EASA 021

Aircraft General Knowledge

EASA PPL subject 021 — engines, instruments & systems

Aircraft General Knowledge (021) covers everything about the aircraft itself: from the workings of the piston engine to gyroscopic instruments, from fuel management to the electrical system. A solid understanding of this subject makes you a better and safer pilot.

Topics covered

  • Piston engine: operation, cooling, lubrication and carburettor
  • Propeller: fixed pitch, variable pitch
  • Gyroscopic instruments: artificial horizon, compass, direction indicator
  • Pitot-static system: airspeed indicator, altimeter, variometer
  • Fuel management: mixture, tank capacity, vapour lock
  • Electrical system: battery, alternator, fuses
  • Hydraulic system and landing gear

Study tips for Aircraft General Knowledge

1

Connect theory to the preflight check: understand why you check each item.

2

Draw the engine cycle step by step: visualising helps memorisation.

3

Focus on failures: the exam asks a lot about what can go wrong and how you respond.

4

Use the POH (Pilot's Operating Handbook) of a Cessna 172 as a study guide.

Specialists for Aircraft General Knowledge

These coaches and tutors specialise in this subject.

A.D.
Subject Expert Technical Subjects

Flight Instructor FI(A) with an MSc in Aerospace. Active instructor and the go-to person for everything related to aircraft systems, aerodynamics and weather.

  • Aircraft General Knowledge (021)
  • Principles of Flight (081)
  • Meteorology (050)

Need broader support?

These coaches support your broader PPL journey and study planning.

Ready to tackle Aircraft General Knowledge?

Book a free intro call with one of our specialists for subject 021.