Differences training is important
Once obtained, the privileges of particular class rating authorizes the holder to fly on the specific variant on which the skill test with EASA examiner has been successfully passed on. This applies basically for all class ratings - e.g. SEP(land), TMG, MEP(land) but also for the EASA typerating.
It is important to mention that Differences training is required for all variants and all EASA license holders. That means the differences training is mandatory for PPL(A), CPL(A), ATPL(A) and MPL(A) holders as required by FCL.710 and GM1 FCL.710. For LAPL(A) holders the differences training is required by FCL.135(b) and GM1 FCL.135(a). That means nobody is exempted from attending the differences training.
AMC2 ORA.ATO.125 also specifies further the differences training for type ratings. Where an aeroplane type rating also includes variants of the same aircraft type for which difference training is required, the initial training course should be directed towards a single variant. Additional training to operate other variants within the same type rating should be completed after successful completion of the initial type rating course. However, elements of this differences training may be undertaken at appropriate stages of the initial course, with the agreement of the competent authority.
Variants requiring Differences training ✈️
Aircraft within class ratings do not have associated OSD in accordance with Part-21. The ‘EASA type rating and licence endorsement lists — flight crew’ provide categories of class ratings — such as SEP, MEP, SET, etc.— and indicate aircraft which are considered as variants.
Aircraft within the same class rating which are separated by a horizontal line in the tables in "EASA type rating and licence endorsement lists — flight crew" require differences training, whereas those aircraft which are contained in the same cell require familiarisation when transitioning from one aircraft to another. As an example, a SEP (land) aeroplane with variable pitch propeller and a SEP (land) aeroplane with retractable undercarriage require differences training, whereas two different SEP (land) aeroplanes, both with cabin pressurisation require familiarisation.