radio talking
 

In your procedure, who is talking on the radio during non-normal conditions?

Manuals are generally silent on the matter, so a "mild" non-normal results in the standard roles for Pilot Not Flying (PNF) on the radio and Pilot Flying (PF), with both operating switches in their area of responsibility.

Commander can always direct otherwise, though, so in a "major" non-normal, where the commander becomes the PF either by direction or automatically, and with a requirement for faster action than directing radio comments through the PNF can achieve, I personally would physically fly the aircraft AND liaise with ATC through the radio, and direct the PNF to read & do the QNH.

As, for instance, occurred in the Hudson ditching.

ok!
we are actually automatically delegating the radio to the PF while the PM is running the non-normal checklists (no differences if the PF is Cpt or FO).

This is a process that probably will change and probably the PM will be responsible for the radio both in normal and non-normal situations, while the PF is riding the horse!
We agree with the fact that it is alway Cpt final call to delegate the radio in every scenario, but ...

We ran an evaluation about this issue some years ago and changed the SOP/ FOM after 3 months testing during sim training.

PNF/PF announces non-normal condition
PF orders: non-normal checklist (title of NNC) my controlls, my radio
PNF deals with checklist
When checks completed PNF confirms: End of checklist, my radio

This allows the captain also to decide about PF after malfunction is announced.

Worked charming. EU airline.