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FLX/MCT
23rd Apr 2008, 17:23
Hi all pilots out there,


i recently read the "A380 Briefing for pilots" which you can also find on smartcockpit.com.
Chapter Autoflight mentions a pushbutton called "VV" which is described as velocity vector. The pb is at the same position as the button for the FD on former Airbus models (direct under baro ref).
Unfortunately (for me at least :rolleyes:) the use and function of "velocity vector" is not further described in the document. I realy have no idea what it could represent except my only guess: to enable/disable the thing I know as speed trend vector, but I cannot imagine that AI made an extra button for this.:confused:

So I ask you if you have any ideas what that could be for.
BTW a great forum - my first post ;)

I am looking forward to your answers

best regards from LOWL
lukas

Diaz
23rd Apr 2008, 18:08
Only a vague guess- perhaps it adds velocity vectors to the PFD?

FLX/MCT
23rd Apr 2008, 18:15
Could you please describe what you understand under velocity vector?

singleseater
23rd Apr 2008, 18:41
I would imagine it is the same as the flight path vector on the 777 and as fitted in most modern electronic flight decks.
The symbol shows where the present flight path will take the aircraft, a very very useful thing. So if you put the symbol on the horizon, the aircraft will fly level, reguardless of speed power nose att combination.
Similarly, if you put it 3 degrees below the horizon, you will descend at 3 degrees, reguardless of wind, speed etc.
Uses inertial and air data to figure it out. I personally use it all the time, even if just monitoring the A/P.
Stay safe and watch out for gravity

FLX/MCT
23rd Apr 2008, 19:45
thanks for answering singleseater! on the airbus aircraft you activate the "bird" and the flight path director (recommended on airbuses for NPAs) via the HDG-VS/TRK-FPA button above the AP master switches. And tha 380 has this one at the same position, too. So I thought that the velocity vector is not the bird but maybe you can use the button to engage it aditionally in HDG-VS mode with the common FD bars.......

FLX/MCT
24th Apr 2008, 15:41
Thank you very much for your answer. :ok:
Another nice advantage of the 380 in my opinion to show the FPV in HDG/VS mode.

regards
lukas

212man
24th Apr 2008, 16:14
Not Sure about the FPA etc : hopefully you'll just pick up the LHR ILS!!!

View from the back is ok..... "http://i202.photobucket.com/albums/aa50/S92ctc/DSC_0129.jpg" border="0" alt="Photobucket"