[Nowhere Man]

I thought the 121.5 mhz has been phased out in favor of the 406 mhz.

Not yet. In the year 2009, IIRC.

I haven't heard about 121.5 Mc being phased out but I know the 500 kc (600 meters) maritime distress frequency isn't in use anymore. Will they have to fit aircraft with gear that runs on 406 Mc?

[Chemist_Geek]

Well, the SARSATs won't be monitoring 121.5 after 2009 so ELTs and EPIRBs will have to be 406 MHz models, yes.

I believe that 121.5 (and 243.0) will remain as voice emergency frequencies.

As far as 500 kHz goes, yes, they stopped guarding that frequency a while ago. I believe that GMDSS still requires a watch on 2182 kHz, but I could be wrong - I know less about maritime radio than aeronautical.