AMOSSG/5-SN No. 23

7/4/05

AERODROME METEOROLOGICAL OBSERVING SYSTEMS STUDY GROUP (AMOSSG)

FIFTH MEETING

Montreal, 11 to 14 April 2005

Agenda Item	5:	Aerodrome observation requirements
5.2:	Capability of automatic observing equipment to meet aeronautical requirements and the use of automated equipment during operational hours
5.3:	Use of remote sensing techniques

THE USE OF FULLY AUTOMATIC OBSERVING SYSTEMS DURING OPERATIONAL HOURS

(Presented by Akoa Benoit Okossi)

SUMMARY
This paper outlines the problems related to the implementation of the use of fully automatic observing systems during the operational hours in AFI region specially in developing countries and invites AMMOSSO/5 to agree that the fully automatic systems must not replace human observers in all IACO regions until present and recent weather and TREND forecast be automated with a satisfactory accuracy.

1.	INTRODUCTION

1.1	The summary of AMOSSG/4 conclusions suggests the following items: The group agreed on the progress being made in the ability of automatic observing systems to meet the full aeronautical requirements for all meteorological elements except for present and recent weather. The introduction of the remote sensing such as lightning detection and weather radar were noted to have been effective in addressing previous concerns. It was also noted that several States including Australia, Canada, Finland and the United States already use fully automatic observing systems during the operational hours at some aerodromes, and these States use fully automatic observing systems to support aerodrome forecast (TAF) production. However, it agreed that Annex 3 requirements for present weather can not currently be fully met by automation.

2.	DISCUSSION

2.1	Actions related to automatic observing systems

2.1.1	The implementation of the Automatic Observing Systems in the AFI Region specially in the ASECNA area requires to take into account the climate hazards occurring in these regions for equipment design. The atmosphere for African sahelian countries is characterized by dust that can cause the misworking of the sensors of automatic equipments. The RVR sensors installed in some aerodromes of ASECNA do not work well when they are covered by haze or humidity.

2.1.2	The maintenance of the automatic equipment for aerodrome meteorological observations is a very important topic to deal with in the implementation of these equipments in the developing countries if a continuous observation has to be ensured.

2.1.3	The highly recorded cost of these automatic equipments for the African countries has been noted by ASECNA at the AMOSSG/4 Meeting.

2.1.4	According to FASID AFI Table MET 1A, the aerodrome meteorological observations from the main aerodrome of AFI area must be completed by a TREND forecast. The automation of the TREND has not been yet discussed in the implementation of Aerodrome automatic meteorological observing systems.

3.	CONCLUSION

3.1	The design of the sensors of automatic equipments must take into account the climate hazards in Africa. Considering the limited financial means of some developing countries, this implementation can not be done in an accelerated manner.

3.2	Considering above, it is proposed that messages from fully automatic systems should not be reported during the operational hours without any human action.

4.	ACTION BY THE GROUP

4.1	The group is invited to:

a)	note information include in this paper; and

b)	recommend that the fully automatic systems should not replace the human observers in all ICAO regions until present and recent weather and TREND forecast be automated with a satisfactory accuracy.

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