EUROCAE ED 179
MINIMUM AVIATION SYSTEM PERFORMANCE STANDARDS (MASPS) For ENHANCED VISION SYSTEMS, SYNTHETIC VISION SYSTEMS, COMBINED VISION SYSTEMS And ENHANCED FLIGHT VISION SYSTEMS
|Publication Date:||1 September 2011|
ED-179/DO-315 addressed Enhanced Vision Systems (EVS), Synthetic Vision Systems (SVS), and Combined Vision Systems (CVS) technologies. Currently, only EVS technology incorporating an approved Head-Up Display (HUD) is eligible for operational credit under Title 14 US Code of Federal Regulations (CFR) §91.175 with the Federal Aviation Administration (FAA). An approved combination of EVS and HUD is termed an Enhanced Flight Vision System (EFVS) by the FAA. The European Aviation Safety Agency (EASA) uses the term "EVS" as equivalent to the FAA description of EFVS. While further definitions are in Appendix A, it is important to understand this distinction before reading this document. This document adds performance standards for operational credit to touchdown in visibility as low as 1000ft RVR (or 300M if applicable), by use of an approved EFVS. Performance standards for this new operational capability are delineated throughout this document in order to maintain the unique characteristics of ED-179/DO-315 and ED-179/DO-315A. Performance standards for EFVS to landing (ED-179/DO-315A) include performance standards for EFVS approaches to 100 ft height above threshold elevation (THRE), formerly height above touchdown zone elevation (TDZE) (ED-179/DO-315). See notes below regarding change in terms of reference in ED-179/DO-315A.
The operational scenarios and concepts discussed in this document are written to describe the intended use of the proposed systems and from this context, associated minimum performance standards are derived. They do not define current or future operational regulations or limitations of these technologies.
Section 1 provides information needed to understand the rationale for system characteristics and requirements. This section also contains typical applications and envisioned operational goals and assumptions necessary to establish a basis for the subsequent sections. It describes typical applications and operational goals, as envisioned by members of RTCA Special Committee 213 and EUROCAE Working Group 79, and establishes the basis for the standards stated in Sections 2 through 4. Definitions and assumptions essential to proper understanding of this document are also provided in this section.
Section 2 describes minimum system performance requirements.
Section 3 contains the minimum performance standards and subsystem/function that is a required element of minimum system performance in Section 2.0. These standards specify the required performance under the standard environmental conditions described.
Section 4 discusses performance evaluations with applicable FAA and EASA regulations, describing the minimum system test procedures to verify system performance compliance (e.g., end-to-end performance verification). Compliance with these standards is recommended as one means of assuring that the system and each subsystem will perform its intended function(s) satisfactorily under conditions normally encountered in routine aeronautical operations for the environments intended. The Minimum Aviation System Performance Standards (MASPS) may be implemented by one or more regulatory documents and/or advisory documents (e.g., certifications, authorizations, approvals, commissioning, orders, advisory circulars, and notice.) and may be implemented in part or in total. Any regulatory application of this document is the sole responsibility of appropriate governmental agencies.
In this document, the term "shall" is used to indicate requirements. An approved design should comply with every requirement, which can be assured by inspection, test, analysis, or demonstration. The term "should" is used to denote a recommendation that would improve equipment, but does not constitute a requirement.
NOTE 1: 14 CFR § 91.175(l) refers to decision height (DH); however, this document uses DA/DH. For the purposes of ED-179A/DO-315A, the terms DA and DH are interchangeable.
NOTE 2: 14 CFR § 91.175(l) refers to descent to 100 feet height above touchdown zone elevation (TDZE). The FAA has recently instituted changes in the determination of instrument procedure minima to stop using TDZE to determine minima.
Future instrument approach minima (MDA or DA/DH) will be referenced to threshold elevation (THRE). The height value specified as MDA(H) or DA(H)/DH will be referenced to THRE for approaches with minima published after August 10, 2010. Existing published IFR approach minima and charting will gradually be changed to reference THRE and be displayed as a height above threshold (HATh). DO315A has adopted the use of THRE for all text whether 14 CFR § 91.175(l) "to 100 feet" or to touchdown. The former terms HAT or TDZE and new terms HATh or THRE are considered interchangeable relative to the requirements of this document and the intent of ED-179/DO-315