Ok Ernie, here is an example (just happened to have a screenshot with a FMS screen and some restrictions). At MAROM I am flying at 240 kts bacause the global restriction of 240kts below FL100 in descent has kicked in. This works very well and the restriction only applies on passing FL100. Next, I want to fly to HK823 and I have set a restriction (on the LEGS page) that at the point HK823 I should be at 5000ft and the speed should be 220 kts - as I understand it, the entry here refers to the aircraft state, both speed and altitude, as it should be on passing the waypoint in question. The distance from MAROM to HK823 is 15 NM so in the default case where VnavSetSpdRestDist is not set or it is set to 25, I will expect the speed to be set to 220 kts immediately on passing MAROM. However, I set the value to VnavSetSpdRestDist=6 in my cfg file and so now I would expect (and this is what I am trying to achieve) the speed to be held at 240 kts after MAROM until I am 6 NM away from HK823 when the restriction would be applied. This is not what happens; the speed is set to 220 kts immediately after MAROM. Why? Have I misunderstood the use of that variable? In this case the distance between the waypoints in question is short but consider the case that I get an ATC direct to the IAF point which might be still 30 NM away but be specified as 200 kts at 2300 ft... I might still be at FL120 and the FMS setting the speed down to 200 kts already is clearly not right, yet that is what it does!
Geoff
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File comment: Example waypoints and speeds
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