A textbook for today's Commercial Pilot bridging the gap between theory and practice. This book expands on the basics learned by the private pilot for further preparation for the Commercial pilot written and practical tests. It provides a deeper and more technical look into aerodynamics, aircraft performance, stability, loading, flight planning, navigation, and meteorology. Then, advanced aircraft and systems are discussed to offer a basic familiarization with those craft typically flown by advancing pilots. These systems and techniques include constant speed propeller operation, retractable landing gear, fuel management, and oxygen & pressurization systems for high altitude flight. This book is detailed enough for complete understanding yet readable and practical enough for the typical commercial rated pilot.