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Challenges and operational concept development of 4DTBO in China

As one of the important modules of ICAO's Aviation System Block Upgrades (ASBU), 4D Trajectory Based Operation (4DTBO) has been recognized as a strategic approach to modernize the Air Traffic Management (ATM) system environmentally with improved flight safety and efficiency. Programs such as FAA's Next Generation Air Transportation System (NextGen) and Eurocontrol's Single European Sky ATM Research (SESAR), leading the ATM modernizations in both the US and Europe, are conducting a series of research and demonstration projects on 4DTBO Concept of Operations (ConOps) with promising results.