From my POV (regional Dash8 FO in Oz)
Obviously, language differences in Australia aren't an issue.
By 'FREDA', I'm assuming you're talking about what we in Australia call 'CLEAROF' checks (Compass, Log, Engine, Altitude, Radio, Orientation (i.e. nav), Fuel). As others have said, we generally check the engine gauges as a habit every 15-20 min or so. We're not required to keep a nav log, but we are required to check our expected vs. actual time over waypoints as we pass them. In regional flying you get to know the radio frequencies and roughly where you get handed over to the next controller.
If we lost our magenta line (has happened to me) we still have other instruments to maintain our navigation. If we lose our GPS (or FMS) we still can still navigate with reference to land based aids (VOR and NDB) but would advise ATC of the fact, as our navigation tolerance would degrade.
Regarding checklists: We have 'Geographics', 'Normal checklists' 'Recall items' and 'Reference items'.
Geograhpics refers to the sequence of activities that each pilot performs at various stages of flight and on the ground. They generally follow an ergonomic flow and are memorised (you also develop a muscle memory for each one). At the completion of a sequence of Geographics there is usually a 'Normal checklist'. For our airline we use stand-up checklists on top of the glareshield. Any Normal checklist cannot be performed by memory.
We also have a QRH (Quick Reference Handbook) for abnormals and emergencies. The QRH contains a large number of checklists, depending on what has gone wrong. Some of the checklists are considered 'Recalls', some are 'Reference' and some have a mixture of both (Recall then reference).
As the name suggests, you must be able to perform the Recall items from memory. Reference items can be read from the checklist. Recall checklist items are considered to be the vital actions that must take place as soon as practical to ensure the best chance of safely continuing. In the Dash, there are around 15 of Recall checklists. Reference checklists, while still important, are not so urgent and there is time for the PM to get the QRH out, look up the problem, and then action the checklist.
To give some examples:
After both engines have started, the Captain and FO have their 'After start' geographics, where both pilots perform configuration changes to the aircraft (e.g. Flaps 5) as well as checking performance items (e.g. confirm that the Transponder is ON/ALT). On completion of the After start geographics, the After start checklist is read. This wont check every single thing that you've done during the geographics, but will confirm every vital action.
If, during flight, an engine shuts down, there will be Recall items required to be performed by the PM. In this case, the Recall items are there to secure the engine. After the Recall items are complete, the PF will ask the PM to perform the Engine fail/fire shutdown checklist from the QRH. The PM gets to the checklist and confirms that the Recall items have been done correctly and then continues on with the Reference items. In this case the reference items refer to considerations such as landing distance factors with one engine inoperative, fuel transfer, etc.
Even during sterile cockpits you'd have a pretty good idea if the other pilot became incapacitated. As the other posters mentioned, there is still activity and any change to the normal "ebb and flow" of activity is noticed pretty quickly. (Besides, it's not uncommon to continue normal conversations during the bulk of the sterile cockpit phase
)
Hope that helps.
P.S. These were great questions, btw, and I get the feeling you're putting yourself down when you're asking them. We were all low-hours PPL holders at one time.
