NVB9ALT
commented
1 year ago The overlay indicator uses KCAS, while the cockpit indicators use KIAS (which in GeoFS is equal to KTAS). The reason for this is that if I redefine KIAS to be KCAS, then non-instrument-related animations or effects that use KIAS will no longer work properly. Now that I think about it, though, I might add a UI button to toggle interior instruments to show either KIAS (i.e. KTAS) or KCAS.
Here's the difference in case you don't know:
- KTAS: your speed relative to the air, indicated in knots
- KIAS: your speed relative to the air, divided by the air density in atmospheres (I think, roughly). This means that if you maintain constant KTAS, your KIAS will decrease with altitude. The fun thing about this is that your stall speed in KIAS never changes - you will stall at (for example) 120 KIAS regardless of altitude, however, 120 kias at high altitude is a higher KTAS than at sea level. In GeoFS, however, KIAS is equal to KTAS.
- KCAS: KCAS is KIAS corrected for errors caused by the position of the pitot probe. In GeoFS with the Realism Pack, KCAS is accurately simulated for exterior instruments.
Finally, you might be interested to know that the "exterior instruments display KCAS" thing is more or less copy-and-pasted from AP++.
Somnambolist
Greetings!
Great add-on, really love it, thanks!! I noticed the following issue: (at least) on the Boeing 737, the indicator on the cockpit instrument shows a different airspeed than on the overlay instrument.
To make things even more mysterious: I noticed, when I spawn at the takeoff of a runway, the indicators are in sync, but the speed remains too low (in other words, the value in the overlay instrument remains true (which is too low for the type)). However, when I spawn in the air, there is the observed mismatch but the cockpit instrument displays the realistic value.
Not sure what's up there, maybe you can have a look?
Thanks and best regards!!