Near Midair Collision Reporting


  • Near Midair Collision (NMAC) reporting provides information for use in enhancing the safety and efficiency of the National Airspace System
  • Data obtained from NMAC reports are used by the FAA to improve the quality of FAA services to users and to develop programs, policies, and procedures aimed at the reduction of NMAC occurrences


  • A near midair collision is defined as any incident associated with the operation of an aircraft in which a possibility of collision occurs as a result of proximity of less than 500' to an other aircraft, or a report is received from a pilot or a flight crew member stating that a collision hazard existed between two or more aircraft
Hudson Mid Air Collision
Figure 1: Hudson Mid Air Collision

Reporting Responsibility:

  • Responsibility of the pilots to determine whether a near midair collision did actually occur, and if so, initiate a report
  • Pilots must state clearly "I wish to report a near midair collision"

Where to File Reports:

  • Pilots and/or flight crew members involved in NMAC occurrences are urged to report each incident immediately:
    • By radio or telephone to the nearest FAA ATC facility or FSS
    • In writing, in lieu of the above, to the nearest Flight Standards District Office (FSDO)

Items to Report:

  • Date and time (UTC) of incident
  • Location of incident and altitude
  • Identification and type of reporting aircraft, aircrew destination, name and home base of pilot
  • Identification and type of other aircraft, aircrew destination, name and home base of pilot
  • Type of flight plans; station altimeter setting used
  • Detailed weather conditions at altitude or flight level
  • Approximate courses of both aircraft, indicate if one or both aircraft were climbing or descending
  • Reported separation in distance at first sighting, proximity at closest point horizontally and vertically, and length of time in sight prior to evasive action
  • Degree of evasive action taken, if any (from both aircraft, if possible)
  • Injuries, if any

The Investigation:

  • The FSDO in whose area the incident occurred is responsible for the investigation and reporting of NMACs
  • Existing radar, communication, and weather data will be examined in the conduct of the investigation
  • When possible, all cockpit crew members will be interviewed regarding factors involving the NMAC incident
  • ATC will be interviewed in cases where one or more of the involved aircraft was provided ATC service
  • Both flight and ATC procedures will be evaluated
  • When the investigation reveals a violation of an FAA regulation, enforcement action will be pursued


  • All NMAC reports are thoroughly investigated by Flight Standards Facilities in coordination with Air Traffic Facilities
  • Data from these investigations are transmitted to FAA Headquarters in Washington D.C., where they are compiled and analyzed, and where safety programs and recommendations are developed
  • More information can be found by visiting: FAA Aviation Safety Information Analysis and Sharing (ASIAS) or,