the -8 instructors could do a demo for the FAA on a 747-8 course. I know that the Instructor cadre at Boeing have few if any good words to say about this FMC. Wonder what give there?
Dunno what problems they are having at Boeing...


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From: Seattle
The 744 can do RNP and P-RNAV. The only thing it MAY not be able to do is RNP 0.3 approaches.
Do you mean <0.3 RNP approaches?
...there are problems with some approaches with tight turns
Or do you mean containment issues on RF turns during 0.3 RNP approaches?
Or do you mean containment issues on RF turns during 0.3 RNP approaches?
Example of the turn problem is the ILS DME-1 Rwy 23L into MMMX. The FMS will not make that last turn to final without significant overshoot, unless we manually intervene. I haven't flown it in the -8, but it's the topic of much company discussion.

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From: on the golf course (Covid permitting)
ILS DME-1 Rwy 23L into MMMX
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From: Stansted
BA are using the -8 FMC. The GSS Chief Tech Pilot has been having quite a few conversations with them as to the "problems" that exist at the moment. As previously stated most of these are due to be fixed at some point.

Joined: Jul 2007
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From: USA
You gotta like that. "Most" of these are due to be fixed. Wonder what casued BA to switch over to this FMC when the Pegasus based FMC in the -400 works pretty good.
Already been answered by gas path:
The FMC's do not have the required amount of 'memory' for the aircraft route structure so they are being upgraded, together with FANS.
The other option would have been an absolute nightmare to manage namely an Eastern fleet and a Western fleet.
The other option would have been an absolute nightmare to manage namely an Eastern fleet and a Western fleet.
The -8 FMC has more memory and thus it is the perfect solution to the problem. And as Intruder has already said, the major firmware revision for the FMC is coming this week.
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From: nowhere
Last edited by JammedStab; 6th May 2014 at 02:00.



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From: Everett, WA
FYI, the 747-8 FMC was always intended to be retrofitable to the -400 (as others have noted, the -400 FMC, designed in the late 1980s, was simply out of capability).
The downward interchangeability apparently caused many of the problems they had with the FMC on the -8. Most of those issues have now been sorted out.
The downward interchangeability apparently caused many of the problems they had with the FMC on the -8. Most of those issues have now been sorted out.




