Twenty-First Report by the UK Airprox Board: ‘Analysis of Airprox in UK Airspace’ (July 2008 to December 2008) produced jointly for The Chairman, Civil Aviation Authority and the Chief of the Air Staff, Royal Air Force 1 FOREWORD The primary purpose of this, the twenty-fi rst Report from the UK Airprox Board, is to promote air safety awareness and understanding of Airprox. “Book 21” covers the second half of 2008 in detail, containing fi ndings on all of the Airprox which were reported as occurring within UK airspace in that period and which were fully investigated and assessed by the UK Airprox Board. At the time of publication of “Book 20”, preliminary data for 2008 as a whole indicated that fi gures for the year would be in line with those for 2006 and 2007: that is, of the order of 155~160 Airprox fully investigated and assessed. That indication proved correct in that the fi gure for year 2008 was 155 against a ‘prior fi ve year’ average of 178. The total of 87 Airprox for the fi rst six months of 2008 was virtually equal to the average of comparable fi gures in each of the fi rst half of the preceding fi ve years whilst the total for the second six months of the year was some 22 below the historical average. As will be reported in due course, these lower fi gures at year-end 2008 are being maintained in the fi rst few months of 2009. In addition to the individual Airprox reports, almost all of which have already been published on the UK Airprox Board website - www.airproxboard.org.uk - this Report contains a range of graphs and tables highlighting many of the key statistics from UK Airprox throughout the whole of 2008. In this respect, the statistical sections herein follow the customary format. Although this Report is primarily intended for those who in one way or another are involved with aircraft and fl ying, it is understandable that people generally are interested in the safety of com- mercial air transport (CAT). In this regard, the total number of risk bearing Airprox in year 2008 and which involved at least one CAT aircraft is the lowest in the period 1999-2008: there were no Risk Category A occurrences and just two Risk Category B. Further information is given in the Commer- cial Air Transport section of this Report. It has long been part of the aviation safety culture for people to report openly any safety-related incident. This openness facilitates safety improvement action and the identifi cation of lessons for the benefi t of others. I am pleased to report that in general this spirit of openness continues, people being keen to ensure that others learn from the unfortunate situations in which they have found themselves and therefore being willing to cooperate fully with UKAB’s investigations. It is important that we sustain this culture for the future. By the time that you read these words, the handover to my successor is expected to be well un- derway, my ‘fi ve year term’ being at an end. I would again thank the air traffi c controllers and pilots who have been involved in Airprox and have subsequently participated in the investigations; the Members and Advisors of the UK Airprox Board; the Airprox Inspectors and UKAB’s administration team together with the many military and civilian specialists whose work contributes so much to the UK Airprox investigation system. If our collective effort helps to make fl ying safer – over the UK of course, and in other countries where this publication is also read – then all involved will have felt their efforts worthwhile. I close with my thanks and my customary plea that this Report be made freely available, in particular to pilots and air traffi c controllers, so that maximum fl ight safety value is gained from the work of the UK Airprox Board. Peter Hunt Director UK Airprox Board 2 CONTENTS Introduction Page UK Airprox Board (UKAB) Composition 4 UKAB’s Role 4 Status of UKAB Reports 4 Risk Categories 4 Airprox Defi nition 5 The UKAB Data Set 5 Airprox Results for 2008 Numbers of Airprox - 2008 6 Trends by User Groups 6 Airspace in which confl icts took place 7 Commercial Air Transport Section CAT Risk Results 7 CAT Airprox Rates 9 CAT Causal Factors 9 General Aviation Section GA Risk Results 10 GA Airprox Rates 11 GA Causal Factors 11 Military Aviation Section MIL Risk Results 12 MIL Airprox Rates 12 MIL Causal Factors 13 Airprox Trends 14 UKAB Safety Recommendations 15 List of Abbreviations 17 AIRPROX Reports: 094/08 to 170/08 19 - 237 AIRPROX Report: 147/06 investigated by the Irish Aviation Authority 238 3 INTRODUCTION UK AIRPROX BOARD (UKAB) COMPOSITION 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 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 fi rst-hand civil and military ‘know how’ on: • Air Traffi c Terminal Control, Area Control and Airfi eld Control, military and civil; • Commercial Air Transport (CAT) fl ying, both fi xed and rotary wing; • General Aviation (GA) fl ying, including gliding; and • Military fl ying, both fi xed and rotary wing, 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, identifying the main causal factors; • Assess the risk levels involved; • Make Safety Recommendations where appropriate to reduce the risk of incident recurrence; and • Publish and distribute full reports so that lessons identifi ed 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 fl ight 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’s reports. RISK CATEGORIES Risk level assessments are made on the basis of what actually took place and not on what may or may not have happened. There are four agreed categories as follows: 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 Insuffi cient information was available to determine the risk involved, or inconclusive or confl icting evidence precluded such determination 4 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. THE UKAB DATA SET The UKAB Airprox database comprises a set of records each of which relates to a specifi c Airprox. As an investigation proceeds, from fi rst report until the conclusion of the Board’s deliberations, fi elds 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 follows established practice, giving a broad overview on general trends and then examining in more detail some specifi c results for each of the three principal airspace user groups Commercial Air Transport (CAT); General Aviation (GA) and Military (MIL). To begin this review, Figure 1 overleaf shows the cumulative distribution of Airprox that were reported in 2008 and which were subsequently opened for full investigation. Please note that some events reported as Airprox are subsequently withdrawn and are thus not subject to full investigation. Only the reporter can withdraw an Airprox. Notes regarding the calculation of rates of occurrence:- (1) CAT fl ying hour totals are supplied by the UK Civil Aviation Authority. Included are fi gures derived from Eurocontrol data on hours fl own by commercial aircraft in transit through UK airspace as well as departures from and arrivals at UK destinations. (2) GA fl ying 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 Certifi cates of Airworthiness or Permits to Fly are renewed. Because Certifi cates of Airworthiness are normally renewed every three years, the hours fl own by many aircraft will not yet have been reported. Utilisation fi gures for the last two-three years, as used in this publication, are therefore ‘best estimates’. Each year, past utilisation fi gures are reviewed and amended as appropriate with this revised data being refl ected into the calculation of GA Airprox rates. (3) Military fl ying hours are supplied by the Ministry of Defence and its Contractors - Defence Equipment and Support - undertaking production and fl ight test activities and by US Air Forces Europe. In this Report, numbers of ‘Unknown’ aircraft are added to ‘Untraced’ aircraft and weather balloons to produce the category, ‘Other’.