Terminal Instrument Procedures (TERPS)

The purpose of the United States Standard for Terminal Instrument Procedures is to prescribe the criteria for the formulation, review, approval, and publishing of procedures for IFR (Instrument Flight Rules) operations to and from civil and military airports.

TERPS criteria have been established for the following Instrument Procedures: Precision Approach (PAR, ILS, MLS), Non-Precision Approach (VOR, TACAN, LNAV, NDB, ASR), Approach with Vertical Guidance (LDA, LPV, VNAV), Required Navigation Performance (RNP) and for Departure Procedures (DP).

The key considerations for developing Terminal Instrument Approach and Departure Procedures include but are not limited to, existing obstructions, ground/satellite-based equipment, lighting, and aircraft category.

TERPS criteria specify the minimum measure of obstacle clearance that is considered by the Federal Aviation Administration (FAA) to supply a satisfactory level of vertical protection from obstructions and are predicated on normal aircraft operations.

Understanding the complexities of Terminal Instrument Procedures is difficult since it is a highly specialized field requiring directed study and/or experience in its applications. 

An individual or company that has a requirement for outside expertise in this arena should engage an aviation consultant who has extensive expertise in developing innovative and workable solutions in the TERPS area of expertise.

Williams Aviation Consultants has successfully received favorable determinations from the FAA for our clients who had previously received a Notice of Presumed Hazard or a Determination of Hazard due to IFR impacts.