Definition
The FAA's standardized criteria used to design instrument approach, departure, and en route procedures in terminal areas. TERPS specifies the obstacle clearance, descent gradients, turn areas, and protected airspace dimensions that every published instrument procedure in U.S. civil airspace must meet.
Plain English
TERPS is the rulebook the FAA uses when it draws up instrument procedures. It sets the safety margins — how far from terrain and obstacles a flight path must stay, how steeply it can descend, and how much room is needed for turns — so that any aircraft flying the procedure as published has guaranteed protection.
Context Anchor
Seen in instrument procedure design, approach chart discussions, and aircraft approach category explanations.
Derivation
Simply the spelled-out acronym: Terminal (the airspace near an airport) + Instrument Procedures (flight paths flown by reference to instruments). The name tells you the scope: it's the criteria for procedures used in the terminal environment.
Why Pilots Care
TERPS criteria directly affect the minimum altitudes, visibility requirements, and obstacle clearance on every instrument approach a pilot flies.
Analogy
TERPS is like a building code for instrument procedures: pilots use the finished structure, while procedure designers use the code to make sure it is built safely.
Intuition Check
TERPS is not a clearance you receive or a cockpit step you perform. It is the design standard behind the published instrument procedure.
Example Sentence 1
Circling minimums are based on aircraft approach category because TERPS uses category speed to determine how much protected airspace surrounds the airport.
Example Sentence 2
Pilots rely on TERPS-protected procedures when flying in instrument meteorological conditions.