Pilot reported encountering possible 5G interference affecting the radio altimeter while on final to DFW.
Synopsis
Pilot reported encountering possible 5G interference affecting the radio altimeter while on final to DFW.
Narrative
Memo indicated that there might be a Thrust Reverser deployment issue as a result of RA (Radar Altimeter) interference because of 5G C-Band deployment. I was PM (Pilot Monitoring) and the FO (First Officer) was PF (Pilot Flying). Landing on 35R in DFW everything was normal throughout the approach. When in the final landing phase where the airplane uses the RA to call out 50; 40; 30; 20; 10 - we did not receive the 10 foot call. On landing the FO indicated that the thrust reversers would not deploy. I looked at the EICAS (Engine Indicating and Crew Alerting System) display and they were armed. I looked at the switches as well. I took the controls and tried myself and indeed they would not deploy. NO REV Icon was displayed on the EICAS. They behaved exactly as they do when not armed. We exited the runway and I noted that the [Spoiler System] message was still deployed which seemed odd; but upon stopping it went away. I retried the reversers to see if they would unlock and they did and did indicate REV on the EICAS display.I am unsure if 5G C-band is even turned on in the DFW area. So I cannot say for sure this was interference. However; talking to MX (Maintenance) Control when I called them; they said [cellular company] did have their C-band turned on in the DFW area.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.