B1.E and Module 18: the licence for electric aeroplanes

Electric aeroplanes are no longer a future topic for the Part-66 licence. Commission Implementing Regulation (EU) 2025/111 added a fifth B1 subcategory, B1.E, and a new basic knowledge module, Module 18 Electric Power Plant. Both apply from 13 February 2026. This guide sets out what changed, which modules a B1.E candidate sits, and what happens to engineers who already hold a B1 licence.

What B1.E covers

Point 66.A.3 now lists B1.E alongside B1.1 to B1.4 as aeroplanes with electric power plant and MTOM below 5 700 kg. Like the other B1 subcategories, it is a mechanical licence: structure, power plant and mechanical and electrical systems, with the avionics work that only needs simple tests. The difference is the power plant: batteries or fuel cells, power electronics and electric motors instead of a piston or turbine engine.

Electric aeroplanes of 5 700 kg and above are not covered by B1.E. For aircraft that do not fit any subcategory, the Agency names the applicable licence (sub)category in the aircraft type's operational suitability data.

Which modules a B1.E candidate sits

The module matrix in Appendix I gives B1.E the ten common modules, Module 11 (Aeroplane Aerodynamics, Structures and Systems), Module 17 (Propeller) and the new Module 18. There is no gas turbine or piston engine module on this path.

Module 11 for B1.E is the same length as for B1.2 (piston aeroplanes), not the longer B1.1 turbine paper. As with every module, the pass mark is 75% and there is no negative marking.

What Module 18 covers

Module 18 is examined at knowledge level 3 throughout, the most detailed level. Its submodules in Appendix I are:

• 18.1 Fundamentals
• 18.2 Engine performance
• 18.3 Engine construction
• 18.4 Electric energy system: batteries, fuel cells, power distribution and electronic engine control
• 18.5 Engine indication systems
• 18.6 Power plant installation
• 18.7 Engine monitoring and ground operation
• 18.8 Engine storage and preservation

Much of the groundwork sits in modules you take anyway. Batteries, DC and AC theory, motors and generators are in Module 3, semiconductors in Module 4, and electrostatic-sensitive devices and data buses in Module 5. A solid pass in those three makes Module 18 far more manageable.

Experience needed

Point 66.A.30 puts B1.E in the same group as category A, B1.2, B1.4 and B3: three years of practical maintenance experience on operating aircraft with no previous technical training, two years after relevant skilled-worker training, or one year after an approved Part-147 basic training course. At least one year of it has to be recent, on the subcategory you are applying for.

If you already hold B1.1 or B1.2

Article 5(8) gives a transition period. Until 13 February 2028, an aeroplane with electric power plant and MTOM below 5 700 kg may be endorsed on a B1.1 or B1.2 licence when all of these are met:

• you have at least 6 months of maintenance experience on aircraft covered by your licence (sub)category within the last 24 months;
• the electric aeroplane is not the first aeroplane endorsed for that (sub)category;
• you have completed type training under Appendix III, a directly approved type training (66.B.130), or the procedure in 66.A.45(da).

After that date, the regular route applies: the B1.E subcategory with Module 18 on your licence.

What changed for B2

The same regulation widened Module 14 (Propulsion) for B2 and B2L: submodule 14.1 now includes electric and hybrid power plants and their auxiliary systems, and engine control. Avionics engineers therefore meet electric propulsion too, from the indication and control side.