OpenAirInterface5G as a platform for beyond 5G/6G-NTN research

Non-Terrestrial Networks (NTN) are increasingly being considered a native component of 6G systems, enabling ubiquitous coverage, resilience, and new service classes across multi-orbit constellations and integrated terrestrial--non-terrestrial architectures. While 5G-NTN has been standardized in 3GPP Release 17 and further advanced in Releases 18 and 19, beyond-5G/6G-NTN concepts require validation using tools that bridge the gap between high-level simulation and standard-compliant, end-to-end prototyping. This paper positions OpenAirInterface5G (OAI) as a practical, standard-aligned, and modifiable baseline for early 6G-NTN research, continuing our earlier work that positioned OAI for 5G-NTN experimentation. In addition to summarizing OAI's current NTN capabilities, we provide (i) a taxonomy of 6G-NTN requirements and research gaps, (ii) a mapping of representative OAI-based 5G-NTN foundations and ongoing B5G/6G-NTN projects, and (iii) a structured mapping of representative emerging 6G-NTN research directions to relevant OAI capabilities and current limitations, outlining directions for future OAI extensions, experimental configurations, and validation approaches. These contributions are intended to give the research community a practical, open-source starting point for prototyping and validating B5G/6G-NTN concepts on standard-compliant infrastructure.