Altitude and airspeed, represented as potential energy (EPOT) and kinetic energy (EKIN), respectively, can be thought of as constituting an aircraft’s total energy. Why do we care? Appropriate energy management (EM), maintaining a safe total energy state for all phases of flight, can help avert in-flight loss of control (LOC-I), the unintended departure of an aircraft from controlled flight and the leading fatal-accident cause.
Moreover, the FAA’s Airman Certification Standards (ACS) for private and commercial certificates specify that pilots are to have knowledge of EM concepts for many maneuvers. They include emergency approach and landing, soft-field/rough-field landing, normal approach and landing, short-field landing, various types of water landings, power-off 180-degree accuracy approach and landing and go-around/rejected landing. The word “knowledge” implies pilots should have, at least, a basic understanding of EM concepts and be able to apply these concepts to tasks in the FAA’s ACS.
