Chance wrote:

As far as I know, when they do the "downed jet" escape drill, all
they're taught is how to escape the cockpit (partially or fully
submerged), and how to use the survival gear (inflatable vests, beacons,
survival rafts and so forth). 

So I guess that if they stay afloat long enough till help arrives, the
trainning is a success?

Many pilots during the Second World War and Korea couldn't swim either.

But do they know on how to float?