ASRS 2027067

Reporter 1

During the approach, flight crew was actively configuring the aircraft to Flaps 30 and reducing speed to achieve the stable approach criteria by 1000 ft. AGL. However, in the process of introducing our final flaps of 30 degrees, the aircraft made RA call of "One thousand.” However, we looked at our radio altimeter and it read 1200-1300. We confirmed all three barometric altimeters read approximately 1730 MSL. After a brief discussion of a go-around, Captain determined it was safe to introduce flaps 30 at that time 1100-1200 AGL and continue the final items of the landing checklist below 1000 ft. AGL. We later discussed the possibility the Radio Altimeter was experiencing interference. The remainder of the approach was safely flown to a completed landing. Cause- We anticipated the morning low level cloud layer to lift prior to conducting the approach to 36R at CLT. However, the clouds did not lift and the First Officer, with prior discussion, relinquished the flight controls to the Captain on radar downwind. The reason for the exchange was so the Captain could fly the aircraft using CAT III criteria to ensure our arrival into CLT. We later discussed possible Radio Altimeter interference as causal on our delay to call our approach stable just under 1000 ft. AGL. Suggestions- Control Radio Altimeter spectrum interference in the vicinity of CLT airport.

Reporter 2

During the approach, flight crew was actively configuring the aircraft to Flaps 30 and reducing speed to achieve the stable approach criteria by 1000 ft. above ground. However, in the process of introducing our final flaps of 30 degrees, the aircraft made the "One thousand," call. However, we looked at our radio altimeter and it read 1200-1300. After a brief discussion of a go-around, Captain determined it was safe to introduce flaps 30 at that time 1100-1200 RA and continue the final items of the landing checklist below 1000 ft. RA. Cause- We anticipated the morning low level cloud layer to lift prior to conducting the approach to 36R at CLT. However, the clouds did not lift and the First Officer, with prior discussion, relinquished the flight controls to the Captain prior to being vectored onto the final approach course. The reason for the exchange was so the pilot flying could execute a CAT III landing to ensure our arrival into CLT. Suggestions- The event could have been mitigated with a discussion and response to the task before entering the final phases of the descent/approach.