REGULATIONS which affect cross-crew qualification (CCQ) and mixed-fleet flying sometimes directly limit the number of commercial type-ratings a pilot is allowed to have on his licence, but in all cases specify the training necessary first to obtain the type ratings and then to maintain type-rating currency. The regulatory components are:
pilot's licence: once obtained, a licence to fly is permanent unless downgraded or withdrawn by the authorities for medical or competency reasons;
type-rating: an airline pilot's licence is useless unless it is endorsed with a type rating, which reflects the successful completion of authorised minimum systems-knowledge and flying-skills training on at least one aircraft type;
licence currency: currency is conditional upon the completion of a minimum amount of flying in a given calendar period, and a set amount of type-specific refresher training or line checking. When applied to more than one type, "recency" rules may apply to each aircraft type, specifying the maximum time, which may elapse since the pilot last flew that type without a required period of retraining;
common type-rating: some types are so similar in systems and flying characteristics that the authorities grant a common type-rating. Examples of large aircraft with a common type-rating include: Airbus Industrie's A319/A320/ A321 series, and its A310 and A300-600; Boeing's 737 series, and also its 757 and 767; and McDonnell Douglas' DC-9/MD-80 series. Training for a common type-rating consists of a full course, plus specified minimum line-operational experience on one of the types, then a "differences course" for the other(s), which does not normally need to be repeated. Cost of refresher training and checks are kept the same as that for a single type by "flip-flop" training, which alternates the pilots' training and checks periodically between the various types in the group;
cross-crew qualification (CCQ): the system of training a pilot to a full type-rating on one aircraft within a group of types which are ruled to be generically similar (but not similar enough for a common rating), then being able to gain full ratings on the other(s) with shortened courses;
mixed-fleet flying: airline operation which makes full use of CCQ by flying aircraft in an accepted group.
Source: Flight International
