The RM-855 radio management unit (RMU) is a fully compatible replacement of the RM-850 with enhanced reliability and capability based on a liquid crystal display unit for additional functionality. The RM-855 RMU is the primary interface used to control the Primus® II radio system in the Primus 1000 and Primus 2000 flight decks.
- High frequency tuning, NAV Radio back up tuning, 3rd Com tuning
- Switch COM radios from voice to data mode (when equipped)
- option to show a navigation radio magnetic indicator and engine backup display on the RMU
- Upgrades are easier - software only
- Required for ADS-B Out mandate