ANAC CEL Theoretical Exam (Airframe Group) study guide
ANAC CEL Theoretical Exam (Airframe Group) · Work through your exam, one topic at a time.
The CEL (Certificado de Licença de Mecânico de Manutenção Aeronáutica) theoretical exam for the Avionics group is the knowledge test that candidates in Brazil must pass as part of the licensing path for aircraft maintenance mechanics, administered under the supervision of ANAC, the national civil aviation authority. It is intended for people who have completed the required practical and training prerequisites and are ready to demonstrate theoretical competence before moving on to the practical and documentation stages of certification. The ANAC CEL Theoretical Exam (Airframe Group) study guide has 7 sections and about 2,233 words.
01Airframe Structures and Sheet Metal Work
The airframe is a semi-monocoque structure: skin carries shear and some tension, stringers and longerons stiffen it, frames and bulkheads maintain shape and carry concentrated loads, and the wing spar caps carry bending. Candidates must know the difference between primary, secondary and tertiary structure, and which repairs require an approved data source (SRM, AD, or engineering disposition).
355 words, about 2 min02Airframe Systems and Components
This domain covers pressurization, air conditioning, oxygen, fuel, ice and rain protection, and fire detection/extinguishing. Candidates must understand the pressurization cycle: outflow valve controls cabin altitude, cabin pressure differential is limited by a relief valve, and the pressure controller schedules climb and descent rates.
339 words, about 2 min03Electrical and Avionics Systems
Candidates must understand DC and AC power generation and distribution: batteries, starters, generators, alternators, inverters, transformers, rectifiers, bus bars, and circuit protection. Know the difference between a generator and an alternator (alternator produces AC rectified to DC; generator produces DC directly with a commutator).
342 words, about 2 min04Aircraft Materials, Hardware, and Corrosion Control
Know the common airframe materials: 2024 and 7075 aluminum alloys, 300-series stainless steel, titanium, magnesium, and composites. Understand temper designations (T3, T6, O, H) and how heat treatment affects strength and corrosion resistance.
306 words, about 2 min05Flight Controls, Hydraulics, and Landing Gear
Understand primary flight controls (ailerons, elevators, rudder) and secondary controls (flaps, slats, spoilers, trim). Know cable, push-pull rod, and torque tube systems, including tension regulators and fairleads.
283 words, about 1 min06Maintenance Practices, Inspection, and Documentation
Candidates must understand maintenance documentation: logbooks, work orders, inspection records, airworthiness directives, service bulletins, and approved data. Know the difference between a maintenance release, a certificate of airworthiness, and an annual inspection.
298 words, about 1 min07Brazilian Civil Aviation Regulations and Safety
This domain covers the Brazilian civil aviation framework administered by ANAC. Candidates must understand the roles of ANAC, the RBAC (Regulamento Brasileiro da Aviação Civil), and how RBACs align with ICAO Annexes.
310 words, about 2 min