Author Topic: B737 Vapp calculation method  (Read 5166 times)

Offline tango4

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B737 Vapp calculation method
« on: October 25, 2012, 01:01:28 PM »
Hi,
I have a question regarding the way TOPCAT calculates Vapp on the 737.
I use TOPCAT for perf calculation with PMDG NGX 737-800.
In boeing documentation (Flight Crew Training Manual), the method they give to calculate Vapp is to take Vref, and add half of the headwind component, plus the difference between gust and steady wind, with of course some other subtleties.
The fact is that TOPCAT gives me very surprising results , and you cannot specify a gust value for the wind.
I'd like to know how this speed is calculated by TOPCAT ,and why it is different from the Boeing way (or at least, seems to be).

Best regards to all.

Charles MOULIN
LFPG ATC

Offline tango4

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Re: B737 Vapp calculation method
« Reply #1 on: November 12, 2012, 08:52:43 AM »
Any help ? Pleaaaaaaaaaaaaseeee  ;D

Offline tango4

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Re: B737 Vapp calculation method
« Reply #2 on: August 31, 2013, 01:06:13 PM »
Now that PFPX is released, perhaps someone in the dev team will find one minute to answer this question !!
Pleaaaaaaassssse. !

Anyway, I guess I'll buy PFPX in a matter of days....

Cheers everyone and enjoy this new release which looks awesome !

Offline Pierre95

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Re: B737 Vapp calculation method
« Reply #3 on: August 31, 2013, 01:40:01 PM »
Hi Tango4,

a Dev team member will soon answer to your question.

Cheers
Pierre

Offline tango4

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Re: B737 Vapp calculation method
« Reply #4 on: August 31, 2013, 08:29:39 PM »
Thanks a lot Pierre !
I did not want to bother them too much, I know it must have been busy months for them, and you too.
I think I might buy PFPX tomorrow, if I have enough time to start using it. Otherwise, it won't be long anyway !


Offline erum

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Re: B737 Vapp calculation method
« Reply #5 on: November 04, 2013, 11:20:42 AM »
Where can I find the latest aircraft database.  I'm using the latest TopCat, but there are several aircraft not listed.
erum

Offline tango4

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Re: B737 Vapp calculation method
« Reply #6 on: April 01, 2014, 05:21:17 PM »
Just trying to bump the topic, still waiting for an answer... :)

Offline Pierre95

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Re: B737 Vapp calculation method
« Reply #7 on: April 02, 2014, 09:38:58 AM »
Sorry for delayed reply.

TOPCAT doesn't take half wind into account for any VApp or VRef.

The latest addition in aircraft database is PMDG777.

Best Regards
Pierre