AMC1 ORO.FC.125 Differences training and familiarisation training
CAA ORS9 Decision No. 1
(a) Differences training requires additional knowledge and training on the aircraft or an appropriate training device. It should be carried out:
(1) when introducing a significant change of equipment and/or procedures on types or variants currently operated; and
(2) in the case of aeroplanes, when operating another variant of an aeroplane of the same type or another type of the same class currently operated; or
(3) in the case of helicopters, when operating a variant of a helicopter currently operated.
(b) Familiarisation training requires only the acquisition of additional knowledge. It should be carried out when:
(1) operating another helicopter or aeroplane of the same type; or
(2) when introducing a significant change of equipment and/or procedures on types or variants currently operated.