I made a contract with Atlanta Icelandic in 2003... the Icelanders gave me a JAR ATPL Icelandic validation with a... FAA ATPL (747 captain), not a single written exam, just a simulator check. So, TC or FAA, if you have plenty of time and experience, and thery want you or need you... is easy.
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They probably have a minimum - as you say 5000 hrs and ... whatever PIC time on type. I had well above these figures. So to my opinion, I would not get a headache about such validations or other licences.
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Ever since I started flying airlines (FAA ticket) in 1969... I had contracts in numerous places in the world, the FAA credentials were always accepted and validations were issued for other airlines or aircraft registries... Flown many airline contracts in Europe... Denmark, Luxembourg, Belgium, Iceland... in Asia, or Africa, or South America... Never was my concern. You want me, here is my licence. You do not validate FAA...? well, then you do not need me - Good bye...
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Happy contrails