GinoPino,
The UK CAA only included the English Language Proficiency on licences from March 2008, as per the ICAO requirements.
From this date, any person having been trained and examined in the UK or at a UK Approved FTO and subsequently issued with a UK issued JAR FCL licence has been assumed to be English Proficient to ICAO Level 4.
I would suggest you ask the UK CAA for an updated licence containing the necessary endorsement in Section XIII.
If this is stil not enough for the Turkish CAA you will need to undergo a Test of English for Aviation. This can be done in most countries and most certainly in Turkey. The most common tests are the Mayflower College Test of English for Aviation and the Melbourne University RMIT English Language Test for Aviation (RELTA) - you would have to ask the Turkish CAA which tests they accept as not all NAAs accept all tests.
You could find out more information here:
ICAO Aviation English courses and testing for pilots and air traffic controllers
Home > Aviation English Test > RMIT English Language Test for Aviation
Hope this helps.
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