Couple of assorted questions for dim pilot.
After not having flown for 14 years, I've now gotten back into it and revalidated my license. However, even after rereading the theoretical stuff, there are some things I keep missing or don't understand. All very random, so best suited for simmered down couchies with broad knowledge.
1. Oxygen. In the US it's mandatory above 12500ft, whereas in Europe it seems to be 10.000ft. Is this European one a recommended altitude for oxygen, or a mandatory one?
2. Transponder. What exactly is the difference between a Mode C and a Mode S transponder?
3. Transponders abroad. Was it in the Netherlands that one could not fly without a Mode S transponder? Any other countries that have similar rules?
4. Weather. From when I read TAF's and METAR's, I can't find any references to the tops of the cloud bases, only the ceilings. Where do people get this info?
5. NOTAMs. Where do I find them for, let's say, international flight planning? And is there a way of plotting a route visually and then have all the relevant Notams that could affect pop up? If not, how do you sift through all of that to find relevant stuff pertaining to your track/route?
6a. Min altitude. Back in the days when I did it in Sweden it used to be 500ft AGL was the lowest altitude one could fly at except for approaches and takeoffs. I couldn't see any reference to that in my new PPL theory book. What's the minimum alt?
6b. Min altitude at airport. This question only relevant if min altitude is 500ft AGL (see above). At Lydd they won't let anyone take-off VFR when the cloud base is below 1000ft. Now, if the min altitude is 500ft AGL allowable, then why do they impose this? And is it up to each airport to set their own minima (not saying it would be prudent to takeoff in 500ft of cloud base, just wondering about the legalities)?
7. What to call them? When you approach, let's say, London TMA and call them up to get a clearance - how do you know what to call them? How do you know it's Control and not Radar, or Approach? All it says is London TMA or CTA or something on the map.
8. Permit To Fly. What's the difference between a permit to fly and C of A in practical terms? Can you fly abroad with a permit to fly aircraft (seem to remember that Jersey wouldn't allow PtF aircraft)?
9. Transponder settings. It seems like most instructors want you to put the transponder to STBY after checks, and then switch it to ALT before you leave earth. Why is that? Why can't one just leave it in ALT all the time?
Thanks.