NAV and PIS lights - steady or blinking?
 

I assume that in civilian and military aviation, position and navigation lights will be switched to steady or blinking depending on time of day - but when is used what light mode? Blinking by night, steady by day?

And is it correct that in foggy conditions or in clouds outside lights and nav and pos lights sometimes get switched off, because the lights can blind the pilot, maybe? What about landing lights on ILS approach in heavy fog?

Generally speaking strobe/flashing lights are turned on when entering an active runway, and turned off after exiting an active runway. They're on at all times in between. They can even be turned on earlier, but generally aren't to avoid blinding other pilots while taxiing. Same for landing lights, which are kept on when flying between ground and 10,000ft altitude. For foggy conditions, these lights all have to be on. In poor visibility, additional turnoff lights (pointing to the side of the aircraft) are also generally turned on.

Steady nav lights are kept on at all times otherwise, and the rotating beacon is kept on any time that the engines are operating.

I don't believe they would be turned off at any point, especially in poor visibility, since their role is to alert nearby aircraft. That's why they're so bright in the first place.

The red and green position lights in some planes offer the option to run steady or blinkling. For example in the A-10 as well, but also in some civilian aircraft modules I have a switch for that option.

??

Red beacon, blinkling, gets turned on short before starting the engines.

White beacon blinkling, when entering the runway. However, I have contradicting info about these being switched of in fog, else they could blind the pilot, the fog serves like a reflecting wall and actually prevent the pilot from seeing lights from other planes himself. I had that in two airliner modules, I think even noticed on a small plate on the panel.