Autopilot - Altitude selector / alerter slaving

[amahran 608]

Flying in the twin otter, I'm noticing some non-physical behavior between the alerter and the autopilot panel: the alerter should only act as an alerter, but the altitude in the alerter and the autopilot are slaved to each other:

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Of course, as you see above, changing the altitude in the autopilot panel changes the altitude in the alerter window. The alerter window doesn't have a control mechanism to automatically adjust the selected altitude.

 

My recommendation is to remove the slaving of both altitude values from each other, and leave the alerter on the left as an independent alerter instrument (for annunciation) while the autopilot altitude is the one that controls the autopilot.

[MarkHurst 173]

The KAP140 has its own alert functionality, which is what the Collins one is slaved to. It's slaved both ways, so you can preselect the altitude on the upper dial too if you want. The alert light isn't implemented, though. I suppose you could have two independent alerters, but it doesn't seem to make much sense.

[amahran 608]

7 hours ago, MarkHurst said:

The KAP140 has its own alert functionality, which is what the Collins one is slaved to. It's slaved both ways, so you can preselect the altitude on the upper dial too if you want. The alert light isn't implemented, though. I suppose you could have two independent alerters, but it doesn't seem to make much sense.

 

But does changing the altitude selection in the KAP140 drive the Collins PRE-80 to change the altitude shown in the display window? I wouldn't think so; I believe that window is only driven by the selector knob on the PRE-80 unit.

 

As far as I recall, the PRE-80's cannot be actuated by any integrated avionics systems, so changing the altitude selector on the KAP140 shouldn't drive the altitude window to change in the Collins unit.

[MarkHurst 173]

9 hours ago, amahran said:

 

But does changing the altitude selection in the KAP140 drive the Collins PRE-80 to change the altitude shown in the display window? I wouldn't think so; I believe that window is only driven by the selector knob on the PRE-80 unit.

 

As far as I recall, the PRE-80's cannot be actuated by any integrated avionics systems, so changing the altitude selector on the KAP140 shouldn't drive the altitude window to change in the Collins unit.

 

Yes, it does. No point trying to make sense of it, this is a fictional mashup.