AIS-AIMSG/6 – SN/2
10/05/12
AERONAUTICAL INFORMATION SERVICES-AERONAUTICAL
INFORMATION MANAGEMENT STUDY GROUP (AIS-AIMSG)
SIXTH MEETING
Buenos Aires, Argentina 21 to 25 May 2012
Agenda Item 6: Aeronautical information and data assembly, exchange, and promulgation
6.2: AM/SNOWTAM/ ASHTAM
NOTAM NUMBERING
(Presented by the Gregory Pray)
SUMMARY
The AIS-AIMSG is invited to discuss possible solutions related to the
problem of number rollover with the current four-digit numbering standard in
regions that issue large quantities of NOTAM. It is proposed that this issue be
further coordinated and studied by ICAO to determine a solution.
1.
BACKGROUND
1.1
The United States (US) is planning to provide ICAO compliant NOTAM by 2014. The
limitations in NOTAM numbering, however, have presented a challenge in the move toward compliance.
1.2
The current four-digit numbering standard for NOTAM allows for up to 9,999 unique
numbers. A particular challenge is developing a process to avoid a rollover in the allowed number when
more than 9,999 NOTAM are issued each year by a Flight Information Region (FIR) NOTAM Office
(NOF). This limitation in the NOTAM numbering would cause rollover in a number of the US FIRs.
2.
DISCUSSION/PROPOSED ACTION
2.1
One approach considered to avoid the rollover was to develop additional series of
NOTAM (i.e. specific to airports or navigation warnings) which has been adopted by other States to help
manage NOTAM processing and distribution. The US developed a matrix of several series of NOTAM to
seek a solution for avoiding the rollover problem. This option, shown at Appendix A, becomes complex
and possibly confusing for the user when considering such a large number of series along with the type of
coverage for each series. Fifteen of the series (in red letters in Appendix A) would be used to comply with
international civil aviation requirements while the remaining series would be used for the US Department
AIS-AIMSG/6 - SN/2
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of Defense and internal requirements. The results of an evaluation of the US 2010 NOTAM distribution
in Appendix B show the continued and potential rollover for some series. An additional point is that
systems in some States may not be able to handle such a large number of NOTAM series. Another option
was considered to establish additional FIRs/NOFs in a virtual sense, but that also proved not to be a
viable solution in the US.
2.2
The option of using a five-digit NOTAM numbering system was also evaluated. Such an
option would allow up to 99,999 unique numbers. This option, shown in Appendix C, would enable the
US to use far fewer NOTAM series. Six series of civil aviation NOTAM were initially considered to
manage NOTAM processing and distribution requirements. The preliminary assessment in Appendix D
shows that rollover is avoided. However, in the case of including the US domestic NOTAM, there is a
need to separate field condition NOTAM from the Series C for aerodromes into a seventh series. This
could be an option until the US considers the use of SNOWTAM or the future CONTAM (being
considered by ICAO for all aerodrome contaminates) to determine if these alternatives meet the
requirements.
2.3
The adoption of a five-digit NOTAM number standard may be able to help ease the
numbering problem in the US and other large systems such as regional systems covering more than one
State. It could also be considered for use in smaller systems where the need for a breakdown into more
series due to rollover of the four-digit limitation could be avoided. While this adoption may possibly
entail a simple software change in individual systems, the overall State and global system changes and
operational procedure changes are expected to be extensive.
2.4
The solution to the NOTAM rollover problem requires further, careful study. It is
proposed that this issue be considered by the AIS-AIMSG to request coordination and study within ICAO
to determine a solution to the current number rollover in regions that issue large quantities of NOTAM.
3.
3.1
ACTION BY THE AIS-AIMSG/6 MEETING:
The study group is invited to:
a)
discuss and comment on the content in this SN;
b)
agree on the need to resolve the limitations in the NOTAM number standard; and
c)
agree on the need for ICAO coordination and study of this issue.
————————
APPENDIX A
Option of Establishing Several Series of NOTAM in an Attempt to Avoid Rollover
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Series 11 April 2012
ICAO NOTAM CODE 2nd LETTER
A
B
C
D
E
F
G
H
J
X
LIGHTING FACILITIES
L
MOVEMENT AND LANDING AREA
M
X
AERODROME FACILITIES AND SERVICES
F
X
COMMUNICATION AND SURVEILLANCE FACILITIES
C
K
L
M
N
P
R
S
V
W
X
X
Y
Z
X
X
X
X
X
INSTRUMENT AND MICROWAVE LANDING SYSTEMS
I
TERMINAL AND ENROUTE NAVIGATION FACILITIES
N
X
AIRSPACE
A
PROCEDURES (Published, Flight)
P
AIRSPACE RESERVATIONS
R
AIR TRAFFIC AND VOLMET SERVICES
WARNINGS- RADIO ACTIVE, TOXIC CHEMICALS,
VOLCANIC ACTIVITY
S
V
X
NAVIGATION WARNINGS
W
X
X
OTHER INFORMATION
O
CHECKLIST
K
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
APPENDIX B
Continued and Potential Rollover after Establishing Several Series of NOTAM for International Distribution
using a Four Number Standard
Series
Keywords
ZAB
ZAN
ZAU
ZBW
ZDC
ZDV
ZFW
ZHN
ZHU
ZID
ZJX
ZKC
ZLA
ZLC
ZMA
ZME
ZMP
ZNY
ZOA
ZOB
ZSE
ZSU
ZTL
Total Sum
Percentage
NOTAMs Issued in 2010 by Crossover Airports by Series H, J, K & S
Series H:
Runway and
AD
Series J:
Series K:
Series S:
Facilities/
Taxiway and
Lighting
Surface
Services
Aprons
Systems
Conditions
AD, RWY,
SVC
731
10093
4533
3205
2598
1576
1556
544
1995
791
1297
1223
1139
1215
1436
439
2032
1986
1033
2542
1596
419
1119
45098
21.8%
TWY, APRON
648
1454
3633
1884
2545
4273
2423
484
1717
481
1185
1393
1167
315
1434
633
1699
2896
1243
1101
1278
83
717
34686
16.8%
AD, RWY,
TWY, SVC
426
1139
434
1096
789
608
541
816
1063
561
882
752
650
308
499
345
748
866
985
721
1136
63
723
16151
7.8%
FICON: AD,
APRON, RAMP,
RWY, TWY
63
21334
1039
2371
431
2927
253
0
22
1106
6
1268
0
487
2
51
2084
633
36
2436
560
0
133
37242
18.0%
FDC
329
207
349
984
1032
299
2889
610
921
429
625
644
1940
121
723
184
532
622
874
687
682
302
879
16864
--
APPENDIX C
Ae
ro
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rit
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om
Ad
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en
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en
Pr
se
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ur
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No
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In
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fo
AO
rm
Co
at
io
m
n
pl
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-C
nt
or
AD
re
ct
De
io
si
ns
gn
at
or
s
Option of Establishing Six Series of Civil Aviation NOTAM using a Five Number Standard
ICAO NOTAM CODE 2nd LETTER
C
D
E
G
L
M
V
W
X
LIGHTING FACILITIES
L
X
X
MOVEMENT AND LANDING AREA
M
X
X
AERODROME FACILITIES AND SERVICES
F
X
COMMUNICATION AND SURVEILLANCE FACILITIES
C
X
INSTRUMENT AND MICROWAVE LANDING SYSTEMS
I
X
TERMINAL AND ENROUTE NAVIGATION FACILITIES
N
X
AIRSPACE
A
X
PROCEDURES (Published, Flight)
P
AIRSPACE RESERVATIONS
R
X
AIR TRAFFIC AND VOLMET SERVICES
WARNINGS- RADIO ACTIVE, TOXIC CHEMICALS,
VOLCANIC ACTIVITY
S
X
V
X
NAVIGATION WARNINGS
W
X
OTHER INFORMATION
O
X
CHECKLIST
K
X
X
X
X
X
X
X
X
X
X
X
X
X
APPENDIX D
Results of Establishing Six Series of International Civil Aviation NOTAM using a Five Number Standard
International Distribution of Airport NOTAM Using Five Digit Numbers
with Six Series based on 2010 Data
Series V, W:
Series C Series G Procedures, Chart
Series
Aerodrome**
Obstructions
Corrections
AD, APRON,
RAMP, RWY,
SVC, TWY
OBST
ZAB
1868
255
329
ZAN
34020
126
207
ZAU
9639
420
349
ZBW
8556
938
984
ZDC
6363
960
1032
ZDV
9384
282
299
ZFW
4773
776
2889
ZHN
1844
215
610
ZHU
4797
2703
921
ZID
2939
302
429
ZJX
3370
1679
625
ZKC
4636
581
644
ZLA
2956
300
1940
ZLC
2325
335
121
ZMA
3371
995
723
ZME
1468
89
184
ZMP
6563
292
532
ZNY
6381
280
622
ZOA
3297
435
874
ZOB
6800
412
687
ZSE
4570
368
682
ZSU
565
1001
302
ZTL
2692
1169
879
133177
14913
16864
Keywords
Total Sum
— END —