Definition
The combined sum of an airplane's potential energy (energy of altitude) and kinetic energy (energy of motion) at any given moment. Total energy can be traded between altitude and airspeed, but it can only be increased by adding power and decreased by using drag.
Plain English
How much energy your airplane has overall, counting both how high it is and how fast it is going. You can swap one for the other, but to actually have more energy you need power, and to have less you need drag.
Context Anchor
Seen in airplane energy-control discussions, especially during climbs, descents, approaches, and landings when the pilot is managing pitch and power.
Derivation
Total comes from the Latin totus, meaning “whole” or “entire.” Energy comes from a Greek word meaning “activity” or “work.” Together, total energy points to the whole amount of usable motion-and-height energy the airplane has.
Why Pilots Care
Pilots use total energy concepts to safely manage speed and altitude trades, preventing stalls or insufficient energy for landing.
Analogy
Think of total energy like money split between two pockets. One pocket is altitude and the other is speed. The total amount matters, even if you move some from one pocket to the other.
Grounding Statement
Think of total energy as a fuel tank you can pour between two cups labeled 'altitude' and 'airspeed.' The pitch lets you pour between cups; the throttle refills the tank; drag drains it.
Intuition Check
Total energy does not mean engine power alone. Here it means the airplane’s combined energy from both altitude and speed.
Example Sentence 1
On a high, fast approach the pilot had too much total energy, so they reduced power and added drag with flaps to bring it back into range.
Example Sentence 2
During the approach, excess total energy required a go-around decision.