CH-47 and carrier group

Set the TACAN freq on the TACAN panel, then change your HSI Nav mode to TCN (button right under the HSI)

Only static Carriers have TACAN frequencies, more info here:
https://docs.miltechsimulations.com/v/supercarrier-pro/supercarriers/approach-and-landing-equipment-and-operations/instrument-approach-and-communications-equipment

OK thanks looks like it is not on the UK carrier