EASA Part-66 Category B1 Modules
The exact knowledge modules a Category B1 licence requires — with live practice-question counts for each.
12–13
Modules to pass
16,333+
Practice questions
75%
Exam pass mark
Module applicability per Commission Implementing Regulation (EU) 2023/989, Appendix I § 2. See the full applicability matrix.
What Category B1 covers
Category B1 (mechanical) permits release to service following maintenance on aircraft structure, powerplant and mechanical and electrical systems, plus work on avionic line-replaceable units requiring only simple tests. It is split by airframe and engine type into B1.1, B1.2, B1.3 and B1.4.
Modules common to every Category B1 sub-category
10 modules · tap any module to start practising
Then add your airframe & engine modules
The sub-category you certify decides which of these you also need.
The Category B1 exam
Module count by sub-category — B1.1: 13 modules, B1.2: 13 modules, B1.3: 12 modules, B1.4: 12 modules.
Each module is examined by multiple-choice questions with a 75% pass mark (Module 7 also carries an essay). The number of questions and the time allowed vary by module and category.
See the full exam structure for the per-module question count and time, and the experience requirements for Category B1.
Frequently asked questions
How many modules do I need for a B1 licence?
What is the difference between B1.1 and B1.2?
Practice Category B1 exam questions
16,333+ practice questions across every module you need, each with a worked explanation.
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