Descending from FL390 to FL210 was fine when I set the V/S to 2500 fpm on the autopilot. However, when I tried to descend to 2000 using that rate, it just seems to stick with 100 fpm. I tried to redo it by hitting the VS/FA button and reset the rate, but it seems to stick with that 100 fpm. I had to push it down using the joystick. What am I doing wrong?
Thanks.
Try pressing again the altitude knob when changing altitude in the mcp
Just in order to clarify, in the 787, Autopilot features are handled through the MCP (Mode Control Panel), two words for the same thing. Resulting engaged modes are displayed on top of the PFD (Primary Flight Display) for confirmation, in the FMA area (Flight Mode Annunciator)
The MCDU in which we enter the flight plan and other flight data is neither the autopilot
Perhaps did you mentioned another panel ?
This whole part and only this one, is the 787 Autopilot/MCP :
FMA area :
I always use 2500 fpm to both climb and descend. Although for climb, I think we could go higher. I’ve watched videos from real 787 flights and they casually go way over 3000 fpm, the PFD even reached 3300-3400 fpm in some cases.
I noticed that if you set an altitude and the V/S mode, and the target altitude changes for any reason before you reach the previously set value, then you have to press the V/S button again, or else the autopilot will just stop at the original altitude. So by pressing the V/S button again you actually activate the new value. Too bad that nothing indicates this.
We can also press the push button at the center of ALTITUDE knob, if the current altitude displayed on the PFD is different than the one in the MCP ALTITUDE LEDs display
Why would you use VS mode during climb? FLCH mode or VNAV should be used as those are speed based. Climb is normally performed at a constant CAS up to changeover to MACH, the resulting vertical speed is irrelevant.
I don’t know how well VNAV works in default aircraft, or if it works at all, since the flight plan often doesn’t contain altitude data for various waypoints. (I don’t even know if VNAV gets the data from there at all.) Also, I read somewhere in a manual about the usual climb/descent rates up to different altitudes, not to mention looking at some MSFS videos where various YouTubers used various values and techniques. So I think you can say that I assembled my habits from various sources. 
If we fly the default 787, the VPATH is self calculated in the World Map area by the sim, when preparing an IFR flight, based on specific aircraft perfs data. When flying the B787H (GitHub - Heavy-Division/B78XH: B78XH is an open source and free modification of default Boeing 787-10 in Microsoft Flight Simulator.), we have the ability to specify manually speed and altitude at each waypoint, in the MCDU using scratchpad and input entries
Only to be seen on the ND at the moment I believe and predefined alts and speed on legs page
In real life vertical speed is not used for climb, if VNAV is unavailable, then FLCH mode is used.
Thanks for all of your input. It worked using the V/S this time so I don’t know what happened, but definitely I’ll start using the FLCH or VNAV.
