PDF SOP 747-400

[John H Watson]

The AOM says the pitch command is a target speed of V2 (IAS/Mach Window) +10 or airspeed on rotation. If the current airspeed remains above the target airspeed for more than 5 seconds, that becomes the new target airspeed  (up to a maximum of V2+25)

VNAV doesn't engage until 400' at which point the FMC holds the airspeed at current airspeed (until accel height).

Rgds
JHW

[Hardy Heinlin]

Does your AOM explicitly refer to "IAS/Mach Window"?

If I recall correctly, there were some maintenance docs explaining this stuff in greater detail; this also involves VR: if I'm not wrong, the pitch need not only be higher than 2°, the current IAS also needs to be greater than VR (if valid). If the AFDS gets VR data from the FMC, why shouldn't it get V2 as well (if valid)?


Cheers,

|-|ardy

[Stephane LI]

Nice document.
In the Boeing FCOM, the normal procedure in the before start procedure flow is to set V2 for the IAS/Mach Selector on the MCP.

Stephane

[Hardy Heinlin]

I know, Stephane. But the question is if the AFDS really takes the MCP SPD as V2 or if the AFDS takes the V2 from the FMC if it's valid. The fact that the crew sets V2 on the MCP and that the MCP SPD agrees with the FMC's V2 doesn't necessarily mean that the MCP is really the one that feeds the AFDS with a V2 reference.


|-|ardy

[Britjet]

Quoting from the FCOM2...

"• After takeoff, the AFDS commands a pitch attitude less than the pitch limit indicator to maintain:
• a target speed of V2 plus 10 knots or airspeed at rotation (pitch attitude greater than two degrees) plus 10 knots, whichever is greater
• if current airspeed remains above the target speed for 5 seconds, target airspeed resets to current airspeed, to a maximum of V2 plus 25 knots
 • IAS/MACH window speed if IAS/MACH window speed is changed to a speed greater than the target speed

Note: AFDS uses the speed set in the IAS/MACH window for V2."

Peter

[Hardy Heinlin]

"Note: AFDS uses the speed set in the IAS/MACH window for V2."

OK, confirmed :-)


|-|ardy

[John H Watson]

P.S. My FCOM doesn't add a note at the end, but inserts it into the earlier text with parentheses.

I'm not sure how Vr fits into this. You would think the speed shouldn't drop below a certain value, but the guidance has to be independent of FMC entries during TO mode (for when the FMC is inoperative). On the other hand, maybe it's just not that smart. Stall Card computed stall speed may be the only lower limitation.

[double-alpha]

Hi,

I found this interesting discussion : B744 MCP Airspeed Setting (V2 Versus V2+10)

http://www.pprune.org/tech-log/283956-b744-mcp-airspeed-setting-v2-versus-v2-10-a.html

[John H Watson]

Actually, I was aware of this PPRuNe posting  :mrgreen:  I was just wondering what your source was and whether a certain American airline was still using the V2+10 setting (in contravention of Boeing ops)

[double-alpha]

Hello,

It mainly comes from Boeing (who uses of course V2).
I decided initially to choose V2+10 (anyway V2 in the new PDF) when I loaded departure.situ from instructor page to take some screenshots of the MCP speed setting : you can notice that the MCP speed is already set to V2+10 (if you assume that V2 in TAKEOFF REF page is correct!).

I do not know for American airline or other...

Regards

Adrien

[DougSnow]

Actually, I was aware of this PPRuNe posting  :mrgreen:  I was just wondering what your source was and whether a certain American airline was still using the V2+10 setting (in contravention of Boeing ops)

Pre-Merger NWA was V2
UAL is V2
DAL is V2
CKS is V2
GTI is V2

An airline can ask Boeing for whats called an "NTO" - No Technical Objection, so maybe this carrier had done that.

[double-alpha]

Thank you dougsnow for the clarification

[double-alpha]

Hi,

I didn't fly yesterday (I am OFF!) so I had time to write a third version to make it more clear, simple and understandable (I hope) :
https://www.dropbox.com/s/d72oxcs3uvzpwlu/747_sop2.pdf?dl=0

It seemed to me that a few items were a bit confusing  or not relevant for the first virtual flight (INBD CRT selector:EICAS...)
In addition, I noticed one or two omissions (for exemple : maintenance panel checks, AFT CARGO HT as required after start, ...)

I tried also to be more coherent with PROCEDURES section you can read in Hardy Heinlein manual page 554 (for exemple : STANBY POWER test that you can find only in FCOM supplementary elec procedures = removed).

I removed flap speed additives that don't exist in boeing SOP (SOP request to set MCP to flaps maneuvering instead of flaps maneuvering speed + 10 kt).


You can download a PDF file of my "visual" keyboard summary : it could be helpful if you use keyboard only for your first flights.
https://www.dropbox.com/s/9rgv0mobp9xfmv8/psx_keyboard.pdf?dl=0

[G-CIVA]

Just one further point if you have time before you go to press for a further iteration ...

pp 27 Automatic Engine Start Sequence

Boeing FCOM & All Airline SOP dictate the Start Selector is pulled BEFORE the Fuel Control is positioned to RUN.

It might be helpful here to also add in a section for PW equipped aircraft not fitted with AUTOSTART (SQ & UAL) immediately spring to mind.  

In addition a sequence for a Manual Start might be helpful.

Just some thoughts.

[double-alpha]

Mistyping error, fixed soon , tky

BUT, In Hardy Heinlein Aerowinx Manual, I checked (autostart) :
1 fuel control switch RUN
2 engine start switch PULL

2 then 1 in my FCOM

Hardy, Could you confirm ??

[G-CIVA]

From a 'vanilla' Boeing 747-FCOM Vol 1 Normal Procedures, Engine Start Sequence:

https://www.dropbox.com/s/n8gixlrvls7v6rn/ENG%20Start.jpg?dl=0

Also move this vid fwd to 3m 45 sec to see the procedure in action.

https://youtu.be/nhXXjNybx6A

[double-alpha]

OK we have now for Engine Start sequence :

1 engine start switch PULL
2 fuel control switch RUN

[G-CIVA]

Check!

 

[Balt]

Hi,

this is very well done, thanks! Couple of points for refinement:

I'd recommend on initial flight deck prep (page 3) to also check the brake accumulator pressure, and always set #4 HYD demand pump to AUX, never OFF (in the cold and dark cockpit anyway). This is because the ground handling bus powers this pump (as does the APU). The accumulator itself was not designed to stop the airplane. While there may be some pressure left, it may not be enough to keep the airplane from rolling once the chocks (or tug) are removed... embarrassment ensues. Unless Hardy didn't model that, which I consider unlikely. :-) Once brake accumulator pressure has been confirmed, re-set the parking brake to make sure there's enough pressure on the disks.

The second point regards the AC packs: I don't think takeoffs are ever performed with all the packs off, at least not in my memory. Usually two packs are switched off, but one remains on. After all we want a pleasurable 500fpm or less cabin rate. I can't find anything in my old manuals regarding all packs off for performance, but it is of course conceivable that you might just squeeze that extra rounding error out of your takeoff calculations...

Cheers

- Balt

[cavaricooper]

BA used to be 300T+ packs off (my current MO).  If it has changed, perhaps Peter can advise current status.....?

C