Analysis of Airprox in UK Airspace
Total Page：16
File Type：pdf, Size：1020Kb
FOREWORD The purpose of this, the 23rd Report from the UK Airprox Board, is to promote Flight Safety by publicising the circumstances and causes of Airprox with the aim of preventing repetition in the future. The Report provides a compendium of the all the Airprox reported as occurring in UK airspace during the period from 1 July 2009 to 31 Dec 2009. The number of Airprox during 2009 was the lowest for more than 10 years. The number of Airprox during the first half of the year was particularly low, but the in the second half of the year, the period covered by this Report, the rate of reporting increased to be close to that of the previous 5-year rolling average. Although not within the scope of this Report, the rate of reporting for 2010 is up again and close to the 10-year averages, despite the ash! Given the low number of events, caution is required in deducing trends from the data sets available over any 6-month period. Nevertheless, the most significant changes during the period Jul – Dec 2009, a marked reduction in Airprox involving Commercial Air Transport (CAT) and an increase in Airprox involving Military aircraft, both maintain trends established in previous years. In addition to noting the numerical values presented for the period Jul-Dec 2009, readers are invited to consider the statistics presented in the following pages as examples of the data available and possible comparators. As custodian of the Joint Airprox Recording System database, the Airprox Board is willing to assist any organisation or individual who seeks Airprox data for use in improving Flight Safety. Just ask. Ian Dugmore Director UK Airprox Board [email protected] INTRODUCTION AIRPROX DEFINITION An Airprox is a situation in which, in the opinion of a pilot or controller, the distance between aircraft as well as their relative positions and speed was such that the safety of the aircraft involved was or may have been compromised. UK AIRPROX BOARD (UKAB) The UKAB is an independent organisation sponsored jointly by the CAA and the MOD to deal with all Airprox reported within UK airspace. There are eight civilian and six military voting Members on the Board which is supported by specialist Advisers and chaired by the Director UKAB who reports directly to the Chairman CAA and Chief of the Air Staff, Royal Air Force. Board Members together form a team of hands-on practitioners with first-hand civil and military ‘know how’ on: Military and civil Air Traffic Terminal Control, Area Control and Airfield Control Fixed and rotary wing Commercial Air Transport (CAT) General Aviation (GA) flying, including gliding Fixed and rotary wing flying by the RN, Army and the RAF UKAB’s ROLE The UKAB undertakes the following tasks in promoting improved safety standards in the air: Act as the start point for an investigation process into each incident, generally carried out by the Safety Regulation Group (SRG) of the CAA and/or Military HQs Determine what happened and identify the main causal factors Assess the risk levels involved Make Safety Recommendations where appropriate to reduce the risk of recurrence Publish and distribute full reports so that lessons identified can be shared STATUS OF UKAB REPORTS The sole objective of the UK Airprox Board is to assess reported Airprox in the interests of enhancing flight safety. It is not the purpose of the Board to apportion blame or liability. To encourage an open and honest reporting environment, names of companies and individuals are not published in UKAB reports. RISK CATEGORIES Risk level assessments are made on the basis of what actually took place and not on what might have occurred. A Risk of collision An actual risk of collision existed B Safety not assured The safety of the aircraft was compromised C No risk of collision No risk of collision existed D Risk not determined Insufficient information was available to determine the risk involved, or inconclusive or conflicting evidence precluded such determination 1 THE UKAB DATA SET The UKAB Airprox database comprises a set of records each of which related to a specific Airprox. As an investigation proceeds, from first report until the conclusion of the Board’s deliberations, fields within the appropriate record are completed by the UKAB Secretariat. Analysis of the set of records is then possible to produce information such as is published in this Report. THIS REPORT The Report follows established practice by giving a broad overview on general trends and then examines in more detail some specific results for each of the three principal airspace user groups, Commercial Air Transport (CAT); General Aviation (GA) and Military. Some events, reported as Airprox and therefore assigned a reference number by the Secretariat, are subsequently withdrawn and are thus not subject to full investigation and assessment by the Board. Only the reporter can withdraw an Airprox. In this Report, numbers of ‘Unknown’ aircraft are added to ‘Untraced’ aircraft and weather balloons to produce the category, ‘Other’. Notes regarding the calculation of rates of occurrence: (1) CAT flying hour totals are supplied by the UK Civil Aviation Authority. Included are figures derived from Eurocontrol data on hours flown by commercial aircraft in transit through UK airspace as well as departures from and arrivals at UK destinations. (2) GA flying hours are supplied by the UK Civil Aviation Authority and are based on aircraft with less than 5,700Kg maximum take-off weight authorised. Gliders and microlights are included; gyroplanes, balloons and airships are excluded. General Aviation utilisation data is derived from the Aircraft Register and is formulated from the submissions provided by aircraft owners when Certificates of Airworthiness or Permits to Fly are renewed. Because Certificates of Airworthiness are normally renewed every three years, the hours flown by many aircraft will not yet have been reported. Utilisation figures for the last two- three years, as used in this publication, are therefore ‘best estimates’. Each year, past utilisation figures are reviewed and amended as appropriate with this revised data being reflected into the calculation of GA Airprox rates. (3) Military flying hours are supplied by the Ministry of Defence and by US Air Forces Europe. PUBLICATION OF REPORTS A key UKAB objective is to communicate effectively the lessons identified from Airprox events. Bi- annual ‘hardcopy’ Reports continue to be the primary means of communication, supported by presentations at flight safety meetings, cd-roms and the Internet. The UKAB Internet website is updated at least every month with details of recently assessed Airprox reports. The UKAB website address is www.airproxboard.org.uk 2 AIRPROX RESULTS FOR 2009 Numbers Of Airprox Figure 1 shows the cumulative distribution of Airprox for 2009 compared with the average for the previous 5 years. With no obvious technical or operational reasons for the reduction in Airprox over the year, it is assumed that much of it is due to reduced activity levels as a result of the recession. The incidence of Airprox in the second half of the year was much higher than the first half and close to the previous 5-year average. 250 All Airprox 200 A 150 i r p Mil Totals r 100 o x Mil Risk C Mil Risk B 50 Mil Risk A 0 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 Figure 1. Numbers of Airprox during 2009. In addition to the 147 Airprox that were fully investigated, 13 were withdrawn by the reporting pilot or controller prior to assessment by the Board. Withdrawals are usually a result of individuals reflecting on the circumstances of the occurrence, or in the light of emerging findings of the investigation. Trends By User Groups Airprox totals over the last 10 years are shown in Table 1 and Figure 2. Of the reduction in Civ-Civ encounters, most is a reduction Airprox involving CAT. Some of the increase in reported Mil-Mil Airprox appears to be as a result of a change in reporting culture. 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 Civil~Civil 100 97 109 87 109 99 95 93 93 74 Civil~Mil 78 73 77 67 69 74 46 38 38 36 Mil~Mil 18 20 31 23 22 8 12 12 17 30 Other 2 5 4 4 7 7 6 11 7 7 Totals: 198 195 221 181 207 188 159 154 155 147 Table 1. Airprox totals by main user groups. 3 250 200 Totals A i 150 r p r o 100 x Civil~Civil Civil~Mil 50 Mil~Mil 0 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 Figure 2. Airprox by User Groups. Trends by Flight Classification Expansion of the civilian user groups to show trends by flight classification is shown in Table 2 and graphically in Figure 3. There has been a steep fall in the number of CAT against CAT Airprox and the trend of CAT against GA aircraft continues downwards. Conversely, there has been a sharp rise in the number of Airprox involving Mil against Mil aircraft but, as noted earlier, at least some of this increase is a result of improved reporting. GA~GA 60 GA~Mil 50 A Figure 2. Airprox totals by main user groups. i 40 CAT~GA r CAT~CAT CAT~Mil p 30 r o 20 Mil~Mil x 10 0 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 Figure 3. Airprox trends by flight classification. 4 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 GA~Mil 44 45 57 42 47 43 25 25 24 29 GA~GA 35 45 51 47 55 46 44 46 47 46 CAT~CAT 36 30 39 13 28 10 19 19 24 11 CAT~GA 29 22 19 27 26 43 32 28 22 17 CAT~Mil 34 28 20 25 22 31 21 13 14 7 Mil~Mil 18 20 31 23 22 8 12 12 17 30 Other 2 5 4 4 7 7 6 11 7 7 Total 198 195 221 181 207 188 159 154 155 147 Table 2.