Attachment 2: SADIS Gateway Development Team Internal WPs
Circulation / Paper Number / Title1. / 1/04 / Working Paper 1 / SIGMET Correction on SADIS
2. / 1/04 / Working Paper 2 / SADIS Gateway Real Time Monitoring
3. / 1/04 / Working Paper 3 / The Impact of BUFR on the SADIS Gateway
SADIS Gateway Development Team
Circulation 1/04 Mar-Apr 2004 Working Paper 1
SIGMET Correction on SADIS Gateway
(Prepared by the UK)
1. Introduction
1.1 The procedures for the validation and correction of alphanumeric met data are published in the SADIS Gateway Operations Handbook. This ensures that SADIS users are aware of what corrective action may be carried out on non-compliant messages. Since the introduction into operational service of the SADIS Gateway a number of additional problems with SIGMET data have been identified. This paper is intended to describe these problems and the procedures used by operators to deal with them. These procedures are for review with the intention of producing a Working Paper for the SADISOPSG for modifications to be made to the SADIS Gateway Operations Handbook.
2. New SIGMET problems
2.1 The following SIGMET related data problem been observed on the SADIS Gateway. In the example below the SIGMET was rejected because the message did not have an ATSU indicator at the start of the line following the Abbreviated Header Line (AHL).
WSMC31 GMMC 020730
SIGMET 2 VALID 020730/021030
CASABLANCA FIR ISOL EMBD TS OBS ANF FCST NORTH OF 33N TOP FL300 MOV
SLW E NC =
2.2 In the example below the SIGMET was rejected because the message did not have an ATSU indicator at the start of the line following the Abbreviated Header Line (AHL) that is recognised by the system.
WSNO32 ENMI 270256
ENOR SIGMET 01 VALID 270256/270645 ENMI-
NORWAY FIR LAN AND FJORD N OF N58 S OF N62 W OF E008 LOC MOD TO SEV
TURN FCST BLW FL080. WKN.=
3. Suggested Procedures.
3.1 Currently, to ensure that these messages are promulgated, the operators carry out the following actions on messages with these problems.
If a SIGMET rejects on CoreMet with the reason in the Editor Log of "No FIR found in SIGMET/AIRMET" the following actions should be carried out.
If no ATSU indicator is present find the FIR, described in plain text within the message. Then use Doc 7910 to insert the ICAO location indicator. Then hit "CORRECT" and ensure the message is transmitted. If the message still rejects with the same reason the ICAO location indicator should be added to the FIR list in the same way as we do for "stations".
If an invalid ATSU indicator is present and it is not an obvious corruption of a known indicator then the new ATSU indicator should be inserted into the valid FIR list. Then hit "CORRECT" and ensure the message is transmitted. A problem report should be raised, and the message should be sent back to the originator with a SVC explaining that the ICAO location indicator used is unrecognised.
3.2 For the first example shown in Section 2 of this paper the location Indicator for Casablanca ACC listed in ICAO Doc. 7910 is GMMM. The operator will then insert GMMM at the beginning of the second line as shown below.
WSMC31 GMMC 020730
GMMM SIGMET 2 VALID 020730/021030
CASABLANCA FIR ISOL EMBD TS OBS ANF FCST NORTH OF 33N TOP FL300 MOV
SLW E NC =
3.3 For the second example shown in Section 2 of this paper the location Indicator for ENOR is not in Doc. 7910. The operator will then insert ENOR into the valid FIR List and resubmit the message.
4. Discussion.
4.1 Although the procedure works well for most SIGMETs encountered with this error condition the ATSU indicator usage is not so clear in some SIGMETs. Consider the SIGMET for Tel Aviv. This is routinely received with an ATSU indicator of LLBG. If a Tel Aviv SIGMET arrived without its ATSU indicator then if the operator followed the prescribed procedure then there are in fact 4 entries for Tel Aviv in Doc. 7910.
TEL_AVIV CONTROL ACC, ISRAEL LLTA
TEL_AVIV FIR/CTA/UTA, ISRAEL LLLL
TEL_AVIV/BEN GURION AIRPORT, ISRAEL LLBG
TEL_AVIV/SDE-DOV AIRPORT, ISRAEL LLSD
4.2 The Norwegian example shows another problem in that some states are not using Doc 7910 location indicators for their ATSUs at all. The proposed procedure maintains the flow of data so SIGMETs are not unduly delayed even if they have a suspect ATSU indicator. Confirmation can then be sought of the use of the indicator. It is however not ideal in that there is no global definition of SIGMET headers and their associated ATSU indicators.
4.3 It is noted that Amendment 73 of Annex 3 will include, at the request of IATA, and additional indicator preceding the FIR name on the second line of the SIGMET. This should provide a better field for the identification of FIRs than the ATSU indicator.
For example;
WSDL31 EDZF 120706
EDDF SIGMET 2 VALID 120745/121145 EDZF-
EDDF FRANKFURT FIR LOC SEV TURB ...
5. Next Steps.
5.1 Some progress is being made to ensure that an accurate list of SIGMET Headers and their associated ATSU indicators is maintained and available generally. Initially an informal suggestion was made through the EUR BMG that FASID Table Met 1B could be extended in scope in order to include the Abbreviated Heading Lines used for SIGMETs produced by each MWO. This suggestion was rejected for the following reasons.
5.2 WMO headings; are not a part of Annex 3 specifications. There is no difficulty if WMO Headers are included in guidance material (e.g. SADIS User Guide, manuals, regional guides etc.). However, regulatory material (i.e. Annexes and ANP/FASID) is another matter: a) the inclusion of frequently changing material should be avoided, since the amendment process is cumbersome (often involving a consultation with States); and b), more importantly, from the procedural point of view, it would be difficult to include any material which is outside the control of international civil aviation (i.e. ICAO and its Contracting States).
5.3 There is still however reason to be hopeful that a solution can be found. The ASIA/PAC Region are updating the ROBEX handbook in order to include the required SIGMET data. An extract from the ROBEX Handbook is provided in Attachment 1 to this paper. It is felt that Regional information of this form can be kept up to date more easily that FASID tables as it does not require the agreement of all states before amendments are issued.
5.4 The introduction of an additional FIR indicator in amendment 73 implies that the SADIS Gateway may be better employed, validating the new FIR indicator than the ATSU indicator which it does currently. It would however be sensible to delay implementation of such a change until amendment 73 has been in place for some time otherwise there is a risk of a large number of rejections when the amendment comes into force.
5.5 The question regarding validation is, 'Should the ATSU indicator continue to be validated if the FIR Indicator in the second line is to be validated'. An initial view is that as the FIR indicator will become the primary identifier of the affected FIR then there is little to be gained from the validation of the ATSU indicator further than it syntactical correctness, i.e. 4 alphabetical characters.
6. Conclusion.
6.1 In order for SIGMETs to be consistently and correctly routed to the SADIS Gateway it is important that all related regional documentation be produced in as consistent format as possible. It is strongly suggested that the model adopted by ASIA/PAC in the ROBEX handbook be produced by all ICAO Regions. It is therefore proposed that SADISOPSG produce a Conclusion encouraging the development of consistent regional meteorological guidance material in general and SIGMET header lists in particular.
6.2 SADISOPSG should be asked to consider the modification of SIGMET validation as a result of the Amendment 73 to Annex 3. If approved the SADIS Gateway provider should then be requested to provide costs associated with the modification for consideration by SCRAG.
Attachment 1
SIGMET List extracted from Draft ROBEX Handbook
MWO location / ICAO location indicator / WMO SIGMET Headings / FIR/ACC served / Remarks /WS / WC / WV / ICAO location indicator /
1 / 2 / 3 / 4 / 5 / 6 / 7 /
AUSTRALIA
ADELAIDE/Adelaide / YPRM / WSAU31 / WCAU31 / WVAU31 / YMMM
BRISBANE/Brisbane / YBRF / WSAU31 / WCAU31 / WVAU31 / YBBB
YMMM
DARWIN/Darwin / YDRM / WSAU31 / WCAU31 / WVAU31 / YBBB
YMMM
HOBART/Hobart / YMHF / WSAU31 / WCAU31 / WVAU31 / YMMM
MELBOURNE/Melbourne / YMRF / WSAU31 / WCAU31 / WVAU31 / YBBB
YMMM
PERTH/Perth / YPRF / WSAU31 / WCAU31 / WVAU31 / YBBB
YMMM
SYDNEY/Sydney / YSRF / WSAU31 / WCAU31 / WVAU31 / YBBB
YMMM
TOWNSVILLE / YBTL / WSAU31 / WCAU31 / WVAU31 / YBBB
BANGLADESH
DHAKA/Zia Intl / VGZR / WSBW20, 21, 31 / WCBW20, 31 / VGFR
CAMBODIA
PHNOM-PENH/Pochentong / VDPP / VDPP / MWO not established
CHINA
BEIJING/Capital / ZBAA / WSCI33 / ZBPE
CHENGDU/Shuangliu / ZUUU / WSCI36
GUANGZHOU/Baiyun / ZGGG / WSCI35 / ZGZU
KUNMING/Wujiaba / ZPPP / WSCI36 / ZPKM
LANZHOU/Chongchuan / ZLLL / WSCI37 / ZLHW
SHANGHAI/Hongqiao / ZSSS / WSCI34 / ZSHA
SHENYANG/Taoxian / ZYTX / WSCI38 / ZYSH
TAIBEI/Taibei Intl / RCTP / WSCI31 / WCCI31 / WVCI31 / RCTP
URUMQI/Diwopu / ZWWW / WSCI39 / ZWUQ
WUHAN/Tianhe / ZHHH / WSCI35 / ZHWH
HONG KONG/Hong Kong Intl / VHHH / WSSS20 / WCSS20 / WVSS20 / VHHK
WVSS01 / To be checked
DEMOCRATIC PEOPLE’S REPUBLIC OF KOREA
PYONGYANG/Sunan / ZKPY / ZKKK / No SIGMET issued
FIJI
NADI/Nadi Intl / NFFN / WSFJ01,02,… / WCFJ01,02,… / WVFJ01,02,… / NFFF
FRENCH POLYNESIA
TAHITI/Faaa / NTAA / WSPF21,22 / WCPF21 / WVPF21 / NTTT
GUAM (United States)
GUAM I./Agana NAS / PGUM / WSPQ31-35 / WCPN31
WCPQ31-35 / KZOA
WCPS31
INDIA
CALCUTTA/Calcutta / VECC / WSIN31 / WCIN31 / VECF
CHENNAI/Chennai / VOMM / WSIN31 / WCIN31 / VOMF
DELHI/Indira Ghandi Intl / VIDP / WSIN31 / WCIN31 / VIDF
MUMBAI/Jawaharlal Nehru Intl / VABB / WSIN31 / WCIN31 / VABF
INDONESIA
BIAK/Frans Kaisieppo / WABB / WSID23 / WCID23 / WVID23 / WABZ
DENPASAR/Ngurah Rai (Bali Intl) / WRRR / WSID22 / WCID22 / WVID22 / WRRZ
JAKARTA/Soekarno-Hatta Intl / WIII / WSID20 / WCID20 / WVID20 / WIIZ
UJUNG PANDANG/Hasanuddin / WAAA / WSID21 / WCID21 / WVID21 / WAAZ
JAPAN
TOKYO/New Tokyo Intl / RJAA / WSJP31 / WCJP31 / WVJP31 / RORG
RJTG
LAO PEOPLE’S DEMOCRATIC REPUBLIC
VIENTIANE/Wattay / VLVT / WSLA31 / WVLA31 / VLVT / Not confirmed
MALAYSIA
KOTA KINABALU/Kota Kinabalu Intl / WBKK / - / - / - / WBFC
KUALA LUMPUR/Kuala Lumpur Intl / WMKK / WSMS31 / WCMS31 / WVMS31 / WMFC
MALDIVES
MALE/Hulule / VRMM / WSMV31 / VRMM
MONGOLIA
ULAN BATOR/Ulan Bator / ZMUB / WSMO31 / ZMUB / Not confirmed
MYANMAR
YANGON/Yangon Intl / VYYY / WSBM31 / WCBM31 / VYYY / Not confirmed
NAURU
NAURU I./Nauru / ANAU / ANAU / No Information
NEPAL
KATHMANDU/Tribhuvan Intl / VNKT / WSNP31 / VNSM / Not confirmed
NEW ZEALAND
NEW ZEALAND/Wellington Intl[1] / NZKL / WSNZ21 / WCNZ21 / WVNZ21 / NZZO
WSPS21 / WCPS21 / WVPS21 / NZZC
NORTHERN MARIANA ISLANDS
(United States)
SAIPAN I. (OBYAN)/Saipan I.(Obyan) Intl / PGSN / No Information
PAKISTAN
KARACHI/Quaid-E-Azam Intl / OPKC / WSPK31 / WCPK31 / OPKR
LAHORE/Lahore / OPLA / WSPK31 / OPLR
PAPUA NEW GUINEA
PORT MORESBY/Jacksons / AYPY / WSNG20 / WCNG20 / WVNG20 / AYPY
WVNG01
PHILIPPINES
MANILA/Ninoy Aquino Intl / RPLL / WSPH31 / WCPH31 / WVPH31 / RPHI
REPUBLIC OF KOREA
INCHEON/Incheon Intl / RKSI / WSKO31 / WCKO31 / WVKO31 / RKRR
SINGAPORE
SINGAPORE/Singapore Changi / WSSS / WSSR20 / WCSR20 / WVSR20 / WSJC
SOLOMON ISLANDS
HONIARA/Henderson / AGGH / AGGG / No Information
SRI LANKA
COLOMBO/Katunayake / VCBI / WSSB31 / WCSB31 / VCBI
THAILAND
BANGKOK/Bangkok Intl / VTBD / WSTH31 / WCTH31 / WVTH31 / VTBB
UNITED STATES
ANCHORAGE/Anchorage Intl / PANC / WSPN01
WSPN31
WSPN41 / WVAK20-24 / PZAN
HONOLULU/Honolulu Intl / PHFO / WCPA31-35
WCPS31 / KZOA
(JUNEAU, Alaska) / PAJN / WSPN01 / PZAN
(KANSAS CITY/Missouri)
(National Aviation Weather Advisory Unit) / KKCI / WSPN01-15 / KZOA
??? / PAWU / WSPN47,48 / WCAK31-35 / WVAK21-25
VIET NAM
Gialam MWO / VVGL / WSVS31 / WCVS31 / WVVS31 / VVNB
VVTS
Attachment 2
Proposed Modifications to the SADIS Gateway Documentation regarding SIGMET Validation
SADIS Operations Handbook Section 2.2.4
For each individual SIGMET or AIRMET the following items shall be validated:
CCCC — The SIGMET or AIRMET, on the line following the abbreviated header, i.e. the pre-amble defined in Annex 3, must commence with a 4-letter ICAO location indicator indicating the ATSU for the FIR for which the SIGMET was issued. Validation will ensure that this field comprises 4 alphabetical characters only.
DDHHMM/DDHHMM — The SIGMET or AIRMET shall have a valid period of validity. This period of validity shall be in the format DDHHMM/DDHHMM and shall be considered valid if it meets the following conditions.
· The start of validity period shall be no more than a configurable value, T5 minutes, in the future from the current time.
· The validity period shall not exceed a configurable value of T6 minutes.
· The end of the validity period shall not be earlier than the current time.
CCCC — The SIGMET or AIRMET, on the second line following the abbreviated header must commence with the 4-letter ICAO location of the FIR for which the SIGMET was issued. A full list of valid ICAO indicators for FIRs shall be maintained on the SADIS Gateway against which the indicator can be validated.