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-   -   BA 744 procedures (https://www.pprune.org/tech-log/350501-ba-744-procedures.html)

B-HKD 11th November 2008 01:21

BA 744 procedures
 
Hey Guys,

I have a question regarding the BA SOP for their 744. Reading PPRuNe I noticed a slighly different procedure BA uses for their 744 regarding take off's, is it correct that all 3 packs will go off for a T/O above 300T and at 3000ft will be selected back to NORM? During engine start pack 1 and 3 will go off ?

Some insight in this particular procedure would be greatly appreciated!

Just a 16 year old 744 fanatic :8

Leo

Pontius 11th November 2008 04:44

You managed to get some of it but not quite all.

All three packs go off for engine start. Just allows more air from the APU to spin the starter motors, rather than trying to keep the cabin temperatures at a reasonable level :}

Above 300T, yes, it's a packs off take-off. Below 300T, packs on. All three packs get turned off for take-off. The packs are turned back on again once Climb Thrust is annunciated as the thrust mode. You put one pack on, let the cabin climb rate settle down and then put the other two on. Most people like to just pop on the second pack, wait a bit and then turn on the third but, strictly speaking, there is no need to wait between the second and third packs.

When is Climb Thrust selected? Depends on the airport and whether it's a noise abatement climb. If it is a noise abatement climb (as is the case in most places nowadays), then Climb Thrust is set at 1000'. If it's not a noise abatement climb then it's set when flap 5 is set. Obviously this is all set up in the FMC ahead of time, so VNAV is engaged after take-off (it's armed beforehand) and then Climb Thrust will automatically kick in depending on what's been set in the FMC.

ZimmerFly 11th November 2008 04:57

What? No more APU to centre pack t/o then?

L337 11th November 2008 06:00


What? No more APU to centre pack t/o then?
That procedure was stopped a couple of years ago. The APU now goes off in the "after starts".

Fuel saving.

The 300T figure is fairly arbitrary, but a figure was needed so that one was chosen. Easy to remember. :p

B-HKD 11th November 2008 11:19


You managed to get some of it but not quite all.

All three packs go off for engine start. Just allows more air from the APU to spin the starter motors, rather than trying to keep the cabin temperatures at a reasonable level

Above 300T, yes, it's a packs off take-off. Below 300T, packs on. All three packs get turned off for take-off. The packs are turned back on again once Climb Thrust is annunciated as the thrust mode. You put one pack on, let the cabin climb rate settle down and then put the other two on. Most people like to just pop on the second pack, wait a bit and then turn on the third but, strictly speaking, there is no need to wait between the second and third packs.

When is Climb Thrust selected? Depends on the airport and whether it's a noise abatement climb. If it is a noise abatement climb (as is the case in most places nowadays), then Climb Thrust is set at 1000'. If it's not a noise abatement climb then it's set when flap 5 is set. Obviously this is all set up in the FMC ahead of time, so VNAV is engaged after take-off (it's armed beforehand) and then Climb Thrust will automatically kick in depending on what's been set in the FMC.
Thanks a lot Pontius, I really appreciate it.

Leo

WindSheer 11th November 2008 11:48

B-HKD

I assume you use PMDG 747-400?

You can practice all that was mentioned on there.:ok:

B-HKD 11th November 2008 14:21

Windsheer,

That is exactly what I will do :8

Thanks again guys,

Leo

B-HKD 11th November 2008 20:34

Flap Setting
 
Is it true that SOP is to use Flaps 25 for landing during normal conditions? So I'm guessing that Autobrake 2 and idle reverse is the norm?

Leo :)

Jetblue190 11th November 2008 21:17

Im pretty sure that SOP is to set flaps to 25 in norm conditions. Not sure about autobrake though. I would assume that they would be the norm also.

Shane :ok:


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