The Safety Analysis and Risk Mitigation Process  Section 3  43 3.5_SMSM_201904  Originally published April 2019  Uncontrolled copy when downloaded NAS equipment is subjected to thorough safety analysis through the FAA Acquisition  Management System (AMS). Refer to the  Safety Risk Management Guidance for System  Acquisitions, or go to the FAA Acquisition System Toolset website for more information on the  AMS. As such, the inherent functional severity of certain NAS equipment hazard effects has  been assessed and documented. When performing a safety analysis on NAS equipment that was previously assessed through  the AMS, it is recommended to use the data, methodology, and results of the previous work as  the starting point for the new safety analysis. If there are differences in functionality between  the original, previously assessed system and the system undergoing analysis, the differences  should be accounted for and documented in the new safety analysis.  In general, NAS equipment can fail such that one of two effects is expected:  When identifying functional failures that lead to hazards, the loss of function and the malfunction  of constituent parts must be considered. The severity of malfunctions and losses of function  from infrastructure systems, such as telecommunications and power systems, is dependent  upon the services they support. Examples of the systems that provide services include, but are not limited to, the following:  Navigation (NAV)  3.5.4.2.1 Assessing Severity of NAS Equipment Hazard Effects  Communication (COMM)  Surveillance  • Automatic Dependent Surveillance – Broadcast (ADS-B), Airport Movement Area Safety System (AMASS), Automated Radar Terminal System (ARTS), Airport Surface Detection Equipment (ASDE), Air Route Surveillance Radar (ARSR), Air Traffic Control Radar Beacon System (ATCRBS), Mode Select Beacon System (MODES), Wide Area Multilateration (WAM), and Standard Terminal Automation Replacement System (STARS) • Ground-to-ground COMM : Headsets/microphones, speakers, and voice switches • Air-to-ground COMM : Headsets/microphones, speakers, voice switches, radio control equipment, and radios • En Route guidance systems : Very-High Frequency Omnidirectional-Range Radio, Tactical Air Navigation, Distance Measuring Equipment, and Wide-Area Augmentation System • Instrument approach systems : Localizer, glide slope (e.g., visual glide slope indicators, such as Precision Approach Path Indicator and Visual Approach Slope Indicator), Ground-Based Augmentation System, markers, approach lights, Distance Measuring Equipment, Localizer-Type Directional Aid, and Runway Visual Range • Malfunction. The service is being provided inaccurately or with diminished integrity. • Loss of Function. The service is no longer provided.