General Aviation Safety Council A Study of Fatal Stall or Spin Accidents to UK Registered Light Aeroplanes 1980 to 2008 A Study of Fatal Stall or Spin Accidents to UK Registered Light Aeroplanes 1980 to 2008 A Study of Fatal Stall or Spin Accidents to UK Registered Light Aeroplanes 1980 to 2008 Preface GASCo wishes to thank the members of the stall/spin working group, who were: AvM John Brownlow, Member of the RAeS General Aviation Group, CB, OBE, AFC, FRAeS Former Test Pilot and GASCo Board Member Nigel Everett, MA(Cantab) Private Pilot and Editor of GASCo’s ‘Flight Safety’ Dr Guy Gratton, C.Eng, Test Pilot and Senior Visiting Research Fellow FRAeS, MIMechE, MSETP in Aeronautics, Brunel University Mike Jackson, BSc Private Pilot and GASCo Board Member (Maths and Statistics) Irv Lee, BSc(Aero Eng) GA Instructor and Editor of the GASCo ‘Fly on Track’ Web Site John Thorpe, FRAeS GASCo Chief Executive 2003-2010 Crown Copyright Special recognition is given to Mike Jackson and John Thorpe who were the principal compilers of this report. They undertook a very large amount of research and analysis for its preparation. Grateful thanks also to a number of senior instructors/examiners who gave their time for consultation during the research. These included: Pat Chandler, Paul Doble, Nick Goodwyn, Malcolm Hunt, Roger Mills, Patricia Nelmes, David Scouller, Chris Stringer, Barry Tempest. Photocopying of this study is permitted and short extracts can be published provided the source is duly acknowledged. Copyright © General Aviation Safety Council 2010. Crown Copyright A Study of Fatal Stall or Spin Accidents to UK Registered Light Aeroplanes 1980 to 2008 A Study of Fatal Stall or Spin Accidents to UK Registered Light Aeroplanes 1980 to 2008 Abstract Contents Examination of fatal aeroplane accidents between 1980 and 1. Introduction 2008 revealed that loss of control due to a stall or spin was the 2. Accidents & Aircraft Excluded from Analysis largest single factor, being present in 36% of them. 3. Analysis and Discussion 3.1 Annual Trend This study addresses single engine piston aeroplanes 3.2 Aeroplane Type excluding microlights, as defined in the Air Navigation 3.3 Weight Category Order 2009, and warbirds. The 110 accidents were 3.4 Activity and Circumstances analysed to determine the factors affecting each one 3.5 Location 3.6 Height 3.7 Stall Leading to Spin Amongst the findings were that: the accident rate for the Slingsby T67 j was throughout the period much greater 3.8 Type of Stall Warning than any other certified type and has been the percentage of fatal accidents due to treated as a special case; 3.9 Weather j stall/spin has remained almost unchanged during the period; with only one accident involving the 3.10 Pilot Experience Cessna 152 in 2.5 million flying hours, there has been a major change in the j 3.11 Disorientation and Distraction/Overload its record is similar to the tapered wing pattern of accidents during the period. j PA28, whereas the Cessna 150 K, L and Early in the period there was a high 3.12 Contribution of Engine and Airframe Problems M models have had eleven in one million percentage of accidents during low hours. Investigating this, Brunel University, 3.13 The Influence of Spectators aerobatics/displays/beat-ups which were Uxbridge have carried out flight trials all but eliminated towards the end of the on several Cessna 152, 150L and 150M 3.14 Presence of an Instructor period. Conversely, in the 1980s there aeroplanes using calibrated data recording was a very low percentage of accidents 4. Further Discussion equipment to determine control loads etc. following engine or airframe problems but This showed significant differences, e.g. 4.1 General since 2000 it has become the trigger for the stick force to stall the aeroplane was half of the accidents; greater in the C152 thus providing a better 4.2 Aeroplane Types there are marked differences in accident alert to the pilot; 4.3 Out of Balance rates per 100,000 hours between j turning finals was long held to be a high aeroplane types. Also, there are many 4.4 ASI markings risk point but the climb-out has now types with a significant number on the UK j replaced this; register and zero stall/spin accidents. For 4.5 Instructors instance, the Piper PA28 has the greatest it is a matter of concern to the group that 4.6 Flying Training Organisations number of hours of all types and every j in 22% of the accidents there was an one of the accidents were to the earlier instructor on board as a crew member, 4.7 Training constant chord wing version; although not always performing a training 5. Recommendations function. There has only been one fatal early in the period the stall/spin accident accident to a solo student since 1987; j rate for aircraft under 600kg max gross weight was very much greater than that apart from the Slingsby T67, no significant Table 1a Aeroplane Types with Fatal Stall - Spin Accidents for heavier types. Since 2000 the figures j problem has been revealed in spin have improved markedly, but are still recovery. Table 1b Aeroplanes with Three or More considerably greater; Accidents & Rates per 100,000 hours Table 2 Aeroplane Types with over 50 on UK Register & Zero Accidents For each of the accidents the Air Accidents Investigation Branch (AAIB) reports were carefully examined to enable a range of other possible causal factors such as weather hazards to be considered. Pilot experience and the influence of spectators were also analysed. Professional advice has been taken to ensure that none Appendix 1 Brief Tabulated Details of Fatal Accidents Reviewed of the findings were simply ‘statistical blips’. As a result of the investigation, nine Recommendations have been made covering education, certification, supervision and pilot training. Appendix 2 The Slingsby T67 01 A Study of Fatal Stall or Spin Accidents to UK Registered Light Aeroplanes 1980 to 2008 A Study of Fatal Stall or Spin Accidents to UK Registered Light Aeroplanes 1980 to 2008 02 1. Introduction 2. Accidents and Aircraft Excluded from Analysis a) During the period 1980 to 2008 there were 359 Fig. 1 Percentage of fatal accidents to a) Only fatal accidents were considered as these • jet powered aeroplanes (3 stall/spin fatal accidents to UK registered aeroplanes aeroplanes of 5,700 kg & less 1980 – 2008 are able to be precisely defined and have accidents); been fully investigated and comprehensively of 5,700 kg maximum gross weight and less. • microlights, as defined in the ANO, gliders reported by the Air Accidents Investigation After careful analysis of this total, 130 were (but motor gliders are included), helicopters Branch (AAIB), or where outside the UK, by found to be due to the pilot failing to maintain and gyroplanes; control resulting in a stall or a spin, i.e. 36%. the relevant foreign authority. A data base 10% of these accidents was available for this • the Slingsby T67, (8 fatal accidents) was These occurred in a variety of different types 12% of accident including the result of the pilot study and is summarised in Appendix 1. No excluded from the main numerical analysis deliberately low flying, performing a beat-up 36% comparable data base for non-fatal accidents but was studied as a special case ( See Appendix 2). or aerobatics close to the ground, during 13% is available, and the usefulness of the study display practice, losing control during a could have been compromised by a lesser forced landing, mishandling in the circuit or level of or non-existent investigation. This during training. Loss of control for reasons might have led to doubt as to whether stall/ c) There were a few ‘unusual’ accidents with other than stall/spin e.g. in Instrument 14% spin was a factor in the accident had the unique circumstances which it could be Meteorological Conditions (IMC), were not 27% study included findings of other possibly less argued should not be included in the analysis. considered. thorough investigations. Examples include three cases of pilots who were flying while under the influence of b) From Fig.1 it can be seen that during this 29 17% b) In order to concentrate the analysis on the alcohol or drugs, a case of carbon monoxide year period stall, which sometimes resulted sort of aeroplanes flown or owned by private poisoning, an unintended first flight and a in a spin, in visual flying conditions was the pilots, whilst providing a reasonably sized data pilot who had a heart attack during flight while sample, of the 130 fatal stall/spin accidents biggest single factor in fatal accidents. This 24% suffering from a major known but undeclared resulted in 216 deaths, more than 7 people 20% the following have been excluded from the medical condition. Nevertheless, these aircraft per year. Accordingly, GASCo established a analysis: stalled or spun and are therefore included in small working group (See Preface) to examine the analysis. the accidents in depth to determine the • twin-engine aeroplanes, (11 stall/spin accidents, most were loss of control after contributory factors and to propose measures Stall/spin VFR d) Thus during the 29 year period, the analysis is to reduce the number. These accidents were failure of one engine); left with 103 fatal stall/spin accidents involving studied in much greater depth than for the Flying rules broken • warbirds, including Harvards, (6 stall/spins, readily available single-engine aeroplanes, that CAA study of all fatal accidents 1985 to 1994, most frequently in an airshow/practice resulted in the death of 165 people.