The book is intended specifically to meet the needs of the light aeroplane pilot. The 'Aeroplanes' section of this book satisfies the JAA/EASA PPL syllabus for the examination 'Aircraft (General)', and covers all of the systems which go to make up a modern light aeroplane: the electrical, electronic, mechanical and hydraulic systems, flight instruments, engine, propeller and engine instrumentation. Using this book, the student should acquire the theoretical and practical knowledge of his aeroplane's systems that he will need in order to fly his aeroplane efficiently and safely. The second section of the book, 'Mass & Balance', covers all the necessary knowledge and principles that the pilot needs to master in order to check that his aircraft is correctly loaded and balanced for safe and efficient operations. The loading of an aircraft not only affects the position of an aircraft's centre of gravity, but also determines whether the aircraft will achieve the required take-off performance, whether it can be landed safely, and at what speeds it can be safely manoeuvred. In addition to being safely loaded an aircraft must also be correctly balanced. Balance is related to the position of the centre of gravity. In whatever phase of flight the aircraft happens to be, it is vitally important that the location of the aircraft's centre of gravity always remains within the limits specified by the designer of the aircraft.