Definition
Controlled airspace established to contain IFR operations transitioning between the terminal and en route environments. Transition areas extend upward from either 700 feet above the surface (when designated in conjunction with an airport for which an instrument approach procedure has been prescribed) or from 1,200 feet above the surface (when designated in conjunction with airway route structures or segments). Unless otherwise limited, transition areas terminate at the base of the overlying controlled airspace.
Plain English
A block of controlled airspace, starting at either 700 or 1,200 feet above the ground, that protects IFR aircraft as they move between airport approaches and the en route airway system.
Context Anchor
Seen in airspace and instrument flying discussions, especially when describing controlled airspace around airports and along routes.
Derivation
From Latin transire, meaning 'to go across.' The name reflects the airspace's purpose: it bridges the gap between two phases of IFR flight -- the terminal area near the airport and the en route airway structure at altitude.
Why Pilots Care
Pilots must recognize these areas to follow correct airspace rules, request appropriate services, and maintain separation during instrument approaches.
Grounding Statement
Picture an aircraft climbing away from an airport in poor weather: the transition area is the protected airspace that helps cover that climb until the aircraft joins the route structure.
Intuition Check
Do not read “transition area” as any place where a pilot changes tasks or flight phases. In this context, it means a specifically designated part of controlled airspace.
Example Sentence 1
The shaded magenta ring on the sectional shows the 700-foot transition area surrounding the airport's instrument approach.
Example Sentence 2
Reviewing the sectional chart, she noted the transition area surrounding the destination airport before planning her descent.