Big picture in bad weather certain aircraft that relied on their radar altimeter to help guide them to the runway cannot do so at certain locations.

http://www.alpa.org/resources/aircraft-operations-radar-alti...

> When operating in U.S. airspace, the following operations requiring radio altimeter are prohibited in the presence of 5G C-Band wireless broadband interference

> Instrument Landing System (ILS) Instrument Approach Procedures (IAP) SA CAT I, SA CAT II, CAT II, and CAT III

Here is the S-ILS RWY 36 for DFW that requires SA CAT II. At the bottom you can see "RA 107/12" which means the airplane can fly down to 107' without seeing the runway. The 5G NOTAMS effect this approach.

https://resources.globalair.com/dtpp/globalair_06039I36LSAC2...

Here is the NOTAM for DFW affecting approaches.

> FDC 2/3758 (A0495/22) - IAP DALLAS-FORT WORTH INTL, DALLAS-FORT WORTH, TX. ILS RWY 17C (SA CAT I), AMDT 11B ... ILS RWY 17L (SA CAT I), AMDT 7 ... ILS RWY 18R (SA CAT I), AMDT 8A ... ILS RWY 35C (SA CAT I), AMDT 3 ... ILS RWY 35R (SA CAT I), AMDT 4B ... ILS RWY 13R (SA CAT I - II), AMDT 9B ... ILS RWY 17R (SA CAT I - II), AMDT 23D ... ILS RWY 18L (SA CAT I - II), AMDT 3 ... ILS RWY 31R (SA CAT I - II), AMDT 15 ... ILS RWY 17C (CAT II - III), AMDT 11B ... ILS RWY 17L (CAT II - III), AMDT 7 ... ILS RWY 18R (CAT II - III), AMDT 8A ... ILS RWY 35C (CAT II - III), AMDT 3 ... ILS RWY 35R (CAT II - III), AMDT 4B ... ILS RWY 36L (SA CAT II), AMDT 4 ... PROCEDURE NA EXC FOR ACFT USING APPROVED ALTERNATIVE METHODS OF COMPLIANCE DUE TO 5G C-BAND INTERFERENCE PLUS SEE AIRWORTHINESS DIRECTIVES 2021-23-12, 2021-23-13. 19 JAN 05:00 2022 UNTIL 19 JAN 05:04 2024 ESTIMATED. CREATED: 13 JAN 05:05 2022