Vnav descent

[Bajermanden]

Am i the only one experiecing very unstable thrust when descending? 

It varies all between idle and 80% 

[aafrench7]

Ya same here. It seems that idle descent causes the speed to roll back too much and VNAV doesn’t compensate with pitch so the AT comes alive with FMC SPD. This cycle then repeats. 
 

 

[samy_k97]

Can both of you say which Aircraft and post a Log.txt here?

[Mobu86]

Same here

[Beaverbeliever]

I am seeing this in the -700 on multiple flights. It doesn't seem like the idle path descent is tuned correctly.

[Bajermanden]

-700

Log.txt

[sab39v]

Same here, -600. 25tons of payload (heavy :))

[ajarilla]

The same here on the -800. Looks like the calculated descent path do not correspond to the given descent airspeed (it's smaller), that way the speed is always decreasing. As the logic is working properly by using vertical speed mode and also VNAV with flaps I believe that the only issue is the descent path. 

[agonyair]

@Bajermanden, experimental flight on in the Xplane settings?