The ProLine 21 Radio System will include dual Com's, Nav's, Marker Beacons, Glideslope's, ADF's, DME's, TXP's and Radio Tuning Units.
Upgrading the radios in your aircraft will prepare you for future changes in communications procedures with ATC, as well as bringing increased dispatch reliability.
The RTU-4220's provide the HSI function that will display magnetic or true heading, VOR/ILS selected course and deviation and glideslope deviation. The active COM, NAV and ATC frequencies/codes are displayed and can be adjusted on this page. The existing UNS-1Esp FMS will tune the blind channels of the newly installed Collins NAV-4000 DME. The UNS-1Esp is not capable of tuning the COM's, NAV's or ADF.