All pilots are subject to flight reviews to check their skills and to maintain their privileges to fly.
BFR - Biennial Flight Review
For FAA pilot license holders, a BFR is required every 24 calendar months.
The flight review consists of at least 1 hour of ground instruction and 1 hour in-flight with a qualified flight instructor.
IPC - Instrument Proficiency Check
IPC is a flight review for pilots who hold a valid instrument rating but have not recently flown using instrument procedures.
It is a full review of knowledge and procedures needed to fly an aircraft on an instrument flight plan and fly under instrument meteorological conditions (IMC).
ICAO English Proficiency for Pilots
English Proficiency Test - Extension of Level 4 for JAR pilot license holders.