Definition
The difference between the aircraft's actual position and the position commanded by its flight guidance system. It measures how accurately the pilot or autopilot is following the displayed flight path, independent of any error in the navigation system itself.
Plain English
How far off the aircraft is from the path its instruments are telling it to fly. It measures the flying, not the navigation source.
Context Anchor
Seen in instrument flying, navigation performance, approach guidance, and discussions of how closely an aircraft must stay on a required path.
Derivation
The phrase isolates the 'technical' part of flying — the act of holding the commanded path. It separates pilot or autopilot tracking performance from errors in the navigation signal or aircraft position estimate.
Why Pilots Care
On precise routes such as RNP approaches, total navigation accuracy depends on keeping flight technical error small. Sloppy hand-flying or a poorly tuned autopilot can push the aircraft outside the protected airspace even when the navigation system is working perfectly.
Analogy
It is like trying to keep a car centered in a lane. The lane markings show where you should be; Flight Technical Error is how far you let the car move away from the center of that lane.
Grounding Statement
If the guidance shows the airplane should be on a certain path, Flight Technical Error is the amount the airplane is off that path.
Intuition Check
Flight Technical Error does not mean a mechanical problem or a mistake in the navigation database. It means the aircraft is not being held exactly on the commanded or desired path.
Example Sentence 1
The crew engaged the autopilot during the RNP approach to keep flight technical error within the required limits.
Example Sentence 2
During the approach the crew kept flight technical error low enough to stay within the required limits.