Piston Engine EASA Part-66 — Module 16 Practice Questions

What Module 16 covers — in plain English

Module 16 of the EASA Part-66 syllabus covers the piston aeroplane engine end-to-end: the thermodynamic cycles that turn fuel into shaft power, the mechanical construction of crankcase, crankshaft, cylinders and valve gear, and the supporting systems — fuel, ignition, induction, exhaust, cooling, supercharging and lubrication. It is one of the more technical modules in the syllabus because nearly every section has both a theoretical side (cycle diagrams, mixture ratios, manifold pressure, compression ratio) and a hands-on side (magneto checks, carb heat application, oil pressure indications, ground run-up procedures). The current syllabus also adds a sub-section on alternative piston engine constructions — hybrid-electric concepts and power augmentation — reflecting where general aviation is heading.

The module is sat under the B1.2 (piston aeroplane), B1.4 (piston helicopter) and B3 licence routes, and by sub-categories A2 and A4. Turbine-only candidates (B1.1, B1.3, B2, B2L) do not sit Module 16 — they cover Module 17 (Propeller) and the turbine engine module instead. B1.2, B1.4 and B3 candidates work at knowledge level 2 across nearly all sub-sections, with section 16.12 (Engine Monitoring and Ground Operation) requiring the deeper knowledge level 3 for hands-on troubleshooting, parameter interpretation and run-up fault diagnosis. Section 16.13 (Storage and Preservation) is not required for category A candidates, and section 16.14 (Alternative Constructions) sits at knowledge level 1 for everyone.

Compared to the turbine module, Module 16 rewards candidates who have spent time around the engines themselves: many questions test whether you can connect a symptom (rough running, low oil pressure, magneto drop, high CHT) back to the underlying mechanism. Watch out in particular for definition questions on compression ratio, distinction questions on detonation versus pre-ignition, and envelope questions on carburettor icing — these recur in nearly every sitting and distractors are deliberately close to the correct answer. Lubrication and indication questions tend to reward candidates who can name the components in a typical wet-sump or dry-sump diagram and explain what each pressure or temperature gauge actually reads. Fuel-system questions split between traditional float-type carburettors and modern continuous-flow injection, with a small number of FADEC questions sitting at level 2 under section 16.4.3. The questions below show that style — short stems, three plausible answers, and a single principle the right answer hinges on. The full per-section knowledge-level breakdown and study order is on our Module 16 syllabus page.

These samples are drawn from our live Module 16 question bank of 500 questions. The full timed practice quiz draws 76 questions per attempt (or 52 for Cat A), scored against the official EASA 75 % pass mark, with weak-area tracking across attempts.