Supply, Delivery, Installation & Testing of Meteorological System and Accessories

Overview

Mahavir Shree International Pvt. Ltd. carried out the supply, delivery, installation, integration, testing, and commissioning of Aviation Weather Observation System (AWOS/Meteorological Information System) equipment across 18 domestic airports in Nepal, for the Civil Aviation Authority of Nepal (CAAN)/CNAD, under contract CAAN/CNAD/NCB-01/076/77. The work covered met parks at runway thresholds and ATC tower MET displays, built to ICAO Annex 3, ICAO Annex 14, and WMO requirements, enabling Aerodrome Flight Information Service (AFIS) operations with real-time wind, pressure (QNH/QFE), temperature, and humidity data. The project was completed on 4 October 2020, with a project duration of 1 year, 4 months, and 18 days.

Airports covered (18): Rajbiraj, Doti, Balewa, Safebagar, Rumjatar, Rara, Chaurjahari, Meghauli, Salle, Nepalgunj, Bharatpur, Jumla, Chandragadhi, Dhangadhi, Biratnagar, Janakpur, Simara, and Surkhet.

Scope & Deliverables

• Standards followed: ICAO Annex 3 (Meteorological Service for International Air Navigation); ICAO Annex 14, Vol I, Ch. 6 (Type B low-intensity obstacle lighting); WMO guidelines for wind gust calculation, averaging periods, and sensor compliance; ISO 16622 (ultrasonic anemometer); EMC EN/IEC 61326-1; sensors calibrated by accredited laboratories with calibration certificates delivered.
• Met park civil and structural works at each runway threshold: 4 m x 4 m chain-link fenced compound with lockable gate and 0.5 m elevated platform topped with 50 mm PCC; 10 m frangible, self-supporting, tiltable rectangular truss aluminum mast (UV-protected, red/white, modular in 3 or more sections, rated for 134 mph or greater wind load); GI mounting pole, Ø2", 3 m, with IP-rated weatherproof enclosures; ICAO Type B low-intensity red LED obstruction light (12 VDC, ≥30 cd, ≤5 W, IP68, die-cast aluminum, pipe-mounted).
• Earthing and lightning protection: lightning arrester ≥7 ft, 14 mm copper rod; copper strip ≥20 mm x 3 mm with gas/chemical welded joints; two copper plates, 680 x 680 x 3 mm; ground resistance <15 Ω with separated earths; executed per DWG-02.
• Sensors and data acquisition: ultrasonic wind sensor with bird protection (range 0–65 m/s, resolution 0.01 m/s, accuracy ±0.1 m/s; direction 0–360°, resolution ≤1°, accuracy ±2°; response ≤260 ms; IP66/67 stainless steel; 3 s, 2 min, and 10 min averages with WMO gust calculation; ISO 16622 compliant); pressure sensor (capacitive/aneroid/silicon absolute, 500–1100 hPa, resolution ≤0.1 hPa, accuracy ±0.25 hPa, stability ±0.1 hPa/year, QNH/QFE calculation, RS-232/485/422/SDI/analog interface, 12 VDC, EN 61326); combined temperature/RH sensor with radiation shield (−10 to +60 °C, accuracy ±0.2 °C; 0–100% RH, accuracy ±2% RH; dewpoint computed; IP65, 12 VDC, EN 61326); data logger for edge acquisition, processing, storage, and transmission with WMO time-averaging and gust computation; surge protection devices (SPD) for sensitive electronics.
• ATC tower MET display: single-screen, multicolor, PC-based display running licensed software; parameters shown with required averaging and min/max — wind speed (instant/3 s, 2 min avg, 10 min avg, gusts), wind direction (instant/3 s, 2 min avg, 10 min avg, min/max, graphical rose), temperature, relative humidity, dew point, and pressure (QNH/QFE); Ethernet 10/100 and RS-232/485 interfaces; 220 VAC ±10% and 24 VDC power; ATC console, desktop, or wall mounting; EN 61326-1 EMC compliant.
• Solar power at met parks: 12 V/100 Wp mono-crystalline panels (TUV IEC 61215 & 61730) on 2 m aluminum poles; VRLA maintenance-free battery, 12 V, 100 Ah @ C10, approximately 1200 cycles at 60% DoD; MPPT charge controller, 12 V system, 25 A ±5%, −5 to +55 °C, with SC/OL/RP/HVD/LVD and surge protections; DC cabling sized to load and distance.
• Fiber data link between met park and tower: single-mode SC media converters (1310 nm, up to 40 km, Tx ≥ −5 dBm, Rx ≤ −25 dBm, RJ-45 and fiber ports, 12–48 VDC input, UL/EN, reverse-polarity and power-line protection); single-mode G.652.D optical fiber cable (≥6 cores, OD ≥8.0 mm, crush rating 2000 N, bend radius ≥20D, attenuation ≤0.38 dB/km at 1310 nm and ≤0.25 dB/km at 1550 nm); 90 cm deep trenching with protective mesh, 1" PVC and ≥1.5" HDPE conduits, and "below fiber cable" markers at ≥25 m intervals and bends; 600 x 600 mm hand holes with 400 x 400 mm concrete covers, concrete PEG markers (2 ft high, ~100 cm from hand hole center, ~100 m spacing), and 2 m fiber slack coiled in each hand hole; existing OFC reused where feasible.
• Road transportation of equipment from CAAN/CNAD to each of the 18 sites, including handling and staging.
• Site surveys with CNAD at all airports; site-specific shop drawings for civil, structural, electrical, and fiber routes (DWGs 01–03) approved by CNAD before execution; test plans and procedures submitted and approved at least one week before Site Acceptance Testing (SAT); SAT conducted with CNAD engineers, with earthing resistance (<15 Ω) recorded and calibration certificates verified.
• Documentation delivered: system block diagrams, wiring diagrams, user/operational manuals, calibration certificates, as-built drawings, test reports, and spares list.
• Training: 5 working days of local technical maintenance and operational training at CAAN/CNAD, led by the OEM's technical specialist, at MSI's cost.

Outcome

Meteorological systems were installed, tested, and commissioned across all 18 domestic airports, delivering standardized real-time wind, pressure (QNH/QFE), temperature, relative humidity, and dew-point data at ATC tower consoles for AFIS operations. The systems run on stand-alone solar power with earthing, lightning, and surge protection, and are linked to the tower displays over protected fiber optic cabling. MSI provided a 1-year warranty on all system components with software updates during the warranty period, and guaranteed maintenance support availability for a minimum of 10 years post-commissioning, together with spare parts and calibration support programs. CAAN/CNAD was responsible for site selection, land matters, field facilitation, and customs support. Local technical personnel at CAAN/CNAD were trained on system operation and maintenance.