Course to active waypoint on LEGS page 1L

[Hardy Heinlin]

Good evening,

I'm wondering if there is a misunderstanding ...

As we all know, the line title in 1L indicates the course to the active waypoint. That's what the manuals say.

If you are on the leg to the active waypoint, it also displays the course from the aircraft to the active waypoint, not just from the last waypoint to the active waypoint (magenta line). Both sit on the same line.

What if you are offroute? Will it display the course from the aircraft to the active waypoint, or from the last waypoint to the active waypoint?

If it always displays the course of the magenta line, the FMC will give no information in digital form about the current aircraft course to the active waypoint. Without an ND, the pilot wouldn't know where the active waypoint is; the FMC would display the distance only.


Regards,

|-|ardy

[emerydc8]

Hi Hardy. I think it displays the course from the aircraft to the active waypoint, but it would be nice to have someone check this in the sim. Isn't this what PSX does now?

Jon

[Britjet]

Aircraft to active...
Peter

[Hardy Heinlin]

Hi, thanks.

PSX is correct then.

Somewhere, I can't remember where, I read it should display the course of the magenta line (regardless of the aircraft offroute position) if the line is a direct-to line, i.e. if it's a course that has been entered in 6R on the LEGS page for a direct-to.


|-|ardy

[emerydc8]

Hi Hardy,

There was a post from several years back that I can't find now, but we were discussing what happens when you select direct to a waypoint but you do not execute it right away. If I recall, there was some discussion -- and it might well have been resolved -- as to whether the course/distance on the CDU and the white dashed line on the ND continue to update while the EXEC light is illuminated. I checked this out and it looks like the course on the ND is updating about every 5 seconds. So once you select direct-to, but don't execute, it will constantly recalculate the course and ND and take you from your PP direct when you finally do execute. It will not intercept a course from where you first selected direct. I think this was probably resolved but had some time to check it out last night. We were deviating around weather and they cleared us direct PXV when able. I selected but did not execute PXV right away to see what it would do.

https://youtu.be/p8grsOuegNY

Jon

[Hardy Heinlin]

Hi Jon,

yes, this has been resolved. Two years ago, I think. But thank you anyway; such flight deck videos are always interesting!


Cheers,

|-|ardy