In 2019, President Joko Widodo announced the relocation of Indonesia’s capital from Jakarta to the North Penajam Paser and Kutai Kertanegara Regencies in East Kalimantan. This decision was made in response to long-standing issues plaguing Jakarta, such as overpopulation, declining quality of life and environment, and poverty. To accommodate the relocation of the capital to Nusantara Capital City (IKN), the government has planned the development of transportation infrastructure, including an airport rail system. This decision is based on efforts to facilitate accessibility to IKN and address the distance barrier between IKN and Sultan Aji Muhammad Sulaiman Sepinggan (SAMS) Airport in Balikpapan, which serves as a vital air gateway to IKN. However, the current Electric Rail Train (KRL)-based airport trains operating in Indonesia are deemed unsuitable for the SAMS-IKN airport rail route, given the specific track specifications set by the government. Therefore, this research aims to address this issue by designing an airport rail that is suitable for the SAMS-IKN route, with specifications that allow for optimal and efficient operation, as well as to become a proud icon of IKN transportation. It is expected that this research will make a significant contribution to developing an airport rail that can facilitate better accessibility to Nusantara Capital City. This study will use data collection methods including expert interviews, field observations, and existing studies to obtain the necessary primary data. Secondary data will be obtained through previous research, government policies, journals, and literature relevant to the research topic.