The Instrument/Commercial Manual is your primary source for initial study and review to achieve an instrument rating or commercial pilot certificate. The intuitive organization and colorful presentation of the manual will help you learn quickly from the start. The text contains complete and concise explanations of the advanced concepts and ideas that every instrument and commercial pilot needs to know with the subjects arranged in a logical manner to build upon previously introduced topics. You can expand your knowledge of specific subjects and the world of aviation by exploring the Discovery Insets, which are strategically placed throughout the chapters. To help you understand how your mind and body function while you fly, human factors principles are presented in Human Element Insets. Throughout the manual, concepts that directly relate to FAA test questions are described in FAA Question Insets. To help you effectively review material, key terms are highlighted throughout the text and listed at the end of each section along with a checklist, which summarizes important concepts. Additionally, you can evaluate your understanding of material by completing the associated questions at the end of each section.