Acknowledgments US Department of Transportation - BTS

Table 2-15: Number of Pilot-Reported Near Midair Collisions (NMAC) by Degree of Hazard1980 1985 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008Total, all degrees of hazard 568 758 454 348 311 254 275 238 194 238 211 257 239 211 180 161 144 (R) 137 106 108 92Critical a 118 180 74 52 46 35 47 32 26 31 22 28 30 37 26 15 16 14 6 15 10Potential b 319 423 266 197 195 158 139 139 101 105 100 110 130 96 85 88 62 78 55 52 43No hazard c 122 133 114 99 70 61 71 63 55 70 53 55 49 51 42 37 31 20 17 21 11Unclassified d 9 22 0 0 0 0 18 4 12 32 36 64 30 27 27 21 35 25 28 20 28NMAC involving aircraft operating under 14 CFR 121 e U U 136 117 76 60 71 50 56 82 70 66 75 48 53 55 44 42 24 24 8KEY: R = revised, U = data are unavailable.aA situation where collision avoidance was due to chance, rather than an act on the part of the pilot. Less than 100 feet of aircraft separation wouldbe considered critical.bAn incident that would probably have resulted in a collision if no action had been taken by either pilot. Less than 500 feet would usually be requiredin this case.c When direction and altitude would have made a midair collision improbable regardless of evasive action taken.dNo determination could be made due to insufficient evidence or unusual circumstances, or because incident is still under investigation.eBefore Mar. 20, 1997, 14 CFR 121 applied only to aircraft with more than 30 seats or a maximum payload capacity of more than 7,500 pounds.Since Mar. 20, 1997, 14 CFR 121 includes aircraft with 10 or more seats that formerly operated under 14 CFR 125. This change makes it difficult tocompare pre-1997 data with more recent years' data.NOTESNMACs are reported voluntarily to the FAA so these numbers may not be representative. Reporters consist of pilots of air carriers, general aviationand other aircraft involved in public-use operations. Incidents involving military aircraft may be included if they also involved a civilian aircraft.SOURCESAll data except NMAC involving 121 aircraft:1980-85: U.S. Department of Transportation, Federal Aviation Administration, Aviation Safety Statistical Handbook Annual Report (Washington, DC:Annual issues) and personal communication, Aug. 6, 2002.1990-2011: Ibid., Aviation Safety Information Analysis and Sharing (ASIAS) System, NMACS Database Query Tool, available athttp://www.asias.faa.gov/portal/page/portal/asias_pages/asias_home/ as of May 2, 2012.NMAC involving 121 aircraft:1980-85: U.S. Department of Transportation, Federal Aviation Administration, Air Traffic Resource Management, personal communication, Aug. 6,2002.1990-2011: Ibid., Aviation Safety Information Analysis and Sharing (ASIAS) System, NMACS Database Query Tool, available athttp://www.asias.faa.gov/portal/page/portal/asias_pages/asias_home/ as of May 2, 2012.