GOF3 addresses the need for safe, scalable and integrated low and very low-level mixed airspace operations, aiming to increase capacity through innovative communication, navigation and surveillance and U-space solutions. Solution 1, targeting TRL7, develops GNSS-redundant electronic conspicuity and resilient data links, integrating multiple surveillance and e-conspicuity systems with mobile networks to provide situational awareness and conflict detection without costly infrastructure. Solution 2, targeting TRL6, extends U-space services to crewed and uncrewed aircraft beyond U-space airspace, offering traffic information, decision support and conflict management, laying the foundation for scalable beyond-visual-line-of-sight (BVLOS) operations. Building on SESAR initiatives and aligned with the Digital European Sky, NATO and EDA guidelines, GOF3 combines high-TRL technologies, operational concepts and safety assessments, validated through simulations, live demonstrations and stakeholder feedback.