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B744 MCP Airspeed Setting (V2 Versus V2+10)

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B744 MCP Airspeed Setting (V2 Versus V2+10)

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Old 14th Jul 2007, 01:52
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B744 MCP Airspeed Setting (V2 Versus V2+10)

Dear sirs/madams...
I'm currently looking for 744 airlines which use an MCP window speed of V2+10 for takeoff (rather than V2).
I was wondering if someone could help me complete the following list.
British Airways V2
Japan Airlines ?
Lufthansa V2
United V2+10
Qantas V2
KLM V2
Singapore Airlines ?
All Nippon ?
Korean ?
Cathay Pacific V2
Thai ?
Malaysian ?
Air France ?
Northwest ?
China Airlines ?
Eva Air?
Virgin Atlantic V2
Air China ?
Air India ?
Air New Zealand V2
Additional:
Aerolineas Argentinas V2
Cargolux V2
Thanks for any insight.
Regards.
NSEU

Last edited by NSEU; 24th Jul 2007 at 03:07.
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Old 14th Jul 2007, 14:23
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Aerolineas Argentinas (747-475) V2
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Old 14th Jul 2007, 15:37
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Cathay also V2
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Old 14th Jul 2007, 23:41
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Question

I'd like to ask another question.

Where did you get the idea that anybody would set other than V2??

Liability being what it is, why go outside the manufacturer's recommendations?

G'day
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Old 15th Jul 2007, 01:39
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NSEU,
Suggest you edit your original post adding the new info as you receive it. Otherwise this thread will become unmanageable/unreadable.
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Old 15th Jul 2007, 03:47
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"Where did you get the idea that anybody would set other than V2??"

It has been mentioned on other aviation forums, both for the 744 and 767. I believe some American airlines use it, but I haven't been able to confirm which ones.
I can see how having the command airspeed bug set at V2+10 would provide an airspeed target after liftoff (probably a more reliable target than the FD), but this would require you to make a mental calculation of V2 if you had an engine out.

" Liability being what it is, why go outside the manufacturer's recommendations?"

I agree, but airlines still do modify procedures.

Cheers.
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Old 15th Jul 2007, 05:04
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I can see how having the command airspeed bug set at V2+10 would provide an airspeed target after liftoff (probably a more reliable target than the FD), but this would require you to make a mental calculation of V2 if you had an engine out.
On a normal all engine liftoff Boeing recommend a rotation rate ( around 3 degrees / sec on most types )to an initial Pitch attitude. This will give you an initial speed of between V2+15 to V2+25. This speed should be held until cleaning up the A/C. Also the Pitch Flight Directors cannot be used from liftoff until the mode changes from TOGA/TOGA to THR REF/VNAV SPD at 400', at this time they command your current speed ( within V2 to V2+25 limits)
If you suffer an Engine Failure on or before rotate then a slightly slower rotation rate to the recommended Pitch attitude ( 2 to 3 degrees less than normal ) should give you V2 to V2+15. ( V2 absolute minimum ) once again hold this speed until 400' and THR REF/VNAV SPD then the Flight Directors will command your current speed ( within V2 to V2+15 limits ) until cleanup.
The Bug should not be set to anything but V2 and I know that Boeing would not agree to any Airline changing their procedure in this respect.
I agree, but airlines still do modify procedures.
They do under Boeing and Airbus's ok, but not in this case.
CX, KA, QF, BA, NZ, MH, SQ, JA, etc etc ALL set V2.
It's not rocket science.
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Old 15th Jul 2007, 08:28
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Seems like a waste of technology having to ignore the FD...

Here's how my training notes see it..

"The pitch command is an attitude reference until the vertical speed is 600'/min. With the vertical speed between 600 and 1200fpm, the command is a mix of attitude and speed command. For greater than 1200fpm, it is a speed command. This vertical speed requirement gives windshear protection. The takeoff airspeed reference is as follow:

1) The greater of the airspeed at rotation+10kts or V2+10kts. If the airspeed exceeds this value for 5 seconds, the reference becomes the lesser of current airspeed or V2+25kts.
2) If an engine fails, the reference is the airspeed at engine-out with a lower limit of V2 and an upper limit of V2+10.
3) If a higher MCP speed is selected, the reference increases to that speed.

For takeoff with an engine out, the operation is similar, but the attitude/airspeed mix function occurs between 0 and 600fpm."

At 400', if VNAV is armed, we know that current airspeed is used.

Did Boeing decree that the FD could not be used for takeoff... or is this a pilot/airline thing?

Thanks.
NSEU.
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Old 15th Jul 2007, 12:30
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Geez man your getting way to complicated, although it sounds about right, although the upper limit on the 400 and 777 is V2 + 15 for eng out and V2+25 all engines. It's a rather complicated section in the FCOM 1, and rather dry reading!!
In CX we use the standard Boeing way, the FD's do not give correct pitch info with TOGA after liftoff until VNAV engages at 400'. This is the way on the 777 anyway. I think the 400 was the same. (Anyway it's only a 5 to 6 second wait)
So, on a normal T/O nail 15 deg on a 772 and 12.5 deg on a 773. Eng out nail about 10 deg on both. After a nice slow rotation it will give you the right speed.
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Old 16th Jul 2007, 01:23
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There is a procedure I've just been made aware of....
"It is called enhanced t.o. speeds and it is done by dispatch in (place) of assumed t.o. temps......not quite often used. Boeing talks about this in some of their CBTs and basically they bump speeds as much as 10 kts."
However, it's clearly different from setting V2+10 for all occasions
If the FD is truly ignored (procedures-wise) for the first 400' then what does it really matter what you have dialled in on the MCP? I presume that VNAV (above 400') will be using the V2 you entered on your TAKEOFF REF page, and not the MCP value.

"although the upper limit on the 400 and 777 is V2 + 15 for eng out and V2+25 all engines."

If this is what CX manuals say about the 747-400, then perhaps there are autopilot variations (I'm not surprised.... I remember that Cathay had a unique Rad Alt callout for the Kai Tak approaches). I've always understood that the 777 and 767 are +15kts and the 744 is +10kts. Our 744 AOM, Boeing Maintenance Manual and Engineering Training Notes are not ambiguous on this. Perhaps you could recheck your notes?

Thanks.

Rgds.
NSEU

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Old 16th Jul 2007, 03:58
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I've just been told that United Airlines uses V2+10 (and V2+15 for the 767). Would any United pilots like to comment on this issue? (are there any situations where you wouldn't use V2+10... e.g. high weights, hot day, high altitude, etc)

Thanks.
NSEU.

Last edited by NSEU; 16th Jul 2007 at 04:25.
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Old 16th Jul 2007, 06:27
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MCP Speeds

Air NZ policy is V2. If ATC are forecasting a microburst situation, V2 is set per performance manual speeds - i.e. Normal V2, but VR is set to the performance limited GW rotation speed, not to exceed actual GW VR + 20. The answer to your question is still V2 on the MCP.
But who would take-off if there was a microburst warning? Not me, dude
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Old 16th Jul 2007, 11:29
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Perhaps the 'enhanced t/o speeds' you refer to are also known as 'improved climb procedures' ?
What does your airline use for the MCP speed setting during pre-flight set-up? I would suggest you follow that, as it is your airlines' S.O.P.. If you use V2 + 10 as a pre-flight speed, then you run the risk of climbing out at v2 + 10 following an engine failure after V1, which is not the correct speed. If you need to climb out at V2 + 10, it is displayed on the FMC.
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Old 16th Jul 2007, 11:37
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I've just been told that United Airlines uses V2+10 (and V2+15 for the 767).
Who told you that?
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Old 16th Jul 2007, 12:32
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"Who told you that?"

It was a person involved in aviation training videos who has contact with a UAL pilot. Another source has just told me that V2+10 is shown in (circa 1997) UAL manuals and training information (also, in UAL 757 manuals) but there are also variations in some of the training information (with no explanation).


I heard several years ago (probably in the mid-nineties) that at least one airline used V2+10. The matter resurfaced on a PC simulator internet forum, and I wanted to see if any of the "real world" pilots could shed some light on the matter (didn't make sense to me 10 years ago, either). I also wondered if UAL training/procedures had influenced other carriers. Even though this is only of general interest to me ... I'm not questioning my own airline's procedures... it would be nice to resolve this issue once and for all ( 10 years is a long time )

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Old 16th Jul 2007, 13:34
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MCP V2 or V2+10

Hola NSEU -
xxx
Your suspicions about UAL are absolutely right.
xxx
Please be aware that US air carriers have the dubious idea of not using Boeing publications such as the FCTMs or AOMs. They all consider that "they" know better than Boeing how to fly airplanes. These airlines publish their own "translations" of the Boeing bibles with generally questionable results. Through my long career on the 747 Classic with PanAm and now Argentina, I have collected the 747 manuals from a few US air carriers, and while PanAm's or TWA's are quite well published, some are notoriously poor... the worst I have seen are manuals... from UAL.
xxx
Anywhere I have been in the world, and traded info (or seen manuals) of other operators, all were published by Boeing, and quite similar, the manuals just reflecting the "differences" for each customer airline.
xxx
I have the Boeing original AOMs Vol.1 and 2 from Argentina, Varig, Singapore, Qantas, Air NZ, Cargolux and KUSS Group airlines, and other than specific differences such as engines (PW, GE or RR) or "switchology", the normal, or emergency procedures remain absolutely similar.
xxx
Even check-lists are similar, here and there with one line or two differences. The similarities are such that you can take a pilot trained with Qantas SOPs, and test him in simulator with an Argentina crew and their SOPs, there will be no major differences. But do not try that with a UAL or a NWA pilot...
xxx
As I am not trained in the 747-400, I can only mention what it is for the Classic 747-200/300 or SP... but I can smell where the UAL idiosyncracies would surface, or coming from any other USA airline... Even UAL I remember, has different "aircraft limitations" than standard...
xxx
Do you know that it is possible, with Boeing AOMs and SOPs, to "mix and match" pages of the manuals, and make them compatible, including the numbering of each chapter and pages therein...??? - I had to do that a few years ago, when my airline in Argentina had leased 747-200/300s coming from Singapore, Varig and Qantas...
xxx
I am certain that it is the case with the 747-400 Boeing publications.
xxx
Gentlemen, you also mention different V speeds, these deal with "improved performance" when excess runway is available. In the 747 Classic, you merely select the V2 of the "improved climb". In any case, for the Jurassic 747, we do not use the flight director for pitch control until... 400' AGL...
xxx

Happy contrails
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Old 18th Jul 2007, 13:48
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During takeoff, the TO/GA pitch mode commands 8* nose up until airborne. When airborne, pitch commands change to the lessor of 15* nose up or slightly below the PLI.

As climb rate increases, pitch commands change to maintain the MCP IAS/MACH window speed plus 10 Knots. This speed is V2 for takeoff.

However if you do not perform a text book rotation and maintain the desired pitch attitude exactly for more than 5 seconds are more, the speed will settle on the MCP +10 to a maximum of V2 + 25. This is the case usually with me when i am flying, but as i like to tell my FO's, what is a few knots between friends.

My company uses V2, but as Boeing designed the acft. for V2+10 , so there is no need for using any other speed than calculated V2 according to Mr. Boeing.
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Old 19th Jul 2007, 01:33
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One caveat .. V2 is relevant for OEI but not necessarily for AEO. For the latter we need to ensure that the AEO flight path stays above the calculated OEI flightpath so that a failure doesn't compromise our situation. AEO climbout at V2, especially in a twin, makes for a big pitch down requirement in the event of a failure during second segment ...

The trick is to fly the bird like the OEM recommends in the AFM or FCTM etc ...
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