Hi Ernie,
Sorry, late night when I wrote that and not enough information! Here's what I do:
Program FMS with departure route, some waypoints, arrival route and set the following...
CLMB 300kts 250/10000 restriction
CRZ FL360 (or whatever) /.77 -> gives M077 cruise - works fine
DESC 300kts 240/10000 restriction
On the arrival route, I then put something like this in the LEGS page:
ENRT0 300/140 <- not set by me WAYP0 240/9200 <- not set by me WAYP1 240/6000A WAYP2 220/4000A WAYP3 200/2300A
The last three then have altitude and speed restrictions set by the FMS...
Now what happens is this:
CLMB to CRZ happens fine and the gauge does set the M077 speed so I know that works (and TOC is seen). Then CRZ to DESC is also fine, because if I set a lower altitude just before TOD, the descent is initiated on scedule.
Passing ENRT0 at 300kts and roughly the right level - ok Passing FL100 before WAYP0, the DESC page restriction kicks in and there is no problem. Passing WAYP0, the restriction of WAYP1 should get applied -> ie still 240kts. However, here I get the 330kts problem. If I now disengage ISG VNAV long enough to set 240kts, then re-engage it, I get my 240kts speed ok but only until passing WAYP1 etc etc.
This is clearly not right, and the odd thing is that in my FS9 version the same problem does not occur. I can code up some restrictions so that the ISG speed cannot exceed a certain set of height based speeds on the descent / approach legs, but then tht defeats the object of having the FMS set restrictions anyway.
Note: The fact that I get 330 as the set speed is possibly because other code will prevent the AP from commanding a speed greater than the barber pole value - 10 kts (during that phase of flight). It could be that ISG is sending an even crazier (higher) speed to the FS!
I'll do another test and post some screenshots later.
Cheers, Geoff
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