When pilots quote how many hours they have logged, is this a personal log
that is kept, or is every hour you fly entered into a national registry and
formally kept?

It is a personal log; no national registry is kept. It is required that
any flight time that you use towards currency requirements and ratings
be logged appropriately. It is not required that all time be logged,
though as a matter of practice most pilots probably log it all. There
are rules about how the log is kept (for example, the flight conditions
(day/night, instrument, simulated instrument), the administrative
conditions ("pilot in command, second in command, single engine/multi
engine) and other things. It's basically fairly simple, although
certain nuances of the rules keep Usenet participants busy posting when
they should be flying.

Jose
--
The monkey turns the crank and thinks he's making the music.
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