Pmdg 777 Sp1 Vnav Descent Issue

[tatin 0]

Hi,

on my latest flights I´ve been experiencing something weird. At the very beginig of the descent, just after reaching the TOD, I get a "drag required" message, even if I am going a bit slow and high on the VNAV Path. Then, fmc speed drops to 0. I disengage the A/P, handfly it a little bit, reset the F/Ds, and then, after a couple of times doing this process, i leave the A/P on, but i control myself the vnav speed, pressing the speed knob. 

Finally, when I reach FL200, approximately, everything goes back to normal and works as expected. 

I know it isn´t a pilot error, because before the SP1, I did the same things and procedures, but this didnt happen.

Thanks in advance for your help!

[McLaren 42]

Hi,

on my latest flights I´ve been experiencing something weird. At the very beginig of the descent, just after reaching the TOD, I get a "drag required" message, even if I am going a bit slow and high on the VNAV Path. Then, fmc speed drops to 0. I disengage the A/P, handfly it a little bit, reset the F/Ds, and then, after a couple of times doing this process, i leave the A/P on, but i control myself the vnav speed, pressing the speed knob. 

Finally, when I reach FL200, approximately, everything goes back to normal and works as expected. 

I know it isn´t a pilot error, because before the SP1, I did the same things and procedures, but this didnt happen.

Thanks in advance for your help!

 

Are you programming anything in the Decent Forecast. That info will determine your TOD and could be throwing off the calculation with incorrect information. 

[mohamed abdellatef 0]

that happened to me

[tatin 0]

Are you programming anything in the Decent Forecast. That info will determine your TOD and could be throwing off the calculation with incorrect information. 

i program myself the descent forecast. i did this before the SP1, but it didnt happen

[Ianir 0]

Any fix???? 

[downscc 1,327]

You didn't provided enough information to try to duplicate problem.

 

Full names required here, thanks.

[jwill919 0]

Perhaps it used to do it automatically, I've only had this problem since I upgraded to SP1c last week and I get all my plans from Simbrief.com