CDI(course deviation indicator) does not work when using DF

[Northwind]

CDI(course deviation indicator) does not work when using DF, it works when using TACAN.

CDI no deviation when using DF.

 

 

 

 

stable version 2.5.5.39384

Edited December 4, 2019 by Northwind

[tom_19d]

This is normal behavior. DF equipment can only provide a bearing to (or from) a station. The signal DF equipment is homing on (a downed pilot’s beeper for example) is only transmitting audio, not navigation information like a TACAN.

[Northwind]

CDI only need bearing.It should work.

[randomTOTEN]

TACAN (Like VOR/RSBN) is a "directional signal." This means the signal contains direction information (signal changes as your bearing from the station changes). The onboard TACAN receiver interprets this signal and displays the calculated "Radial" on both the CDI and the bearing pointer needle.

 

 

CDI needs received Radial, not bearing.

[tom_19d]

TACAN (Like VOR/RSBN) is a "directional signal." This means the signal contains direction information (signal changes as your bearing from the station changes). The onboard TACAN receiver interprets this signal and displays the calculated "Radial" on both the CDI and the bearing pointer needle.

 

Well said.

 

From 1F-5E-1 (Change 9)

"TACAN - HSI steering and navigation indications provided by TACAN

DF - bearing pointer points to UHF station selected on UHF radio"

[Frederf]

CDI only need bearing.It should work.

I know of no instance in all of aviation simple radio homing where CDI would function. NDBs, LOMs, comms DF, HFDF, etc. are bearing only.

 

With ILS, VOR, TACAN, etc. the CDI isn't working on difference between bearing and selected course but an independent channel of difference information.

[Northwind]

Looks like I'm mistaken how CDI works.

Thank you guys.