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3.1 Theoretical element

Annex III (Part-66) · Regulation (EU) No 1321/2014 · EAR revision 2 Sep 2025

IRImplementing rule

3.1Theoretical element

(a)Objective: On completion of a theoretical training course the student shall be able to demonstrate, to the levels identified in the Appendix III syllabus, the detailed theoretical knowledge of the aircraft’s applicable systems, structure, operations, maintenance, repair, and troubleshooting in accordance with maintenance data. The student shall be able to demonstrate the use of manuals and approved procedures, including the knowledge of relevant inspections and limitations.

(b)Level of training: Training levels are those levels defined in point 2 above. After the first type course for category C certifying staff all subsequent courses need only be to level 1. During a level 3 theoretical training, level 1 and 2 training material may be used to teach the full scope of the chapter if required. However, during the training the majority of the course material and training time shall be at the higher level.

(c)Duration: The theoretical training minimum tuition hours are contained in the following table:

CategoryHours
Aeroplanes (*1) with a maximum take-off mass above 30 000 kg:
B1.1150
B1.2120
B2100
C30
Aeroplanes (*1) with a maximum take-off mass equal to or less than 30 000 kg and above 5 700 kg:
B1.1120
B1.2100
B2100
C25
Aeroplanes (*1) with a maximum take-off mass of 5 700 kg and below (*2)
B1.180
B1.260
B1.E60
B260
C15
Helicopters (*1) (*3)
B1.3120
B1.4100
B2100
C25
Aeroplanes and helicopters not mentioned above and non-conventional aircraft
B1, B2 and COSD

(*1) Aeroplane with piston or turbine engine or electric power plant or helicopter with piston or turbine engine. (*2) For non-pressurised aeroplanes below 2 000 kg MTOM with piston-engine or electric power plant, the minimum duration can be reduced by 50 %. (*3) For helicopters in Group 2 (as defined in point 66.A.5), the minimum duration can be reduced by 30 %. In the table above, ‘OSD’ means as defined in the operational suitability data established in accordance with Regulation (EU) No 748/2012, taking into consideration a report from the applicant for, or holder of, the aircraft type certificate that contains an assessment of the required theoretical elements of knowledge of the aircraft, considering the applicable licence (sub)category on which the aircraft type would be permitted for endorsement in accordance with point 66.A.3. For the purpose of the table above, a tuition hour means 60 minutes of teaching and excludes any breaks, examination, revision, preparation and aircraft visit. These hours apply only to theoretical courses for complete aircraft/ engine combinations according to the type rating as defined by the Agency.

(d)Justification of course duration: Training courses carried out in a maintenance training organisation approved in accordance with Annex IV (Part-147) and courses directly approved by the competent authority shall justify their hour duration and the coverage of the full syllabus by a training needs analysis based on: the design of the aircraft type, its maintenance needs and the types of operation, detailed analysis of applicable chapters — see contents table in point 3.1(e) below, detailed competency analysis showing that the objectives as stated in point 3.1(a) above are fully met. Where the training needs analysis shows that more hours are needed, course lengths shall be longer than the minimum specified in the table. Similarly, tuition hours of differences courses or other training course combinations (such as combined B1/B2 courses), and in cases of theoretical type training courses below the figures given in point 3.1(c) above, these shall be justified to the competent authority by the training needs analysis as described above. In addition, the course must describe and justify the following: The minimum physical and/or virtual classroom attendance required of the trainee, in order to meet the objectives of the course. The maximum number of hours of physical and/or virtual classroom training per day, taking into account pedagogical and human factors principles. If the minimum attendance required is not met, the certificate of recognition shall not be issued. Additional training may be provided by the training organisation in order to meet the minimum attendance time.

(e)Content: As a minimum, the elements in the Syllabus below that are specific to the aircraft type shall be covered. Additional elements introduced due to type variations, technological changes, etc. shall also be included. The training syllabus shall be focused on mechanical and electrical aspects for B1 personnel, and electrical and avionic aspects for B2. If it exists, the minimum syllabus of the operational suitability data (OSD), established in accordance with Regulation (EU) No 748/2012, shall be included.

Level ChaptersAeroplanes turbineAeroplanes pistonAeroplanes with electric power plantHelicopter turbineHelicopter pistonAvionics
Licence categoryB1.1CB1.2CB1.ECB1.3CB1.4CB2
Introduction module:
05 Time limits/maintenance checks11111111111
06 Dimensions/areas (MTOM, etc.)11111111111
07 Lifting and Shoring11111111111
08 Levelling and weighing11111111111
09 Towing and taxiing11111111111
10 Parking/mooring, storing and return to Service11111111111
11 Placards and markings11111111111
12 Servicing11111111111
20 Standard practices – only type particular11111111111
Helicopter
18 Vibration and noise analysis (blade tracking)——————3131—
60 Standard practices rotor——————3131—
62 Rotors——————31311
62A Rotors – monitoring and indicating——————31313
63 Rotor drives——————31311
63A Rotor drives – monitoring and indicating——————31313
64 Tail rotor——————31311
64A Tail rotor – monitoring and indicating——————31313
65 Tail rotor drive——————31311
65A Tail rotor drive – monitoring and indicating——————31313
66 Folding blades/pylon——————3131—
67 Rotors flight control——————3131—
53 Airframe structure (helicopter)——————3131—
25 Emergency flotation equipment——————31311
Airframe structures
51 Standard practices and structures (damage classification, assessment and repair)313131————1
53 Fuselage313131————1
54 Nacelles/pylons313131————1
55 Stabilisers313131————1
56 Windows313131————1
57 Wings313131————1
52 Doors313131————1
Zonal and station identification systems11111111111
Airframe systems
21 Air conditioning31313131313
21A Air supply31313131312
21B Pressurisation31313131313
21C Safety and warning devices31313131313
22 Autoflight21212121213
23 Communications21212121213
24 Electrical power31313131313
25 Equipment and furnishings31313131311
25A Electronic equipment including emergency equipment11111111113
26 Fire protection31313131313
27 Flight controls31313131312
27A Sys. operation: electrical/fly-by-wire31——3131——3
28 Fuel systems3131——31312
28A Fuel systems – monitoring and indicating3131——31313
29 Hydraulic power31313131312
29A Hydraulic power – monitoring and indicating31313131313
30 Ice and rain protection31313131313
31 Indicating/recording systems31313131313
31A Instrument systems31313131313
32 Landing gear31313131312
32A Landing gear – monitoring and indicating31313131313
33 Lights31313131313
34 Navigation21212121213
35 Oxygen313131————2
36 Pneumatic31313131312
36A Pneumatic – monitoring and indicating31313131313
37 Vacuum31313131312
38 Water/waste313131————2
41 Water ballast313131————1
42 Integrated modular avionics21212121213
44 Cabin systems21212121213
45 On-board maintenance system (or covered in 31)31313131——3
46 Information systems21212121213
47 Nitrogen generation system3131——————2
50 Cargo and accessory compartments31313131311
55/57 Flight control surfaces (All)313131————1
Turbine engine
70 Standard practices – engines31————31——1
70A Constructional arrangement and operation (installation inlet, compressors, combustion section, turbine section, bearings and seals, lubrication systems)31————31——1
70B Engine performance31————31——1
71 Power plant31————31——1
72 Engine turbine/turbo prop/ducted fan/unducted fan31————31——1
73 Engine fuel and control31————31——1
75 Air31————31——1
76 Engine controls31————31——1
78 Exhaust31————31——1
79 Oil31————31——1
80 Starting31————31——1
82 Water injections31————31——1
83 Accessory gear boxes31————31——1
84 Propulsion augmentation31————31——1
73A FADEC31————31——3
74 Ignition31————31——3
77 Engine indicating systems31————31——3
49 Auxiliary power units (APUs)31————————2
Piston engine
70 Standard practices – engines——31————311
70A Constructional arrangement and operation (installation, carburettors, fuel injection systems, induction, exhaust and cooling systems, supercharging/turbocharging, lubrication systems)——31————311
70B Engine performance——31————311
71 Power plant——31————311
73 Engine fuel and control——31————311
76 Engine control——31————311
79 Oil——31————311
80 Starting——31————311
81 Turbines——31————311
82 Water injections——31————311
83 Accessory gear boxes——31————311
84 Propulsion augmentation——31————311
73A FADEC——31————313
74 Ignition——31————313
77 Engine indication systems——31————313
Electric power plant
Electric engines————31————3
Fuel cell and related systems————31————3
Batteries————31————3
Auxiliary systems to the electric power plant————31————3
Propellers
60A Standard practices – propeller313131————1
61 Propellers/propulsion313131————1
61A Propeller construction313131—————
61B Propeller pitch control313131—————
61C Propeller synchronising313131————1
61D Propeller electronic control212121————3
61E Propeller ice protection313131—————
61F Propeller maintenance313131————1
Special chapters for aeroplanes with a power plant other than piston/turbine/electric and other than piston/turbine helicoptersDefinition of special chapters of the theoretical element of the aircraft type training is available in the OSD of the aircraft, established in accordance with Regulation (EU) No 748/2012. For these aircraft, EASA can also consider as “not required” some of the chapters contained in the above table.
Special chapters for non-conventional aircraftDefinition of special chapters of the theoretical element of the aircraft type training is available in the OSD of the aircraft, established in accordance with Regulation (EU) No 748/2012. For these aircraft, EASA can also consider as “not required” some of the chapters contained in the above table.

IR · 3.1 — Regulation (EU) No 1321/2014 · Continuing Airworthiness Easy Access Rules · EAR revision 2 Sep 2025

All rules in APPENDICES TO ANNEX III (Part-66)

Consolidated from the EASA Easy Access Rules (revision 2 Sep 2025, extracted 17 Aug 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.

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