Overview of AIrspace Notam Services in the Pia Unit in the Medan Region in the Singapore Delegation Area

This research aims to review the effectiveness of NOTAM (Notice to Airmen) services in the Medan Region Aeronautical Information Services Unit (PIA), especially in the airspace area delegated to Singapore. NOTAM services in this area have complex coordination procedures and involve various agencies, including NOF Indonesia and NOF Singapore. Based on the provisions in ICAO Doc 10066 and the Letter of Coordination Agreement (LOCA), NOTAM submissions must be made at least seven days before carrying out activities. However, research results show that sending raw data by airspace user agencies is often carried out close to the implementation time, thus hampering the verification process, increasing workload, and giving rise to the potential for data errors. The research method used is descriptive qualitative through interviews, direct observation and documentation studies, with a gap analysis approach. This research concludes that delays in submitting raw data cause non-compliance with international procedures which can impact the safety and effectiveness of aeronautical information services. Therefore, it is recommended to socialize regulations, standardize raw data delivery times, and strengthen internal coordination and supervision across agencies