Definition
An approach to landing in which the aircraft is not maintained on the correct flight path, airspeed, descent rate, configuration, and power setting required for a safe touchdown. Specific stabilized-approach criteria vary by operator, but typically require the aircraft to be on the proper glidepath, on speed (within a defined tolerance), in landing configuration, with appropriate power set, and with only small corrections needed, all by a defined gate (commonly 1,000 feet AGL in IMC or 500 feet AGL in VMC). Failure to meet any of these criteria by the gate, or losing them afterward, makes the approach unstabilized and normally calls for a go-around.
Plain English
An approach where the airplane isn't settled into the correct path, speed, and configuration for landing by the point it should be. Things are still being chased or fixed instead of held steady, so the safe move is usually to go around and try again.
Context Anchor
Used during approach briefings, flight training, and landing decisions, especially when deciding whether to continue the landing or climb away and try again.
Derivation
From 'stabilized,' meaning held steady or in balance, with the prefix 'un-' meaning 'not.' An unstabilized approach is simply one that is not steady — speed, descent rate, or path are still changing in ways that need to be corrected.
Why Pilots Care
Recognizing an unstabilized approach allows the pilot to execute a go-around before the situation becomes dangerous.
Grounding Statement
A safe approach should look and feel steady before landing; if the airplane is still being forced into position late in the approach, it is unstabilized.
Intuition Check
Unstabilized does not mean the flight feels a little rough or imperfect. It means the approach is outside the safe conditions set for continuing to land.
Example Sentence 1
The crew was high and fast crossing 500 feet, recognized the unstabilized approach, and called for a go-around.
Example Sentence 2
During the lesson the instructor demonstrated how an unstabilized approach develops when the pilot fails to adjust power early.