Why no VSR

You're looking at the FMS tab's flight plan preview.  Go to the MAP tab and the VSR is one of your datablocks.

(I'm glad you posted a picture!)  Not sure how else I might have known.


Edited by DavidBunin - 17 Jan 2016 at 7:06am

The VSR datablock on the map page was also blank. It does work some of the time, and indeed started working after I passed the next waypoint. A similar thing happened on an earlier flight yesterday - I had a constraint on the next waypoint after the one I was tracking to and had a VSR. I then went direct-to the next waypoint and the VSR disappeared, even though the target altitude and position were unchanged.

The reason you're not getting a VSR is because the altitude constraint is defined as "at or above".  Since you're above the constraint altitude, you've met the constraint and no altitude change is required.  Therefore, there is no VSR.  If you changed the constraint to "at" or "at or below", you would get a VSR value.

 

Note that an at-or-above constraint in an approach is treated as an "at" for purposes of VSR computation, thus providing vertical speed required to cross each constraint at the lowest legal altitude.  In all other kinds of procedures, however, we'll use the specific constraint kind for VSR.

Clyde doesn't a TOD mark the point FROM which you start a descent. I would expect the VSR to appear once you reach that point.

Isn't the point of the TOD also dependent from the preferred VSR set up in the FMS set up menu?

Then I have only one exaplanation: in your first picture OK has no altitude restriction so the VSR is calculated to BMR. In the second picture you are very close to your TOD and you are most probably at an altitude which is very close to your preferred VSR. I have seen in the SIM that you need to move the altitude ruler a bit to get the VSR to display again, there is some tolerance in there in my view.

Try your second example again by placing the aircraft further away and select an altitude on the ruler which would require a clear altitude change.

Those two screenshots were taken seconds apart - the altitude was unchanged, the VSR would have been almost the same in the second one. All I did was select BMR and hit direct-to. Exactly the same thing happened in flight on that approach - I don't really care what the simulator does, and in flight  "placing the aircraft further away" isn't an option!

AviJake wrote: Ahh yes, we can improve that on the next big round of software updates.   It all comes down to how the system recognizes the waypoint in the sequence.  If it's inside the procedure side brackets or outside the procedure brackets.  Inside the brackets, the VSR datablock is populated, outside it is not in your IAF example.

Cool Beans!