CAP 763

CAP 763 Aviation Safety Review 2005
UK Airspace and Aerodromes - Airprox
500
450
400
Not involving loss of separation
Involving loss of separation
Number of level busts
350
300
250
200
150
100
50
0
1995 1996 1997 1998 1999 2000 2001 2002 2003 2004
Figure 6.8
Level busts in UK airspace
3.9.3 It should be noted that there are a number of level busts in this section that resulted
in an Airprox. However, as the figures are small (only 5% of the total) these Airprox/
level bust occurrences have been kept in the dataset.
3.10 Other types of ATC occurrences
3.10.1 Apart from runway incursions and level busts there are other significant types of ATC
occurrence, as shown in Table 6.6. It should be noted that these occurrences are not
necessarily mutually exclusive, e.g. a loss of separation could arise from a call sign
confusion incident. These occurrences involved at least one civil aircraft.
Occurrence Type 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Total
ATS Engineering/
Equipment
304 420 512 432 529 592 555 826 587 560 5317
Call-sign Confusion 91 90 182 147 105 96 83 108 137 106 1145
Infringements 240 282 348 270 350 303 273 350 419 405 3240
Loss of Separation 176 223 241 257 270 274 208 223 198 246 2316
Table 6.6
Other significant ATC occurrences
4 Airprox in UK Airspace
4.1 The definition of 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.
4.2 Airprox within UK airspace are reviewed separately by the UK Airprox Board (UKAB)
which is an independent organisation sponsored jointly by the CAA and the MOD.
UKAB determine what happened in each Airprox, assess the risk level involved and
make Safety Recommendations, where appropriate, to reduce the risk of recurrence
of such incidents.
8 August 2006
Chapter 6 Page 9