update of aircraft crash rates used by hse in assessing ...military combat and jet trainers: all...

Update of aircraft crash rates used by HSE

in assessing hazards from chemical, process

and other major hazard installations

Prepared by the Health and Safety Executive

RR1140 Research Report

© Crown copyright 2019

Prepared 2017 First published 2019

You may reuse this information (not including logos) free of charge in any fo rmat or medium, under the terms of the Open Government Licence. To view the licence visit ww w.nationalarchives.gov.uk/doc/open-government-licence/, write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email [email protected].

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The Health and Safety Executive (HSE) provides advice on land use planning in the vicinity of major accident hazard

sites and major accident hazard pipelines. As part of this process, HSE publish a guidance document, Failure Rate and

Event Data, which contains failure rates for pieces of equipment found in major hazard chemical and process sites. The guidance document also contains information on

event data such as aircraft crash and flooding, which are used when assessing the risks from such major hazard sites.

An event such as an aircraft crash could lead to a release of a hazardous substance that could potentially harm people.

Th e aircraft crash rates were previously updated in 2009 using data up to 2006. This report updates the crash rates u sing data from 1990 to 2013. The methodology used to calculate the crash rates is also detailed. Uncertainty levels p rovide upper and lower bounds to the calculated crash rates to account for the uncertainty in the data that is used to derive the crash rates.

This report and the work it describes were funded by the Health and

Safety Executive (HSE). Its contents, including any opinions and/or

conclusions expressed, are those of the authors alone and do not

necessarily reflect HSE policy.

2

http://www.nationalarchives.gov.uk/doc/open-government-licence/

mailto:[email protected]

mailto:[email protected]

3

Update Lorem ipsu of aircraftm d croash rates lor sit aused bmet y HSE in

assessing

consectetuer adipiscing

hazards from chemical elit, proce ss


Zoe Chaplin Hea lth and Safety Executive Harpur Hill Buxton Derbyshire SK17 9JN

Acknowledgements

The author gratefully acknowledges the assistance received from Graham French of the Civil Aviation Authority (CAA), who provided data used in this report.

4

KEY MESSAGES

The Health and Safety Executive (HSE) provides advice on land use planning in the vicinity of major

accident hazard sites and major accident hazard pipelines. As part of this process, potential external

events are considered that could damage the site or pipeline. One of these events is aircraft crashes.

If an aircraft crash occurs, the equipment on the site can be damaged leading to a release of the

hazardous substance and potentially harming people. Information on aircraft crash rates was

previously updated in 2009 to use data up to 2006.

HSE have updated the aircraft crash rates currently used to incorporate data up to 2013.

The methodology used to calculate the crash rates had been reviewed and modified previously. Both

the current and revised methodologies have been detailed and the revised methodology was used

to update the crash rates.

5

EXECUTIVE SUMMARY

HSE provides advice on Land Use Planning (LUP) in the vicinity of major accident hazard sites and major accident hazard pipelines. As part of this process, HSE publish a guide to failure rates for vessels and pipework for use in LUP cases (hereafter referred to as Failure Rate and Event Data1). As part of this guide, external hazards are identified that may also need to be taken into consideration when assessing the hazards from chemical and process sites. One of these events is aircraft crashes. The aircraft crash rates and methodology reported in Failure Rate and Event Data were last updated in 2009 using data up to 2006.

This report is aimed at risk assessment modelling specialists for major accident hazard sites.

The available methodologies on calculating aircraft crash rates were reviewed in 2015 and some of the crash rates were recalculated using data from 1990 to 2013. It was decided that Failure Rate and Event Data should be modified to incorporate the more recent information. In addition, further information has been obtained to update the crash rates that were not considered as part of the recent review.

The crash rates are separated into two categories: background and airfield related. The background rates apply at distances greater than 5 miles from any airfield and relate to the cruising stages of flight. The airfield related crash rates apply within 5 miles of the airfield and are associated with the take-off and landing stages of flight.

The background crash rates and airfield related crash rates have been updated for five categories of aircraft. A 95% confidence interval has been included as part of the calculations to provide an indication of the level of uncertainty surrounding the data. The revised background crash rates are given in Table 1. Table 2 reports the revised airfield related crash rates.

Table 1 Calculated background crash rates (× 10-6 km-2 yr-1) for the period 1990 to 2013 for Great Britain.

Aircraft type Mean Lower confidence limit Upper confidence limit

Light aircraft 18.5 15.1 22.4

Small transport aircraft 2.2 1.1 3.8

Large transport aircraft 0.7 0.2 1.9

Helicopters 10.3 7.8 13.4

Military combat aircraft 6.7 4.7 9.2

Total 38.4 28.9 50.7

1 HSE (2012). Failure rate and event data for use within risk assessments (28/06/2012).

http://www.hse.gov.uk/landuseplanning/failure-rates.pdf

6


Table 2 Airfield related crash rates (× 10-6 per movement) for the period 1990 to 2013 for Great Britain





Civil helicopters 2.4 1.6 3.5


7

CONTENTS KEY M ESSAGES……………………………………………………………………. 5

EXECUTIVE S UMMARY 6 …………………………………………………………….

1 INTRODUCTION ............................................................................................. 9

2 METHODOLOGY .......................................................................................... 10 2.1 Current Methodology ..................................................................................... 10 2.2 Revised Methodology .................................................................................... 11

3 REVISED CRASH RATES ............................................................................ 12 3.1 Background crash rate................................................................................... 12 3.2 Airfield related crash rate............................................................................... 12

3.2.1 Small and Large Transport Aircraft ..................................................................................13

3.2.2 Light Aircraft ....................................................................................................................13

3.2.3 Helicopters .......................................................................................................................18

3.2.4 Military Combat Aircraft ..................................................................................................20

3.2.5 Summary of crash rates ...................................................................................................20

4 CONCLUSIONS ............................................................................................ 21

5 APPENDIX A: BACKGROUND RATE DATA............................................... 22

6 APPENDIX B: AIRFIELD RELATED RATE DATA....................................... 33

7 REFERENCES .............................................................................................. 47

8

1 INTRODUCTION

The Health and Safety Executive (HSE) publish a guide to failure rates for vessels and pipework for use in Land Use Planning (LUP) cases [1] (hereafter referred to as Failure Rate and Event Data). As part of this guide, external hazards are identified that may need to be taken into consideration when assessing the hazards from chemical, process and nuclear sites. The external hazards include lightning, flooding and aircraft crash.

Aircraft have the potential to crash onto a site, causing significant damage. As part of an LUP assessment, it is therefore necessary to consider the aircraft crash rate. The aircraft crash rates and methodology reported in Failure Rate and Event Data were last updated in 2009 using data up to 2006.

The crash rates are separated into two categories: background and airfield related. In both cases, crash rates are calculated for different types of aircraft (e.g. large transport, small transport, helicopters etc.). The background crash rates apply outside of a 5 mile radius of any airfield and relate to the cruising stage of flight. The airfield related crash rates apply within 5 miles of the airfield and are associated with the take-off and landing phases of flight.

In 2015, HSE reviewed the available methodologies on calculating aircraft crash rates as part of another project [2]. The background crash rates were also recalculated using data from 1990 to 2013, together with the airfield related crash rates for large transport aircraft. H SE therefore decided that Failure Rate and Event Data should be modified to incorporate the more recent information. In addition, the remaining airfield related crash rates that had not been considered as part of the earlier project should be updated.

The remainder of the report is structured as follows:

Section 2 provides an overview of the current methodology and details the revised methodology;

Section 3 details the calculations required to update the crash rates; and

Section 4 concludes the report.

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2 METHODOLOGY

Aircraft crash rates enable an assessment to be made of the hazard that an aircraft crash poses to a piece of infrastructure e.g. a chemical site, a nuclear plant etc. The methodology to calculate aircraft crash rates therefore needs to consider different types of aircraft as the hazards posed by them will vary e.g. a small aircraft is likely to cause less damage than a large passenger aircraft. The methodology must also be applicable to all sites located in Great Britain. This includes sites that are within 5 miles of an airport where airport specific crash rates are used, sites that are further away where a background crash rate will apply, and sites that have a significant number of military aircraft flying over them.

The details of the current methodology are given in Section 2.1 and the revised methodology is described in Section 2.2.

2.1 CURRENT METHODOLOGY

The methodology used in Failure Rate and Event Data is that of Byrne [3]. The methodology involves calculating background crash rates for different classes of aircraft across the UK. The background rates apply in areas that are at least 5 miles away from an airfield. The aircraft categories are:

Light aircraft: fixed wing aircraft of less than 2.3 te maximum take-off weight authorised (MTWA). It includes military light aircraft used for training that are less than 2.3 te MTWA;

Helicopters: all civil and military helicopters;

Small transport aircraft: fixed wing aircraft in the MTWA range of 2.3 te to 20.0 te, including civil and transport military aircraft;

Large transport aircraft: any other civil or military fixed wing aircraft not covered in the other categories; and

Military combat and jet trainers: all military fixed wing aircraft with MTWA up to 40 te to 50 te capable of aerobatic style flying.

Two areas of the UK are designated as being in high crash concentration zones for military aircraft. These are areas where low-level flying occurs. The crash rate applicable from military aircraft is adjusted if the site being assessed is within one of these zones. If the site is within a 50 km transition zone from a high crash concentration zone, then additional analysis is undertaken to adjust the military aircraft background crash rate.

Airfield specific crash rates apply if a site is within 5 miles of an airfield. In this case, crash rates have been derived per take-off and landing for each of the five aircraft categories. The rates calculated are assumed to apply for all airfields within the UK. The crash rates for each aircraft category are multiplied by the number of movements of that category of aircraft at the airfield in a typical year to derive a crash rate specific to an airfield. The likelihood that an aircraft will crash on a site as a result of a take-off or landing failure depends on the direction of the site from the airfield and the directions of the runways. A method is available to derive the frequency with which a unit ground area at a specified position relative to the runway would suffer an impact.

Beyond the 5 mile limit of an airfield, the background crash rates are assumed to apply.

Flight paths are also considered as part of the methodology. This allows particular airways to be considered when calculating the likelihood of a crash on a specific site.

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A worked example has been given in Failure Rate and Event Data, including assumptions about the type of vessel failure that could occur, depending on the type of aircraft involved and the distance from the vessel.

2.2 REVISED METHODOLOGY

The crash rates within Failure Rate and Event Data [1] used data on aircraft incidents up to 2006 and relied on the Byrne methodology report [3] from 1997. The methodology has been reviewed [2] and data from 1990 to 2013 has been used to update crash rates, where possible.

The main change to the use of the Byrne methodology has been to include levels of uncertainty around the calculated crash rates. It has been assumed that the background crash rates may be represented as a Poisson process [4] with rate parameter λ (i.e. the number of background crashes per year for a chosen area). The maximum likelihood method [5] has been used to estimate the value of λ and the chi-squared distribution [6] has been used to calculate 95% confidence intervals.

In the subsequent tables in this section, the calculated crash rate is given together with the lower and upper confidence interval limits. The calculated crash rate is based upon the data available and the lower and upper confidence limits give the 95% confidence interval range. In simple terms, the calculated value of the crash rate is the one based directly on the data and can be thought of as the “mean” value (this value is referred to as the mean subsequently in this report), whilst the confidence interval provides an upper and lower bound on the true value of the crash rate, i.e. it is a measure of the uncertainty in the process and can be thought of as limits on the true value of the crash rate.

For the airfield related crash rates, a Poisson process has again been used with the maximum likelihood method used to calculate the airfield related crash rate per flight movement. The chi-squared distribution has been used to calculate 95% confidence intervals. The flight path data has not been updated since that reported by Byrne [3] in 2007 due to the levels of uncertainty involved in the calculations and the lack of easily available data. The general trends in the data appear to indicate that aircraft reliability is improving. The use of the data from Byrne for the flight paths can therefore be considered as cautious.

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3 REVISED CRASH RATES

3.1 BACKGROUND CRASH RATE

The data and calculations for the background crash rate were updated for the Airports Commission [2] using the years 1990 to 2013. The incidents used in the calculations are reproduced in Appendix A. The calculated crash rates for Great Britain are given in Table 3 and are taken from the Airports Commission report.

Table 3 Calculated background crash rates (× 10-6 km-2 yr-1) for Great Britain for the period 1990 to 2013







Total 38.4 28.9 50.7

To understand the data in Table 3, the value of 2.2 × 10-6 km-2 yr-1 is the mean value calculated for the small transport aircraft crash rate for Great Britain i.e. the value calculated using the maximum likelihood method and based directly on the data. The value of 1.1 × 10-6 km-2 yr -1 is the lower end of the confidence interval and the value of 3.8 × 10-6 km-2 yr-1 is the upper end of the confidence interval.

The crash rates in Table 3 indicate that, across Great Britain as a whole, the total likelihood of a crash occurring is 38.4 × 10-6 km-2 yr-1, using the mean estimate.

In Failure Rate and Event Data [1], two areas of Great Britain were identified as being high crash concentration zones for military aircraft. This was based on data from 1996 to 2006. If the full set of data from 1990 to 2013 is considered, there appears to be a downward trend in the number of incidents. Only four incidents have occurred since 2004, of which none occurred in the previously identified high crash concentration zones.

When all 37 incidents are considered, there is a significant level of scatter in the locations. Whilst it may be possible to draw boxes around some of the incidents in some areas of the country, these will cover significant areas of the country and this could be considered a somewhat arbitrary approach that would be based on judgement rather than any specific criteria. It is therefore proposed that high crash concentration zones for military aircraft are no longer considered and the general background rate is applied to the whole country.

3.2 AIRFIELD RELATED CRASH RATE

The airfield related crash rate for small and large transport aircraft were calculated previously for the Airports Commission [2]. Crash rates were not calculated for the light aircraft, helicopter and military aircraft categories, however. These need to be calculated to allow crash rates associated with a specific airfield to be derived.

The number of movements for each category of aircraft per year from all airfields in Great Britain is required to calculate the crash rates,. The Civil Aviation Authority (CAA) records movements from

12

‘reporting’ airports. These are airports that are above a threshold in terms of the numbers of passengers or quantity of freight being transported.

For the small and large transport aircraft categories, this information is sufficient, as there are only a small number, if any, of small and large transport flights that occur at smaller airports.

For light aircraft and helicopters, however, there are a large number of small airfields from which flights occur and which do not report to the CAA. There are not many flights in these categories that do either take-off or land at the larger airports and so another source of information is required.

3.2.1 Small and Large Transport Aircraft

The airfield related crash rates for small and large transport aircraft have been taken from the Airports Commission report [2] and are shown in Table 13.

Table 4 Airfield related crash rates (× 10-6 per movement) for Great Britain




The results in Table 13 indicate that the airfield related crash rate for large transport aircraft is two orders of magnitude lower than that for small transport aircraft.

3.2.2 Light Aircraft

The number of light aircraft movements per year are required to calculate the light aircraft airfield related crash rate,. This information is not readily available, however, as small airfields are not required to provide movement data to the CAA. Instead, the number of movements has to be estimated using a number of other sources of data.

The General Aviation Small Aerodrome Research Study (GASAR) [7] assessed information obtained from questionnaires sent to a number of aerodromes in England, a large number of which are not ‘reporting’ sites for the C!! (i.e. they are not contained within the C!! data). From this, the G!S!R study was able to estimate that there were 4,347,000 General Aviation (GA) movements in England in 2002. GA movements are assumed to cover all aeroplane and helicopter flights other than those by major airlines or the Armed Forces.

The answers in the questionnaires also allowed a break-down to be made of the aircraft types at all airports in England. This is shown in Table 5. The GASAR study was concerned with GA movements and excludes aircraft owned by the major airlines.

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Table 5 Percentage of registered aircraft types at all airports in England from the GASAR [7] study

Aircraft category % of total number of registered aircraft

Helicopters 7

Jets 1

Single-Engined Piston 55

Multi-Engined Piston 6

Gliders 16

Microlight 13

Airship/Balloons 0

Others 2

Total 100

Table 5 shows that 61% of the aircraft fall into the light aircraft category, if it is assumed that all single- and multi-engined piston aircraft can be classified as light aircraft. In the GASAR study, single-engined piston aircraft were defined as being either over or under 750 kg whilst multi-engined piston aircraft were defined as being under or over 5,700 kg. These separate definitions were not used in the breakdown of registered aircraft by aircraft type, however, meaning that it is not possible to determine what proportion of the aircraft are below the 2,300 kg limit used as the light aircraft definition in this work. It may be assumed, however, that the majority of the single-engined piston aircraft will be below this weight.

The multi-engined piston aircraft are generally larger than the single-engined piston aircraft, but they make up a much lower percentage of the overall number of registered aircraft. Given the level of uncertainty surrounding the overall calculations, assuming a value of 55% of all GA movements for the number of light aircraft movements is not unreasonable. This leads to a total of approximately 2,400,000 light aircraft movements in England in 2002 that fall under the General Aviation category.

The CAA table of aircraft movements for 2002 [8] has been examined to estimate the number of movements in Scotland and Wales,. The proportion of Aero-club and private movements occurring in England, Scotland, Wales and Northern Ireland has been calculated and assumed to be representative of the proportion of light aircraft movements in each of the individual countries.

The number of Aero-club and private movements by country is shown in Table 6, together with the percentage of the total movements by country. Northern Ireland is shown as it is included in the CAA data and has a small effect on the final percentages, but Northern Ireland is not included in the analyses contained in this report, which concentrates on the crash rates in Great Britain.

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Table 6 Number of Aero-club and Private movements by country

Country No. of movements Percentage (%)

England 747,867 86.6

Scotland 64,325 7.5

Wales 39,017 4.5

Northern Ireland 11,929 1.4

Using these percentages and applying them to the 2,400,000 movements in England, implies a total number of light aircraft movements in Great Britain in 2002 of approximately 2,730,000 (i.e. not including Northern Ireland).

The number of movements for light aircraft for each year from 1990 to 2013 is required to calculate the aircraft crash likelihood. The CAA provided HSL with a spreadsheet containing the number of movements for each aircraft type from all the reporting airports (excluding Northern Ireland and the Channel Islands) for the years 1990 to 2013. The maximum take-off weight (MTOW) of the aircraft was included in the data, allowing the information to be split according to the aircraft categories used in this analysis. Table 7 lists the number of movements that fell into the light aircraft category by year.

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Table 7 Number of light aircraft movements by year from the reporting airports

Year Number of movements

1990 789

1991 911

1992 1150

1993 981

1994 197

1995 225

1996 42

1997 10

1998 5

1999 25

2000 7

2001 30

2002 5

2003 6

2004 3

2005 2

2006 0

2007 0

2008 0

2009 0

2010 0

2011 0

2012 1

2013 0

Total 4389

Table 7 shows that the number of light aircraft movements from the reporting airports increased until 1992, then decreased rapidly. Since 2002, there have been a negligible number of light aircraft movements. The number of movements in all the years is small compared to the total number of movements in this aircraft category across Great Britain as a whole. This means that it is difficult to deduce year-on-year changes in the number of movements from this data as there is a high level of uncertainty associated with the data.

An alternative method to assess the number of light aircraft movements is to use the Aero-club and private movements for a representative set of airports as reported by the CAA in Table 3.1 of the UK Airport Statistics [9]. Although the data in Table 7 indicates that the majority of these flights do not fall under the light aircraft category, the trends seen are considered to offer a reasonable representation of the trends in overall light aircraft movements, given the lack of any other available data.

The airports used for the analysis were Biggin Hill, Blackpool, Bournemouth, Dundee, Gloucester, Lydd and Shoreham as these have historically had a higher proportion of smaller aircraft flying from

16

these airports. Table 8 shows the percentage of Aero-club and private movements for each year when compared to 2002, together with the final calculated number of light aircraft movements. The previously calculated value of 2,730,000 movements for 2002 has been used as the baseline figure.

Table 8 Calculated light aircraft movement data

Year Percentage of 2002 Aero-club and private movements (%)

No. of light aircraft movements

1990 101.0 2,757,438

1991 80.8 2,206,133

1992 73.6 2,010,169

1993 83.1 2,268,420

1994 100.4 2,741,650

1995 115.4 3,149,752

1996 112.9 3,081,898

1997 114.9 3,136,504

1998 118.0 3,220,539

1999 112.7 3,076,540

2000 108.9 2,972,803

2001 112.5 3,071,368

2002 100.0 2,730,000

2003 110.0 3,004,348

2004 102.4 2,795,028

2005 102.1 2,788,450

2006 95.4 2,604,808

2007 88.1 2,405,617

2008 81.4 2,222,986

2009 80.4 2,194,946

2010 67.6 1,844,816

2011 68.7 1,875,959

2012 65.1 1,776,700

2013 63.2 1,725,089

Total - 61,661,959

Table 8 shows that the final total number of light aircraft movements for the period 1990 to 2013 is 61,661,959. Given the uncertainties and assumptions used, the value of 6 2,000,000 has been used in the subsequent calculations.

The total number of crashes between 1990 and 2013 are required to calculate the likelihood of a light aircraft airfield related crash. The recorded crashes are detailed in Table 21 in Appendix B and the total number of crashes is 152. The calculated crash rate, including the 95% confidence interval values, is shown in Tabl e 9.

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Table 9 Calculated light aircraft airfield related crash rates

Rate Crash rate (× 10 -6

) per movement

Mean rate 2.5

Lower confidence limit 2.1

Upper confidence limit 2.9

Table 9 shows that the mean airfield related crash rate for light aircraft is 2.5 × 10-6 per movement.

3.2.3 Helicopters

To calculate the airfield related crash rate for helicopters, the number of helicopter movements for the time period 1990 to 2013 is required. As in the case for light aircraft, the CAA only outlines information from ‘reporting’ airports, which does not cover a large number of sites where helicopters take off and land.

Four sources of information have been used to derive the helicopter movements:

“Public transport air taxi operations (a) for year 2002” published by the C!! [10];

“Aircraft movements 2002” published by the C!! [8];

“Passengers and air transport movements split by fixed wing and rotary wing aircraft 2002” published by the CAA [11]; and

The “General Aviation Small Aerodrome Research Study (GASAR)” published by UCL [7].

The first source [10] provides the breakdown by aircraft type of the air taxi stage flights in 2002 and has been used to derive a percentage of air taxi flights that were performed by helicopter. The calculated value is 74.8%.

The total number of Air taxi movements for 2002 for Great Britain was obtained from the CAA data [8] (noting that the movements associated with Northern Ireland were deducted from the total reported in the CAA table). This showed that there were 67,810 Air taxi movements in GB in 2002. Using the 74.8% obtained previously for the number of these flights performed by helicopter gives a value of 50,707 movements.

The third source [11] gives the number of air transport movements (as reported in Table 3.1 of the Airport Statistics [8]), minus the number of Air taxi movements, by fixed and rotary wing. There were 58,922 rotary wing movements in GB in 2002 that were not associated with Air taxis.

GASAR data [7] was used to calculate the number of helicopter flights associated with general aviation (GA) i.e. not associated with major airlines or the armed forces. From the GASAR data, as seen in Table 5 in Section 3.2.2, 7% of the GA flights were assumed to be by helicopters. The total number of GA flights in 2002 was 4,347,000, meaning that 304,290 were by helicopter. This data covers England only. Percentages of flights by country have been derived earlier in the report, using Aero-club and private data, as shown in Table 6. These percentages have been assumed to apply to helicopters as well, d ue to a lack of any other available data. This means that there were 346,455 GA helicopter movements in GB in 2002.

If the three calculated helicopter movements for 2002 are added together, the total number of movements is 456,084. Given the uncertainty involved in the calculations, a value of 456,000 has been used subsequently.

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To derive the number of movements by helicopter for each year from 1990 to 2013, Table 19 of the CAA Airport Statistics [9] for each year has been interrogated to obtain the number of rotary wing air transport movements (i.e. excluding Air taxis and general aviation). The percentage change from 2002 has been calculated and then applied to the total number of helicopter movements for 2002, i.e. 456,000. Table 10 reports the percentage of the 2002 rotary wing air transport movements for each year, the calculated number of helicopter movements for each year, and the total number of movements for the period 1990 to 2013. Data was unavailable for the years 1997 to 1999. For these years, the mean number of movements for the years 1994 to 1996 and 2000 to 2002 has been used.

Table 10 Calculated helicopter movement data

Year Percentage of 2002 rotary wing air transport movements (%)

No. of helicopter movements

1990 127.1 579,360

1991 128.6 586,264

1992 123.0 560,988

1993 120.3 548,381

1994 91.1 415,494

1995 99.9 455,721

1996 110.6 504,392

1997 99.7 454,824

1998 99.7 454,824

1999 99.7 454,824

2000 95.1 433,820

2001 101.6 463,515

2002 100.0 456,000

2003 91.7 418,071

2004 90.6 413,257

2005 100.2 456,727

2006 111.8 509,949

2007 119.9 546,880

2008 119.2 543,699

2009 118.7 541,091

2010 108.2 493,488

2011 113.3 516,868

2012 114.5 522,146

2013 130.6 595,705

Total - 11,926,286

The calculated total number of helicopter movements from Table 10 has been rounded to 12 million in the airport related crash rate calculations.

The final crash rate, including 95% confidence interval values, have been calculated using the total number of 29 crashes between 1990 and 2013 as reported in Table 22 in Appendix B. The helicopter airfield related crash rate is given in Table 11.

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Table 11 Calculated helicopter airfield related crash rates


) per movement

Mean rate 2.4



3.2.4 Military Combat Aircraft

The airfield related crash rate for military combat aircraft was calculated previously using data up to, and including, 2006 and was reported at the 50% confidence level. The report is not in the public domain, but a copy of the report has been made available to the project team. The number of military aircraft movements required to calculate the crash rate was not readily available and had to be derived using a complex method utilising worldwide data for UK military aircraft. Consequently, worldwide incident data was also required in the calculations.

No additional information has become available since the 2006 report. The report contains the necessary information to calculate the mean crash rate and the 95% confidence interval for the crash rate. This allows rates to be calculated that are consistent with the other aircraft crash rates calculated, but using the data available up to 2006 only. It is proposed that these rates are calculated using the information contained in the confidential report, noting that the crash rates are likely to be cautious as more crashes are likely to occur at unfamiliar sites, some of which may be in war zones. The crash rates are given in Table 12.

Table 12 Military combat aircraft airfield related crash rates


) per movement

Mean rate 3.5



3.2.5 Summary of crash rates

The final airfield related crash rates for the five aircraft categories are given in Table 13, together with the lower and upper confidence limits.








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4 CONCLUSIONS

The crash rates reported in HSE’s Failure Rate and Event Data [1] have been reviewed and updated to use data for the years 1990 to 2013, with the exception of the military combat aircraft airfield related crash rate which is based on information for the years 1990 to 2006 due to insufficient data being available after 2006. The methodology has been modified to include the use of confidence intervals, allowing for the uncertainty surrounding the data.

The revised background crash rates are given in Table 14 for the background crash rates and in Table 15 for the airfield related crash rates.

Table 14 Calculated background c rash rates (× 10-6 km-2 yr-1) for Great Britain for the period 1990 to 2013







Total 38.4 28.9 50.7








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5 APPENDIX A: BACKGROUND RATE DATA

This appendix contains tables of the crash data used in the analysis of the background crash rate. The locations of the incidents in these tables use the distance units (e.g. nautical miles, miles, kilometres, etc.) as recorded in the data. An aircraft crash is defined as an uncontrolled landing or mid-air break-up leading to serious damage to the aircraft and/or at least one fatality.

Table 16 Light aircraft background crashes, 1990 to 2013

Year (number

of crashes)

England Scotland Wales

1990 (5) 24.03.90 3 miles east of Mere

03.05.90 Chadlington

19.05.90 M25, Reigate1

19.05.90 M25, Reigate1

20.11.90 Dunbar Common, near Edinburgh

1991 (5) 18.04.91 Stanmore Common

19.05.91 Aldermaston

20.05.91 Near Lancaster

17.08.91 Ashampstead

15.05.91 Llangollen

1992 (7) 13.02.92 Skiddaw

15.02.92 M25/A13 near Thorrock

07.04.92 Consett

15.07.92 Forest of Bowland

09.12.92 8 miles west of Luton

03.04.92 Loch Muick

22.08.92 Isle of Jura

1993 (4) 21.03.93 Near Shrivenham

20.07.93 Shadoxhurst

18.03.93 3 miles south-west of Maybole

15.09.93 South-west of Sanquhar

1994 (6) 08.01.94 Wrekin

17.01.94 Thirlmere

20.01.94 Near Bloxwich

20.03.94 Near Wellesbourne Mountford

09.10.94 5 miles south-west of Binbrook

20.11.94 3 miles north of Worthing

1995 (3) 04.03.95 Near Malden, Essex

21.03.95 Knottingkey, Yorkshire

13.10.95 Sileay Ruy, Isle of Man*

22

Year (number

of crashes)


1996 (7) 05.05.96 Near Westcott

06.06.96 Pebworth, Near Evesham

15.06.96 Buxton

22.07.96 Tockington Park Farm, Near Almondsbury, Bristol

25.09.96 2 nautical miles west of Southport Pier

26.10.96 Dover VOR

16.10.96 18 nautical miles north-west of Perth

1997 (3) 27.11.97 1.8 miles north-west of Shobdon Airport, Herefordshire

06.05.97 3 nautical miles north of Cumbernauld Aerodrome

21.12.97 Near Ben House, Gatehouse of Fleet, Galloway

1998 (3) 26.07.98 Bentworth, Hampshire

20.10.98 Mow Cop House, Staffordshire

23.05.98 Tryfan, North Wales

1999 (7) 21.01.99 300 metres from western edge of Mattersey, Nottinghamshire

29.04.99 Near Selby, Yorkshire

04.07.99 Near Easingwold, Yorkshire

09.05.99 2 kilometres south of Cromarty, Black Isle, Highlands

12.02.99 Berwyn Mountain, mid Wales

02.08.99 Moel Hebog mountain, Near Beddlegert, North Wales

29.08.99 Sarn, Near Newtown, Powys

2000 (5) 15.05.00 Hambledon Hill, 15 miles north of Leeds Bradford Airport

16.07.00 Near Upper Cumberworth, West Yorkshire

30.11.00 Fortingall, Perthshire

13.12.00 En route Inverness to Benbecula

11.09.00 20 miles north of Swansea

2001 (6) 24.02.01 Near Sharpthorne, West Sussex

12.05.01 Osea Island, Essex

23.06.01 Nash, Shropshire

22.07.01 Near Lichfield, Hampshire

15.08.01 Halesworth, Suffolk

25.01.01 10 nautical miles south of Braemar, Grampian

23

Year (number

of crashes)


2002 (4) 27.02.02 Hannington, Hampshire

25.08.02 Devils Chair, Stiperstones, Shropshire

01.04.02 2 miles west of Cwmbran

18.05.02 12 nautical miles west of Brecon VOR

2003 (2) 05.01.03 2 miles north-east of Towcester, Northamptonshire

13.04.03 Clitheroe, Lancashire

2004 (4) 13.03.04 Hotham, South Cave, Humberside

27.06.04 Beacon Village, Near Honiton, Devon

04.07.04 offshore, in Liverpool Bay, 2 nautical miles north of Wallasey

22.10.04 37 miles northwest of Inverness

2005 (7) 25.05.05 Near Pottersbury, 6 miles north-west of Milton Keynes

15.06.05 Near Woltonunder-Edge, Gloucestershire

18.08.05 Remenham (Berkshire)

17.11.05 Near Bugbrooke, Northamptonshire

18.12.05 Moreton in Marsh, Gloucestershire

19.05.05 Approximately 20 miles north of Dundee

04.09.05 Irish Sea, 5 nautical miles north-west of Stumble Head, Pembrokeshire

2006 (3) 16.07.06 Hoxne, Suffolk

25.08.06 Near Bramley, South Yorkshire

11.09.06 Near Bethesda, Gwynedd

2007 (4) 03.02.07 Sea close to Blackpool beach

16.12.07 Near Rugely, Staffordshire

2

09.04.07 9 nautical miles south of Oban

01.06.07 Near Magar, Gwent

2008 (3) 13.02.08 Rutland Water, Near Empingham, Leicestershire

23.02.08 Farthing Common, Kent

05.04.08 Cairn Gorm, the Cairngorms

24

Year (number

of crashes)


2009 (5) 02.01.09 Colwich Junction, near Little Haywood, Staffordshire

10.04.09 Near Steep, Petersfield, Hampshire

14.06.09 Near Drayton, Oxfordshire

08.07.09 Bishop Norton, Lincolnshire

11.02.09 Near Porthcawl

2010 (4) 19.06.10 Castleford, West Yorkshire

10.07.10 Near Rotherfield Peppard, Oxfordshire

04.09.10 Near Ryde, Isle of Wight

26.11.10 Brecon Beacons

2011 (3) 21.03.11 Ingleborough, North Yorkshire

28.04.11 Near Malden, Essex

15.05.11 Near Witchampton, Dorset

2012 (1) 16.08.12 Near Bruera, Cheshire

2013 (1) 30.09.13 Near Bristol

Total (102)

73 16 13

*Isle of Man has been included as a British Crown Dependency 1Mid-air collision, counted as two separate impacts as ground impacts are different

2This was a crash involving a light aircraft and a small transport aircraft. A corresponding entry has been made

in Table 18

25

Table 17 Helicopter background crashes, 1990 to 2013 (military crashes in italics); only years with crashes shown

Year (number

of crashes)


1990 (3) 28.03.90 1 mile west of Chinnor

24.01.90 Giffnock 12.02.90 10 kilometres north-west of Valley

1991 (1) 08.09.91 Welford-on-Avon

1992 (4) 23.02.92 Royton

28.03.92 Coalport

29.05.92 Near Latimer

14.08.92 Crowthorne

1993 (5) 23.06.93 Near Kendal

20.07.93 Stanford Training Area

11.12.93 Near Wimborne

12.08.93

20.11.93

Llyn Padarn Lake

Near Brecon

1994 (3) 02.06.94

07.12.94

Mull of Kintyre

Ballachulish

22.05.94 Colwyn Bay

1995 (2) 07.04.95 Yarcombe, Somerset

05.10.95 Wye Valley, Chepstow

1996 (3) 23.04.96 1 nautical mile south of Portesham, Dorset

19.10.96 Near Cauldron Lowe, Staffordshire

22.10.96 Middlewich, Cheshire

1997 (3) 16.03.97 Gravesend near Albury, Heartfordshire

11.08.97 Adjacent to M6 motorway at Nether Kellet, Near Lancaster

14.11.97 Cocking, Near Chichester

1998 (3) 19.04.98 900 metres south-west of Gumley

26.07.98 Near Rochester Airport

01.08.98 Near Six Mile Bottom, Cambridgeshire

26

Year (number

of crashes)


1999 (1) 18.05.99 Tilton-on-Hill, east of Leicester

2000 (6) 01.02.00 2 nautical miles east of Chorley, Lancashire

08.03.00 Near Twyford, Berkshire

21.08.00 Dartford Marshes, Kent

23.08.00 Streatley, Berkshire

27.10.00 Inner sound between Island of Rona and Applecross

21.04.00 Coryton Drive, Cardiff

2001 (1) 16.11.01 Brunton

2002 (3) 13.07.02 Hampton Magna, Warwickshire

19.10.02 Wooferton, Shropshire

17.02.02 Near Muirkirk, East Ayrshire

2003 (4) 17.01.03 Cudham, Kent

10.04.03 Brightling, Sussex

02.12.03 Hurstbourne Tarrant, Near Andover

30.07.03 Carlenrig, Teviothead, Near Hawick

2004 (1) 11.11.04 Cophams Hill Farm, Bishopton, Warwickshire

2005 (1) 23.02.05 Salisbury Plain Training

2007 (4) 01.05.07 Near Thornhaugh, Peterborough

03.08.07 Near Kendal, Cumbria

08.08.07 Near Catterick, Yorkshire

15.09.07 Lanark

2008 (3) 26.01.08 Harrogate, North Yorkshire

28.05.08 Kingscott Valley, Devon

01.11.08 Winchcombe, Gloucestershire

2009 (2) 22.09.09 Near Stalmine, Lancashire

15.11.09 Macclesfield, Cheshire

2011 (1) 08.03.11 Keswick, Cumbria

27

Year (number

of crashes)


2012 (1) 06.01.12 Near Ely, Cambridgeshire

2013 (2) 16.01.13 Near Vauxhall Bridge, London

29.11.13 Glasgow

Total (57)

35 (44) 6 (8) 3 (5)

28

Table 18 Small transport background crashes, 1990 to 2013; only years with crashes shown

Year

(number of

crashes)


1993 (3) 13.01.93 Sellafield

11.06.93 Peak District, Broomhead Moor

15.08.93 Near Guildford, Surrey

1995 (1) 24.05.95 6 miles north-east of Leeds/Bradford International Airport

1998 (2) 28.11.98 Owlacombe Cross, Near Bickington, Devon (foreign registered)

24.12.98 1 nautical mile from the coast near Bradwell-on-Sea

1999 (1) 01.08.99 Woolaston, Gloucestershire

2000 (2) 18.08.00 Eastbourne, East Sussex

09.12.00 4 nautical miles north-west of Louth, Lincolnshire

2003 (1) 01.06.03 Borth, North Wales

2007 (1) 16.12.07 Near Rugeley, Staffordshire

1

2010 (1) 15.01.10 Bladon, Oxfordshire

Total (12)

11 0 1

Note: It is known that five of the six crashes that occurred between 1998 and 2003 involved privately owned ex-military jets (Hawker Hunter, two Jet Provosts, a Strikemaster and an Aero Vodochody Delfin). 1This incident was a crash involving a light aircraft and a small transport aircraft. A corresponding entry has been

made in Table 16.

29

Table 19 Large transport background crashes, 1990 to 2013; only years with crashes shown

Year (number

of crashes)


1990 (1) 30.04.90 30 feet below summit of Maodel, Isle of Harris

1993 (1) 27.05.93 8 nautical miles north-west of Blair Atholl

1994 (1) 25.02.94 Near Uttoxeter

Total (3) 1 2 0

30

Table 20 Military aircraft background crashes, 1990 to 2013; only years with crashes shown

Year (number

of crashes)


1990 (5) 09.01.90 Near Hexham, Northumberland

05.02.90 The Wash

10.04.90 North Dorchester, Dorset

02.05.90 Wells-next-the-sea, Norfolk

06.02.90 Capel-y-Ffyn, Powys

1991 (3) 25.09.91 Near Great Driffield, Yorkshire

10.05.91 Chepstow, Monmouthshire

29.08.91 Near Llanidloes, Powys

1992 (1) 02.04.92 Barton Hartshorn, Buckinghamshire

1993 (2) 28.06.93 Heckington, Lincolnshire

21.10.93 Near Barnard Castle, County Durham

1994 (2) 14.01.94 Aston Somerville, Worcestershire

01.09.94 Killin, Stirling

1996 (5) 10.02.96 Conningsby, Lincolnshire

1

10.02.96 Conningsby, Lincolnshire

1

23.02.96 6 nautical miles south of Taunton, Somerset

13.05.96 4 nautical miles west of Driffield, Yorkshire

28.09.96 Blackpool, Lancashire

1997 (1) 03.06.97 3 nautical miles south-west of Castle Douglas, Dumfries and Galloway

1998 (1) 18.12.98 2.5 nautical miles west of Staindrop, County Durham

31

Year (number

of crashes)


1999 (6) 21.01.99 Everton, near Retford, Nottinghamshire

09.07.99 22.5 nautical miles east-north-east of Cottesmore, Rutland

14.10.99 1.5 nautical miles south-east of Kirkheaton, West Yorkshire

22.10.99 10 nautical miles south of Penrith, Cumbria

14.07.99 7 nautical miles east of Coldstream, Berwickshire

17.11.99 1 nautical mile east of Torness, East Lothian

2000 (2) 18.10.00 Lowick, Northumberland

27.10.00 5 nautical miles north-east of Dumfries

2001 (2) 26.03.01 Ben McDui, Cairngorms

1

26.03.01 Ben McDui, Cairngorms

1

2002 (1) 17.05.02 Humber Estuary, Near Brough

2003 (1) 23.07.03 5 miles north-west of Pickering, North Yorkshire

2004 (1) 29.06.04 10 miles southwest of Boscombe Down, Wiltshire

2009 (1) 02.07.09 Glen Kinglass, Argyll

2011 (2) 20.08.11 River Stour, Southampton

27.01.11 Off Stornoway

2012 (1) 03.07.12 Moray Firth

Total (37)

24 10 3

1Mid-air collision, counted as two separate impacts as ground impacts are different

32

6 APPENDIX B: AIRFIELD RELATED RATE DATA

Data used in the calculation of the airfield related crash rates are listed in the subsequent tables.

Table 21 Light aircraft airfield related crashes, 1990 to 2013

Year (number

of crashes)


1990 (5) 18.03.90 Rattlesden, Suffolk

07.07.90 Cranfield, Bedfordshire

20.10.90 Near East Midlands Airport

05.04.90 On approach to

Glasgow Airport

27.05.90 Stoneykirk, Scotland

1991 (5) 10.03.91 Near Chilgrove, West Sussex

31.03.91 Coventry, West Midlands

11.04.91 North Weald

06.07.91 Winterbourne, Near Bristol

16.12.91 Chichester, West Sussex

1992 (3) 12.07.92 Oxford Airport

04.10.92 Sheepwash, Devon

06.12.92 Near Wycombe, Buckinghamshire

1993 (2) 03.10.93 Near Bridport, Devon

15.11.93 Near Biggin Hill, Kent

1994 (2) 01.08.94 Parham, Suffolk

26.12.94 Near Stapleford, Essex

1995 (4) 16.06.95 Dunkeswell Airfield, Near Honiton, Devon

09.07.95 Bakers Farm, Near Corby, Northamptonshire

20.07.95 Stourhead Gardens, Mere, Wiltshire

05.05.95 Newmill Farm, Dolphinton, Lanarks

33

Year (number

of crashes)


1996 (8) 02.03.96 Shoreham Airport

04.05.96 Old Warden Airfield, Bedfordshire

31.05.96 Lydd Airport

31.07.96 Canterbury Airfield

26.08.96 Near Barton Airfield, Manchester

21.11.96 Near Compton Abbas Airfield, Dorset

23.11.96 Denham, Middlesex

30.10.96 Cardiff

1997 (7) 06.03.97 3.5 miles northeast of Southend Airport

09.03.97 1 mile north-east of Biggin Hill Airfield, Kent

25.07.97 Meppershall Airfield, Bedfordshire

03.08.97 Near Shobdon Airfield, Herefordshire

08.08.97 Brunton Airfield, Northumberland

29.09.97 North Weald Airfield, Essex

20.08.97 Cardiff Airport

1998 (3) 17.05.98 Andrewsfield, Essex

09.08.98 Swanton Morley Airfield, Norfolk

15.08.98 Woburn Abbey, Bedfordshire

34

Year (number

of crashes)


1999 (10)

04.02.99 Turweston Aerodrome, Northamptonshire

28.03.99 Newnham, Hertfordshire

03.07.99 Bembridge Airport, Isle of Wight

17.07.99 East Mersea, Colchester, Essex

29.08.99 Husbands Bosworth Airfield, Leicestershire

18.09.99 Luton Airport, Bedfordshire

26.09.99 Charity Farm Airstrip, Baxterley, Warwickshire

06.10.99 Near Moneweden, Suffolk

14.11.99 Belle Vue, Barnstaple, Devon

18.12.99 Bournemouth International Airport, Dorset

35

Year (number

of crashes)


2000 (8) 04.03.00 RAF Cosford, Shropshire

24.03.00 Upwood Airfield, Cambridgeshire

19.04.00 2 nautical miles north of North Weald Airfield

1

19.04.00 2 nautical miles north of North Weald Airfield

1

12.05.00 Dunstable Downs Airfield, Bedfordshire

01.06.00 Rowley Mile Course, Newmarket, Suffolk

03.12.00 Warren Farm, Lambourne, Berkshire

30.12.00 Compton Abbas Airfield, Wiltshire

2001 (11)

14.02.01 Davidstow Airfield, Cornwall

27.04.01 Sherburn Airfield, Yorkshire

11.05.01 Full Sutton Airfield, Pocklington, Yorkshire

12.05.01 Leicester Airport

19.06.01 Near Southampton Airport

23.06.01 RAF St Mawgan, Cornwall

11.08.01 1 nautical mile north of Crompton Abbas Airfield, Dorset

02.09.01 Near Popham Airfield, Hampshire

14.09.01 Aston Down Airfield, Gloucestershire

28.12.01 Goodwood Aerodrome, West Sussex

18.05.01 Withbybush Airfield, Pembrokeshire

36

Year (number

of crashes)


2002 (5) 16.07.02 White Waltham Airfield, Berkshire.

21.07.02 White Waltham Airfield, Berkshire

22.08.02 Otherton Airfield, Staffordshire

03.11.02 Withycombe Farm, Oxfordshire

05.05.02 Strathallan Airfield, Perthshire

2003 (7) 15.02.03 Bowland Forest Gliding Club, Near Preston, Lancashire

29.03.03 Humberside International Airport

07.04.03 In a field close to Sandtoft Airfield, Humberside

31.05.03 Coventry Airfield

01.08.03 Horton Wood, Near Marlow, Buckinghamshire

06.12.03 Oxford Airport (Kidlington)

01.08.03 2 miles south-west of Hawarden Airport, Clywd

2004 (8) 01.02.04 Crowland Airfield, Lincolnshire

29.02.04 West Chiltington, West Sussex

30.03.04 Near Laneshaw Bridge, Colne, Lancashire

02.05.04 Bridge Farm, Acle, Norfolk

25.05.04 Popham Airfield, Hampshire

04.07.04 Lundy Island, North Devon

28.08.04 Bournemouth International Airport, Dorset

14.10.04 Wadswick Airstrip, Near Corsham, Wiltshire

37

Year (number

of crashes)


2005 (10)

08.02.05 Near Hormonden, Kent

25.03.05 Kinderton Lodge Farm, Middlewich, Cheshire

25.03.05 Kemble Airfield, Gloucestershire

30.04.05 Naish Farm, Clapton in Gordano, Bristol

02.05.05 Private airstrip, Near Keal Cotes, Lincolnshire

08.07.05 White Waltham Airfield, Berkshire

09.07.05 Milfield Airfield, Northumberland

07.08.05 Bracklesham Bay, West Sussex

22.10.05 Near Biggin Hill Airport, Kent

30.08.05 Rhigos, South Wales

2006 (7) 29.06.06 Near Thirkleby Hall, Thirkleby, North Yorkshire

19.07.06 Eastwood Park, Southend-on-Sea, Essex

22.07.06 Bournemouth Airport, Dorset

30.07.06 Popham Airfield, Hampshire.

05.08.06 Denham Green, Buckinghamshire

06.08.06 North Coates Airfield, Lincolnshire

25.09.06 Delamere, Near Chester, Cheshire

38

Year (number

of crashes)


2007 (12)

03.02.07 Blackpool, Lancashire

17.04.07 Near Nantwich, Cheshire

08.07.07 Clutton Hill Farm Strip, Bristol

29.07.07 Near Lechlade, Gloucestershire

05.08.07 0.5 nautical miles south-west of Sandown Airport, Isle of Wight

08.08.07 0.5 miles east of Leicester Airport

27.08.07 Near Stapleford Aerodrome, Essex

28.08.07 Near Exeter, Devon

16.09.07 Shotteswell, Near Banbury, Oxfordshire

06.10.07 Anwick, Lincolnshire

19.12.07 4 nautical miles south of Oxford Airport (Kidington)

01.06.07 Gwent, South Wales

2008 (4) 11.04.08 Highclere, Hampshire

23.07.08 City Airport Manchester, Barton, Eccles

26.07.08 Near Farthing Corner (Stoneacre Farm) Airfield, Kent

29.10.08 Seething Airfield, Norfolk

39

Year (number

of crashes)


2009 (6) 20.02.09 Wombleton Airfield, Harome, North Yorkshire

21.02.09 Fenland Airfield, Near Spalding, Lincolnshire

27.06.09 Great Oakley Airfield, Near Harwich, Essex

19.09.09 Bicester Airfield, Oxfordshire

20.09.09 Tangley, Hampshire

26.09.09 Humberside Airport, North Lincolnshire

2010 (3) 09.05.10 Northweald Airfield, Essex

09.05.10 Old Buckenham Airfield, Norfolk

28.11.10 Near Redland Airfield, Swindon, Wiltshire

2011 (9) 05.05.11 Private airstrip 19 nautical miles south-east of Penrith, Cumbria

26.06.11 North Coates Airfield, Lincolnshire

04.07.11 Shoreham Airport, West Sussex

1

04.07.11 Shoreham Airport, West Sussex

1

29.07.11 Eccles, Greater Manchester

02.09.11 Peterborough Sibson Airfield, Cambridgeshire

19.11.11 Henstridge Airfield, Somerset

18.12.11 Leicester Airport1

18.12.11 Leicester Airport 1

40

Year (number

of crashes)


2012 (7) 02.01.12 Stapleford Airport, Essex

10.01.12 Salisbury, Wiltshire

25.03.12 Godney Moor Airfield, Somerset

01.07.12 Old Warden Aerodrome, Bedfordshire

09.09.12 Private airstrip 4 nautical miles south-west of Bath

15.09.12 South of Popham Airfield, Hampshire

18.01.12 Near Welshpool Airport, Powys

2013 (6) 10.07.13 Abbots Bromley Airfield, Staffordshire

17.08.13 Felthorpe Airfield, Norfolk

21.08.13 Airstrip at Common Farm, Wymeswold, Leicestershire

24.10.13 Denham Aerodrome, Buckinghamshire

15.12.13 Netherthorpe Airfield, Nottinghamshire

19.5.13 Caernarfon Airport, Gwynedd

Total (152)

137 4 8

1Mid-air collision, counted as two separate impacts as ground impacts are different

41

Table 22 Helicopter airfield related crashes, 1990 to 2013; only years with crashes shown

Year (number

of crashes)


1990 (3) 27.06.90 Near Rocester, Staffordshire

13.07.90 Stanley, County Durham

31.08.90 Felsted, Essex

1991 (1) 10.03.91 Halifax, West Yorkshire

1996 (1) 16.12.96 Near Ledbury, Hereford

1997 (2) 16.01.97 Near Redhill, Surrey

13.07.97 Glamis Castle, Near Forfar

1998 (4) 28.01.98 1 nautical mile west of Souldern Manor, Oxfordshire

09.03.98 Amport, Andover, Hampshire

26.07.98 Near Rochester Airport, Kent

10.10.98 Sulby, Near Welford, Northamptonshire

2000 (2) 16.04.00 Carlisle Airport, Cumbria

02.12.00 Biggin, North Yorkshire

2002 (1) 24.05.02 Brough of Birsay, Orkney

2003 (2) 29.06.03 Shipham Airfield, Near Dereham, Norfolk

19.07.03 Knockholt, Sevenoaks, Kent

2004 (2) 03.03.04 1 mile east of Bournemouth Airport, Dorset

19.09.04 Kentallen, Near Oban

2005 (3) 08.05.05 Ockington Farm Strip, Near Dymock, Gloucestershire

15.03.05 7.7 nautical miles west-north-west of Campbeltown Airport, Argyll

21.12.05 3 nautical miles north east of Coupar Angus, Tayside

2006 (1) 01.06.06 Colliford Lake, Bodmin Moor, Cornwall

42

Year (number

of crashes)


2007 (1) 12.06.07 Near Codnor, Derbyshire

2008 (1) 28.07.08 Near Peacehaven, East Sussex

2010 (2) 24.05.10 Poundsgate, Devon

01.06.10 Loch Long, Near Arrochar

2012 (2) 14.08.12 Leicester Airport 16.01.12 Lake Vyrnwy, Powys

2013 (1) 19.06.13 Private landing site, Near Oxford

Total (29)

22 6 1

43

Table 23 Small transport airfield related crashes, 1990 to 2013;

only years with crashes shown

Year (number

of crashes)


1991 (2) 19.05.91 Brimpton Airfield, Near Aldermaston, Berkshire

30.06.91 Audley End, Essex

1992 (2) 27.06.92 Woodford, Manchester

06.10.92 Prestwick, South Ayrshire

1995 (3) 13.03.95 Near Andover, Hampshire

24.05.95 Near Leeds Bradford Airport

11.08.95 Fyfield, Near Andover, Hampshire

1996 (4) 14.07.96 Duxford Airfield, Cambridgeshire

21.07.96 Near Barton Airfield, Manchester

01.09.96 Crosland Moor Airfield, Huddersfield

19.05.96 Griesta, Near Lerwick

1998 (1) 05.06.98 Dunsfold Airfield, Surrey

1999 (1) 03.09.99 Near Glasgow Airport

2000 (3) 08.04.00 Goodwood Airfield, Chichester, West Sussex

14.06.00 Mersey Estuary, Near Liverpool Airport

23.12.00 Near Blackbushe Airport, Hampshire

2001 (3) 02.06.01 Biggin Hill Airfield, Kent

03.06.01 Biggin Hill Airfield, Kent

06.06.01 About 1 nautical mile east of Isle of Man Airport

*

44

Year (number

of crashes)


2002 (3) 04.01.02 Birmingham International Airport

02.06.02 Duxford Airfield, Cambridgeshire

24.12.02 Aberdeen Airport

2006 (2) 05.08.06 Derham Green, Buckinghamshire

06.09.06 Duxford Airfield, Cambridgeshire

2008 (2) 30.03.08 Romsey Close, Farnborough, Kent

17.08.08 Near Coventry Airport

2011 (1) 10.07.11 Near Duxford Aerodrome, Cambridgeshire

Total (27)

24 3 0

* Isle of Man has been included as a British Crown Dependency

Table 24 Large transport airfield related crashes, 1990 to 2013;

only years with crashes shown

Year England

1994 21.12.94 Coventry

1999 22.12.99 Near Stanstead

2008 17.01.08 Heathrow

45

Table 25 Number of movements and accidents for small and large transport aircraft for all major Great British airports, 1990 to 2013

Year Small transport Large transport

Number of movements Number of accidents Number of movements Number of accidents

1990 433,073 0 1,008,799 0

1991 448,331 2 959,437 0

1992 491,146 2 1,022,750 0

1993 375,547 0 953,800 0

1994 371,117 0 914,213 1

1995 382,031 3 974,702 0

1996 400,651 4 987,406 0

1997 344,525 0 1,049,038 0

1998 336,401 1 1,111,094 0

1999 323,119 1 1,203,737 1

2000 317,489 3 1,283,816 0

2001 305,282 3 1,395,012 0

2002 305,607 3 1,482,379 0

2003 324,214 0 1,552,876 0

2004 307,411 0 1,609,350 0

2005 279,958 3 1,636,419 0

2006 269,197 2 1,711,681 0

2007 288,890 0 1,800,839 0

2008 293,717 2 1,915,802 1

2009 309,379 0 1,946,788 0

2010 280,795 0 1,997,535 0

2011 264,147 1 1,959,003 0

2012 249,258 0 1,783,611 0

2013 226,036 0 1,688,761 0

Total 7,184,749 27 36,185,856 3

46

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https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/437269/operational-efficiency-ground-risk-analysis.pdf

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/437269/operational-efficiency-ground-risk-analysis.pdf

http://www.hse.gov.uk/research/crr_pdf/1997/crr97150.pdf

https://web.archive.org/web/20061007122800/http:/www.gaac.co.uk/gasar/GASAR_NationalPilotSurvey.pdf

https://web.archive.org/web/20061007122800/http:/www.gaac.co.uk/gasar/GASAR_NationalPilotSurvey.pdf

http://www.caa.co.uk/Data-and-analysis/UK-aviation-market/Airports/Datasets/UK-Airport-data/Airport-data-1990-onwards/









4

Published by the Health & Safety Executive 12/19

5

Update of aircraft crash rates used by HSE

in assessing hazards from chemical, process


The Health and Safety Executive (HSE) provides advice on land use planning in the vicinity of major accident hazard sites and major accident hazard pipelines. As part of this process, HSE publish a guidance document, Failure Rate and Event Data, which contains failure rates for pieces of equipment found in major hazard chemical and process sites. The guidance document also contains information on event data such as aircraft crash and flooding, which are used when assessing the risks from such major hazard sites. An event such as an aircraft crash could lead to a release of a hazardous substance that could potentially harm people.

The aircraft crash rates were previously updated in 2009 using data up to 2006. This report updates the crash rates using data from 1990 to 2013. The methodology used to calculate the crash rates is also detailed. Uncertainty levels provide upper and lower bounds to the calculated crash rates to account for the uncertainty in the data that is used to derive the crash rates.

This report and the work it describes were funded by the Health and Safety Executive (HSE). Its contents, including any opinions and/or conclusions expressed, are those of the authors alone and do not necessarily reflect HSE policy.

RR1140

www.hse.gov.uk

http://www.hse.gov.uk

update of aircraft crash rates used by hse in assessing ...military combat and jet trainers: all...

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