100+ Free Module 15 Practice Questions
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Key Facts: Module 15 Exam
92 questions / 115 min
B1.1/B1.3 Module 15 Exam
EASA Part-66 examination standard
75%
Pass Mark per Module
EASA Part-66
~75 seconds
Time per Question
115 min / 92 questions
12 June 2024
Regulation (EU) 2023/989 Applicable
Commission Implementing Regulation (EU) 2023/989
22 sub-modules
Module 15 Syllabus (15.1-15.22)
EASA Part-66 Appendix I
Level 3
15.21 Engine Monitoring (B1)
EASA Part-66 knowledge levels
-47 C
Jet A-1 Max Freezing Point
DEF STAN 91-091 / Jet A-1 spec
EASA Part-66 Module 15 is the gas-turbine engine module sat by aircraft maintenance licence candidates in the Category A1/A3 and B1.1/B1.3 streams (it is not taken by B2/B3). For B1.1/B1.3 it is 92 multiple-choice questions in 115 minutes (A1/A3: 60 questions/75 minutes), passed at 75% - about 75 seconds per question. The real EASA exam uses 3-option MCQ; this free practice bank uses 4 options. The 22 sub-modules run from fundamentals (Brayton cycle, thrust, SFC, bypass ratio) and engine performance (EPR, flat rating) through the gas path (inlet, compressors with stall/surge and variable stator vanes, combustion, turbine creep and cooling, exhaust and thrust reversers), bearings and seals, lubricants and fuels, lubrication and fuel systems (hydromechanical and FADEC), air systems, starting and ignition, indication, turboprop/turboshaft/APU, installation and fire protection, to level-3 engine monitoring and ground operation. Content follows Regulation (EU) 2023/989, applicable 12 June 2024.
Sample Module 15 Practice Questions
Try these sample questions to test your Module 15 exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.
1The gas turbine engine operates on a thermodynamic cycle in which air is continuously compressed, heated at constant pressure, and then expanded through a turbine and nozzle. Which cycle is this?
2In a gas turbine, the four phases of the working cycle occurring continuously in different parts of the engine are:
3Gross thrust of a turbojet at a given operating point is calculated, ignoring fuel mass, as the mass flow multiplied by the jet velocity. Net thrust is obtained by:
4Specific fuel consumption (SFC) of a turbojet/turbofan engine is most correctly defined as:
5A high-bypass turbofan develops most of its thrust from:
6Bypass ratio of a turbofan engine is defined as the ratio of:
7A 'flat-rated' engine is one whose maximum rated thrust is held constant up to a particular ambient temperature. Above that 'kink-point' or 'corner' temperature, the rated thrust:
8Engine Pressure Ratio (EPR), used as a thrust-setting parameter on many turbofans, is the ratio of:
9As an aircraft climbs at constant Mach number, the thrust of a gas turbine generally decreases. The principal reason is:
10The primary purpose of the engine air intake (inlet) on a subsonic turbofan is to:
About the Module 15 Exam
EASA Part-66 Module 15 (Gas Turbine Engine) is the dedicated turbine-engine examination for candidates pursuing a Category A1/A3 or B1.1/B1.3 aircraft maintenance licence. It covers the theory and construction of gas-turbine engines from the Brayton cycle and engine performance through the inlet, compressors, combustion, turbine and exhaust, plus bearings, seals, fuel and oil systems, starting, ignition, indication, engine types, powerplant installation, fire protection and engine monitoring. For B1.1/B1.3 the exam is 92 multiple-choice questions in 115 minutes with a 75% pass mark. Content here follows the syllabus as amended by Commission Implementing Regulation (EU) 2023/989, applicable from 12 June 2024.
Questions
92 scored questions
Time Limit
115 minutes (B1.1/B1.3); 75 minutes for A1/A3 (60 questions)
Passing Score
75% per module
Exam Fee
Varies by NAA/Part-147 organisation (approx. EUR 50-230 per module sitting) (EASA framework; exams sat at National Aviation Authorities or approved Part-147 maintenance training organisations)
Module 15 Exam Content Outline
Fundamentals & Engine Performance
Brayton (constant-pressure) cycle and the four cycle phases, Newton's third-law thrust, gross/net thrust and ram drag, specific fuel consumption (SFC), bypass ratio, overall pressure ratio, engine pressure ratio (EPR), flat rating and thrust ratings, propulsive efficiency, and the thrust lapse with altitude (sub-modules 15.1-15.2)
Inlet, Compressors, Combustion, Turbine & Exhaust
Subsonic intake diffusion and bleed-air anti-ice, centrifugal vs axial compressors, stall and surge, variable stator vanes and handling-bleed valves, annular and multi-can combustors with duplex nozzles and swirl/dilution air, nozzle guide vanes, turbine fir-tree roots, creep, internal blade cooling, nickel superalloys, convergent and convergent-divergent nozzles, thrust reversers and noise suppression (15.3-15.7)
Bearings, Seals & Air Systems
Ball (thrust/locating) and roller bearings, labyrinth seals, the internal air system using P3 compressor delivery air for turbine cooling, bearing-chamber sealing and pressurisation, the centrifugal breather, and engine anti-ice air with overheat/leak monitoring (15.8, 15.12)
Lubricants, Fuels, Lubrication & Fuel Systems
Synthetic ester oils to MIL-PRF-23699/7808, Jet A-1 (freezing point about -47 C) and FSII anti-ice additive, pressure and scavenge pumps with greater scavenge capacity, hot- and cold-tank systems, magnetic chip detectors and filter impending-bypass indicators, hydromechanical and FADEC fuel control, gear-type fuel pumps, fuel-cooled oil coolers and the pressurising/shut-off valve (15.9-15.11)
Starting, Ignition & Indication
Start sequence and motoring, air-turbine and starter-generator starters, capacitor-discharge high-energy ignition, continuous ignition, hung and hot starts, EGT thermocouples and EGT margin, N1/N2 percentage rpm, EPR, torque on turboprop/turboshaft, fuel flow and vibration monitoring (15.13-15.14)
Engine Types, Installation, Fire & Ground Operation
Geared turbofan, open-rotor and hybrid-electric awareness, turboprop reduction gears with constant-speed governing and feathering, free-turbine turboshaft, APUs, power augmentation, QEC build-up and engine mounts, firewalls, fire detection and two-bottle extinguishing, and level-3 engine monitoring: boroscope, EHM/trend monitoring, ground run and storage/preservation (15.15-15.22)
How to Pass the Module 15 Exam
What You Need to Know
- Passing score: 75% per module
- Exam length: 92 questions
- Time limit: 115 minutes (B1.1/B1.3); 75 minutes for A1/A3 (60 questions)
- Exam fee: Varies by NAA/Part-147 organisation (approx. EUR 50-230 per module sitting)
Keys to Passing
- Complete 500+ practice questions
- Score 80%+ consistently before scheduling
- Focus on highest-weighted sections
- Use our AI tutor for tough concepts
Module 15 Study Tips from Top Performers
Frequently Asked Questions
Who takes EASA Part-66 Module 15?
Module 15 (Gas Turbine Engine) is taken by candidates for the Category A1, A3, B1.1 and B1.3 aircraft maintenance licences - the aeroplane-turbine and helicopter-turbine streams. It is not taken by B2 (avionics) or B3 (piston-aeroplane) candidates, and the piston-engine module (16) is separate.
How many questions are on Module 15 and how long is the exam?
For Category B1.1/B1.3 the Module 15 exam is 92 multiple-choice questions to be answered in 115 minutes (about 75 seconds per question). For Category A1/A3 it is a smaller subset of 60 questions in 75 minutes. The pass mark is 75%.
What is the pass mark and how is the exam scored?
Every EASA Part-66 module is passed at 75%. Module 15 is multiple-choice only - there is no essay (essays remain only in Module 7). The real EASA exam uses 3-option questions; this free practice bank uses 4 options to add challenge.
Does Module 15 follow the 2023/989 syllabus?
Yes. This practice content is built to the syllabus as amended by Commission Implementing Regulation (EU) 2023/989, applicable from 12 June 2024, which merged some former sub-module splits and added awareness of geared-turbofan, open-rotor and hybrid-electric concepts. Note that the UK CAA has diverged post-Brexit, so this content is EASA-specific.
What topics carry the most weight on Module 15?
The largest block is the engine gas path - inlet, compressors (with stall and surge), combustion, turbine (creep and cooling) and exhaust. Fundamentals and performance, and the fuel/oil/lubrication systems, are also heavily examined, with engine monitoring (15.21) uniquely taught at knowledge level 3 for B1.
How long should I study for Module 15?
Most candidates spend roughly 80-120 hours on the gas-turbine module, typically over 8-12 weeks alongside a Part-147 course. Strong grounding in the Brayton cycle, compressor airflow, and the fuel and oil system schematics pays off because many questions test cause-and-effect understanding rather than rote facts.