NeoFit
Right you are, any com from 447 would be memory only. The RMP3 inop was not an operational factor? How do we know this? two of three audio sort can definitely play a role. If 121.5 was needed under great pressure, and pilot needed a switch, the RMP inop could have been just one more thing to have gone wrong. Strikes me that MEL with two of three is a smidgeon lax?
bear