aircraft skin or the skin of an aircraft float if the work requires the use of a support, jig or fixture;
aircraft skin that is subject to pressurisation loads if the damage to the skin measures more than 15 cm (6 in.) in any direction;
a load-bearing part of a control system, including a control column, pedal, shaft, quadrant, bell crank, torque tube, control horn and forged or cast bracket, but excluding:
the swaging of a repair splice or cable fitting; and
the replacement of a push-pull tube end fitting that is attached by riveting;
any other structure not listed in point (a) that a manufacturer has identified as primary structure in their maintenance manual, structural repair manual or instructions for continuing airworthiness;
dismantling and subsequent reassembling of a piston engine other than:
to obtain access to the piston/cylinder assemblies; or
to remove the rear accessory cover to inspect and/or replace oil pump assemblies, where such work does not involve the removal and refitment of internal gears;
dismantling and subsequent reassembling of reduction gears;
welding and brazing of joints, other-than-minor weld repairs to exhaust units carried out by a suitably approved or authorised welder but excluding component replacement;
the disturbing of individual parts of units which are supplied as bench-tested units except for the replacement or adjustment of items normally replaceable or adjustable in service;
the balancing of a propeller, except:
for the certification of static balancing where required by the maintenance manual; and
dynamic balancing on installed propellers using electronic balancing equipment where permitted by the maintenance manual or other approved airworthiness data;
any additional task that requires:
specialised tooling, equipment or facilities; or
significant coordination procedures because of the extensive duration of the tasks and the involvement of several persons.