Plain English Meaning

It is the FAA standard that a piece of GPS equipment has to meet to be trusted for IFR navigation when it works together with WAAS. Equipment built to this standard is a position sensor that feeds another box, not an all-in-one navigator.

Full Definition

TSO-C145 is an FAA Technical Standard Order that sets the minimum performance requirements for a GPS navigation sensor that is augmented by a Satellite Based Augmentation System (SBAS), such as WAAS in the United States. A TSO-C145 unit is a sensor only — it provides position data to a separate flight management or , rather than being a complete standalone navigator. Equipment under TSO-C145 may be used to fly GPS and (GPS) , including and approaches, when installed and approved for that purpose.