Part-66 Exam Format: Questions, Timing and the 75% Pass Mark

How many questions are in Part-66 exams, how long do you get, and what do you need to pass? This guide sets out the Part-66 exam format in one place: the question style, timing, the 75% pass mark and how many correct answers that means for each paper size, the absence of negative marking, partial exams, essays and what you may take into the room. Where EASA and UK CAA rules differ, both are shown.

Part-66 Prep is an independent study aid, not an authority or exam provider. The rules summarised here are in Appendix II to Part-66 (the basic examination standard). For EASA licences that is Regulation (EU) No 1321/2014, with Appendix II replaced by Regulation (EU) 2023/989 from 12 June 2024. For UK licences it is the retained UK Part-66 on legislation.gov.uk. The wider exam rules hub is Part-66 exams.

The Part-66 exam format in brief

Rule	EASA	UK CAA
Question type	Multiple choice	Multiple choice
Options per question	3, one correct	3, one correct
Time	Nominal 75 seconds per question	Nominal 75 seconds per question
Pass mark	75% per module or sub-module	75% per module or sub-module
Negative marking	None	None
Essays	Module 7 only (2)	Modules 7 (2), 9 (1), 10 (1)
Essay time	20 minutes each	20 minutes each
Partial exams	Over 90 min: up to 2; over 180 min: up to 3	Only B2 Module 13, into 2

The core format is identical in both systems. What differs is the number of questions on some papers, the essays and the splitting rule. The EASA vs UK CAA guide covers every difference.

How the questions are written

Appendix II sets out how examination questions must be built. In our own words, the main points are:

1. Every module is examined by multiple choice, with essays only where the standard requires them.
2. Each question has three possible answers, and only one is correct. Banks that use four options do not match the real exam.
3. The wrong answers must be believable. They should look equally plausible to someone who does not know the subject, so you cannot pass by spotting silly options.
4. In calculation questions, wrong answers come from procedural errors, such as applying a correction in the wrong direction or converting a unit incorrectly. They are not random numbers.
5. Questions are kept secure. Authorities and Part-147 organisations do not publish their questions, and candidates are not given them after the exam.

Point 4 is the one that changes how you should study. If the three options for a fuel quantity question are 1,080, 1,920 and 840 litres, two of them are the results of common mistakes. Practising with properly built distractors teaches you to recognise your own errors. The past papers guide explains why we do not use real exam questions and why no one can legitimately offer them.

Exam tip: Before choosing an answer to a calculation, ask which mistake would produce each of the other two options. If you can explain both, you can be confident in the third.

Timing: 75 seconds a question

The time for each paper comes straight from the number of questions multiplied by 75 seconds. So:

• 16 questions: 20 minutes
• 32 questions: 40 minutes
• 52 questions: 65 minutes
• 80 questions: 100 minutes
• 140 questions: 175 minutes
• 188 questions: 235 minutes

The figure is a nominal average. You will answer definition questions in 20 seconds and spend two or three minutes on a calculation. What matters is the overall pace. A practical method:

1. Go through the paper answering everything you can answer quickly.
2. For anything that needs longer, pick your best guess, mark it and move on.
3. Use the time you saved to go back to the marked questions.
4. Never leave a question blank at the end.

Essays are timed separately at 20 minutes each, so Module 7 under both systems gets an extra 40 minutes, and UK Modules 9 and 10 an extra 20 minutes each.

The 75% pass mark: how many correct answers you need

Every paper size in Part-66 is a multiple of four, so 75% always comes to a whole number. This table shows the marks needed for the common sizes and which papers use them.

Questions	Correct answers needed	You can get wrong	Examples
16	12	4	Module 1 category A
20	15	5	Module 3 category A; Module 8 UK; Module 9 UK (plus essay)
24	18	6	Module 8 EASA; Module 3 B3
28	21	7	Module 9 EASA; Module 1 B3 UK
32	24	8	Module 1 B1, B2; Module 14 B2 EASA; Module 17A B1
40	30	10	Module 5 B1.1; Module 4 B2; Module 10 B1 and B2 UK
44	33	11	Module 10 B1 and B2 EASA
52	39	13	Modules 2 and 3 B1, B2
60	45	15	Module 6 B2; Module 7 B2; Module 15 A; Module 11C
72	54	18	Module 5 B2; Module 6 B1 UK
80	60	20	Module 6 B1 EASA; Module 7 B1
92	69	23	Module 15 B1.1, B1.3
100	75	25	Module 11B B1.2; Module 12 A
128	96	32	Module 12 B1.3
140	105	35	Module 11A B1.1
188	141	47	Module 13 B2 EASA

Key fact: On a 16-question paper, five wrong answers is a fail. Short papers leave very little room, which is why candidates who breeze through long modules sometimes fail Module 1 or Module 8.

Essays are marked against key points in a model answer. You pass an essay with 75% of the required key points and no significant error on any of them. If you fail only the multiple-choice part or only the essay part of a module, you retake only the part you failed. The Part-66 essay questions guide explains the marking in detail.

No negative marking

Neither system uses penalty marking. A wrong answer scores zero, exactly like a blank. The rational strategy is therefore simple: answer every question. If you can eliminate one of the three options, a guess between the remaining two gives you a 50% chance, which over several questions adds real marks.

Paper sizes per module

Paper sizes depend on the module and your category. Here are the foundation modules every B1 and B2 candidate sits, as an overview (questions per paper):

Module	B1 EASA	B1 UK	B2 EASA	B2 UK
1 Mathematics	32	32	32	32
2 Physics	52	52	52	52
3 Electrical fundamentals	52	52	52	52
4 Electronic fundamentals	20	20	40	40
5 Digital techniques	40	40 (B1.2: 20)	72	72
6 Materials and hardware	80	72	60	60
7 Maintenance practices	80 + 2 essays	80 + 2 essays	60 + 2 essays	60 + 2 essays
8 Basic aerodynamics	24	20	24	20
9 Human factors	28	20 + 1 essay	28	20 + 1 essay
10 Aviation legislation	44	40 + 1 essay	44	40 + 1 essay

The category-specific modules (11 to 17), category A and B3 have their own sizes. The Part-66 modules guide lists every paper for every category under both systems, and each module page, for example Module 1 questions, has the full table for that module.

Partial exams for long modules

Under EASA rules since June 2024 (Appendix II point 1.12), a module exam with more than 90 minutes allowed may be divided into two partial exams, and one with more than 180 minutes into three. Each partial exam must:

• cover complementary parts of the module and take a similar time
• contain a number of questions that is a multiple of four
• be passed at 75% on its own
• be taken at the same organisation and recorded on the same certificate of recognition

Papers that qualify include Module 6 and Module 7 for B1 (100 minutes), Module 11A, 11B, Module 12, Module 15 for B1 and Module 13 for B2 (235 minutes, so up to three parts). Whether a paper is actually split is up to the organisation running the exam.

UK Part-66 has no general rule of this kind. It only says that the B2 Module 13 exam may be split into two examinations.

Calculators and what you can take in

Appendix II does not say whether calculators are allowed; it is left to the exam provider.

• CAA exam venues: the CAA's aircraft maintenance licence examinations page lists the approved items as one clear plastic pen and one eraser-tipped pencil with a sharpener. Electronic devices, watches, pencil cases and notes are prohibited, and rough paper is supplied. Calculators are not on the approved list; the page tells you to check your confirmation email for items specific to each exam (as of October 2026).
• Part-147 organisations: each sets its own rules within its approval. Ask before you book.
• EASA member state authorities: check with the authority or exam centre.

Questions in Modules 1, 2 and 3 are written so they can be worked by hand. Prepare without a calculator unless your exam centre has told you in writing that one is allowed.

Common format mistakes on exam day

Most marks lost to the format, rather than to the subject, come from a handful of habits:

• Reading only the first option that looks right. With plausible distractors, the first reasonable-looking answer is often a near miss. Read all three before you choose.
• Missing a negative in the stem. Questions that ask which statement is not correct, or which item is not required, catch people who skim.
• Spending five minutes on one calculation. On a 32-question paper that is four questions' worth of time. Mark it, guess and return.
• Changing answers without a reason. Change an answer only if you have spotted a specific error, not because it feels too easy.
• Ignoring units in the options. If two options have the same number but different units, the question is testing the conversion.
• Running out of time in long papers. In Module 11A or 13, check your pace at each quarter: about 35 questions per 44 minutes.

Exam tip: When you practise, sit at least some papers under the exact real conditions: a timer, no notes, no phone and rough paper only. The format itself becomes familiar, and that removes a surprising amount of exam-day stress.

Attempts and resits in one paragraph

If you fail, you must wait 90 days before retaking the module, or 30 days if a Part-147 organisation gives you a retraining course tailored to the subjects you failed. Under EASA rules you may make at most three attempts at a module in any 12-month period. Under UK rules you get three consecutive attempts, then a one-year wait before the next set of three. Before each exam you confirm in writing how many attempts you have made. The resit rules guide works through examples.

How our practice papers match the format

Every paper on Part-66 Prep follows the format above: three options, one correct, 75 seconds per question, a 75% pass line and no negative marking. On the start screen you choose EASA or UK CAA rules and the paper takes that system's size and time. Questions are spread over the sub-modules in line with EASA's acceptable means of compliance, and calculation questions get new numbers from templates, with wrong options built from procedural errors.

You can try it free: the B1.1 diagnostic gives you 20 questions across the category, and full paper 1 is free for every module, for example Module 1 for B1.1 or Module 8 for B2, where the EASA and UK sizes differ. Our free exam guides, EASA module exams and UK CAA module exams, summarise the rules for each system.

Your study plan

1. Decide whether you are sitting under EASA or UK CAA rules, and note the size of each paper for your category.
2. Take the free B1.1 diagnostic or the diagnostic for your category.
3. Sit paper 1 of your first module under timed conditions, at the real size, and practise the mark-and-move-on method.
4. Practise without a calculator for Modules 1 to 3.
5. Book when you score 85% or more on three different papers, leaving margin above the 75% line.