or have completed certain criteria. (no. of sectors and approaches)
Not true I'm afraid. Not under JAR anyway, which I assume is what we are talking about here since you mention CAAFU examiners.
Similar applies to class ratings. 2 years for SEP 1 year for MEP. Either have the experience to be signed off or short revalidation test!
Under JAR rules MEP can only be renewed/revalidated by test, not by experience.
However if you leave this longer than 5 (or is it 7) years, you will need to meet a CAAFU examiner again!
Almost right. If you let you IR expire for 5 or more years you have effectively lost it and need to do your initial IR test again with CAAFU. If you let it expire for 7 years you've also lost your ATPL gound exam credits.
So , for instance if you did an IR in ,say Jul 2002 and miraculously got a job, does this make the IR valid but not current?
Correct, it will be valid until Jul 2008 (1 year + 5 years), but only current until Jul 2003.
For completeness:
JAR-FCL 1.250 - Type Rating, Multi Pilot - Conditions
(a) Pre-requisite for training: An applicant for the first type rating for a multi -pilot aeroplane type shall:
(1) have at least 100 hours as PIC of aeroplanes;
(2) have a valid multi-engine instrument rating (A).
(b) Training for additional multi-pilot type ratings require a valid multi-engine instrument rating.
Cheers