Continuous Climb Operation (CCO) and Continuous Descent Operation (CDO) are aircraft operating techniques supported by airspace and procedure design and facilitated by air traffic control clearances for executing a flight profile optimized to the operating capability of the aircraft. CCO enables departures to reach an initial cruise flight level at the optimum airspeed and engine thrust settings, resulting in reduced fuel burn and emissions and less noise. Similarly, CDO facilitates an optimum descent profile for the arrivals with low engine thrust settings and a low drag configuration, thus reducing fuel burn and emissions, and noise during descent. Hence CCO/CDO provides an efficient flight path for departures and arrivals.
The efficient Flight Path concept through Trajectory-based Operations (TBO) is enabled by Performance-based Navigation (PBN). PBN also supports the application of ASBU modules that contribute to significant efficiency, capacity and environmental benefits, such as: B0-CDO and B1-CDO – Continuous Descent Operations (CDOs), B0-CCO – Continuous Climb Operations (CCOs). The application of CCO and CDO leads to many environmental benefits as aircraft can operate without altitude restrictions during the departure or arrival phase and thus optimize their flight profile resulting in less noise and reductions in fuel burn and emissions.
Implementation of CCO/CDO at high-density airports is one of the priority areas for APAC States as per the APAC Air Navigation Plan. In order to help states in CCO/CDO implementation, a session was dedicated to CCO/CDO implementation in the last PBNICG/7 held in 2020. In this session, apart from the status update from states, one presentation each from China and India about the implementation methodology, challenges, and their mitigation and benefits derived from CDO and CCO was discussed.
Based on the feedback from the states a webinar on CDO/CCO has been scheduled for September 2021 to help states in CCO/CDO implementation. In the webinar, States having experience of CCO/CDO implementation will be encouraged to share their experience in terms of challenges and mitigation for other states to learn. ICAO office will highlight the requirements of CCO/CDO implementations and benefits it could accrue to the states.
For implementation of CCO, ICAO Doc 9993 may be referred to, and for CDO, ICAO Doc 9931. Details about the next webinar on CCO/CDO are available here.