Stefan wrote in message ...

BTW: I always read the term CFI (certificated flight instructor). This
rises the question: Is there such a thing as an uncertificated flight
instructor?

Yes. You can receive instruction from military instructors in some
cases that are not CFIs (not certified as instructors by the FAA). You
can also be a CGI (ground instructor). The main reason we call it a
CFI is because that is what the FAA prints on the ticket, "Certified
Flight Instructor". Back in the pre 1970's days people just had
"Flight Instructor" as a rating on the pilot's ticket. Nowadays a CFI
is a different ticket, different piece of paper in your pocket from
your pilot's cert.

-Robert, CFI