Fsbuild-2 Flight Planner

Hi,

The setting "VnavSetSpdRestDist" should be preventing the speed restriction from being applied until the specified distance from the waypoint but it is not working. I have tried to set this to 6 nm (I have also tried other values) but still the next waypoint speed is always set immediately that the previopus waypoint is passed! Have I misunderstood something? This is annoying as my aircraft has autospoilers and so (unless I intervene manually) the speed for the next waypoint ends up being reached and held rather early in many cases!

Setup: V1.8 Smiths FMS, B712/MD11 ND, custom perf file. I have added the line to the B717_200.cfg file which is called by the gauge (other entries therein work fine).

Thanks,
Geoff

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

So... no response here usually means "you've missed the point, read it again" or "go and search for this in the documentation"...
Am I right in thinking then that the VnavSetSpdRestDist applies only to the restrictions set in the CLMB and DESC phases, and therefore any airspeed 'restriction' set via the LEGS page will simply be applied as soon as that waypoint becomes active? Is this realistic, ie how it happens in reality..? I would have thought the aircraft would maintain current speed and then slow down on approaching the waypoint, but (as often) I could be wrong in that!

Geoff

I didn't miss the point.

I have to investigate it, that takes some time. So I have to make time for it.

I did look at it over the weekend. It doesn't work, like its supposed to. That's the answer.

When the speed restriction is applied the VNAV descent speed becomes that speed so it doesn't go back to a higher speed when the restriction waypoint is met. Apparently what is happening is the descent speed is changing when the waypoint is passed (this is verified on the DES page) basically nullfying distance .cfg setting.

It did work at one time, so probably some other fix inadvertantly broke it.

It will have to be addressed in a future update.

Regards.
Ernie.

No worries - I appreciate you're a busy man! I just wondered if I was missin gomething obvious. Anyway, so the result is that it should be restricting as I expected, but isn't doing so. Good to know and hopefully something you can fix for the next update.

Cheers,
Geoff