correct as is WPT and TCN Descent Guidance Different Distances

[Frederf]

Not sure if it should be the same for both modes but currently TCN and WPT descent guidance is giving different distances with TCN having the steeper approach. In example track waypoint and TCN are colocated. WPT guidance is 30nm while TCN guidance is 24nm.

F18WPTTCNDescent.trk

[TimRobertsen]

In the Persian map, this number puts you at point of about 5900 feet MSL above the tacan.

In the Caucasus map, this number puts you at point about 6600 feet MSL above the tacan.

 

In both maps, this is regardless of the tacan’s elevation, and regardless of whether it is a carrier-tacan and airfield-tacan.

[Frederf]

Interesting. That would explain the closer distances. TACAN position is defined inside the airplane data so it knows the station elevation. That ~6kft would be an intentional feature. What I don't understand is why TACAN would have the extra height at end of descent and waypoint would not.