V speeds

[Beardyman 604]

Departure airport and runway given, thrust limits set, perf init set, flaps value 10, CG 21% set - still FMC do not calculate V speeds and trim value.

What am i doing wrong ?

[VHOJT 162]

Hi.  Check the options.  There is an option for FMC calculated V speeds

[Beardyman 604]

it's 'on'

[NBL5370 4]

make sure you have confirmed perf page

[Mike777 163]

 

 

Departure airport and runway given, thrust limits set, perf init set, flaps value 10, CG 21% set - still FMC do not calculate V speeds and trim value.

What am i doing wrong ?

 

Are your ADIRUs (inertial navigation) aligned?

 

Mike

[Copper. 78]

1) Check perf init... make sure data is inserted, complete and correct.

 

2) insert cg on takeoff ref... assuming CDU preflight is done correctly, you will get v speeds like everyone else

 

3) if all else fails, fly the tutorial.

[emvaos 13]

You also need a departure runway defined.

 

I assume you have not seen V-SPEEDS UNAVAILABLE which means you are outside the envelope of the aircraft.

[andreh 125]

I assume you have not seen V-SPEEDS UNAVAILABLE which means you are outside the envelope of the aircraft.

 

^^If you select a derate and is too heavliy loaded v-speeds will be unavailable

[KORDATC 80]

Also, make sure you hit the LSK 1L next to Gross Weight in the Performance page. This happened to me last night. Since I'm used to flying the NGX, I tried to go and enter a ZFW. On the queen however, the ZFW is already pre-populated. Instead you have to verify the Gross Weight indication by pressing LSK 1L. After doing this, the V-speeds appeared.

[GrantWolf 0]

Also, make sure you hit the LSK 1L next to Gross Weight in the Performance page. This happened to me last night. Since I'm used to flying the NGX, I tried to go and enter a ZFW. On the queen however, the ZFW is already pre-populated. Instead you have to verify the Gross Weight indication by pressing LSK 1L. After doing this, the V-speeds appeared.

I had the OP's problem and this fixed it for me. Recommend check this

[regis9 3,999]

And I think that varies by aircraft/operator configuration? Tonight I flew the United -400 and I had to confirm the GW value, I'm pretty sure I didn't have to do that in the Cathay Cargo -400F last night.

[Beardyman 604]

I think "Best Answer" title should go to KORDATC

[Bert Timmerman 0]

Gross weight may be too high for flaps 10 take-off. Set flaps 20 and v-speeds will be calculated.

 

Bert Timmerman

[fince 1]

Had the same problem, KORDATC was spot on, thanks mate.

Paul Findlayson

[scandinavian13 5,192]

Yeah, this is one that catches people out on a number of occasions.

Don't pencil-whip your pre-flight. Go through your normal procedure, but make sure you're paying enough attention to the info being shown to you. The GW will have a < next to it, meaning that it needs to be confirmed. Slow down, don't rush. Be one with the airplane.