Rising to the challenge: evaluating the benefits and barriers to CCO and CDO

Picture of Vincent Lambercy
Posted by Vincent Lambercy

Continuous Climb Operations (CCO) and Continuous Descent Operations (CDO) could save 340,000 tonnes of fuel, every year, reducing Europe-wide CO2 emissions by 1.1m tonnes and cutting costs by €150m.

The benefits are appealing but as with any innovation, there are barriers to adoption. In this article, we discuss the benefits of CCO and CDO and how to overcome the challenges.

What are CCO and CDO?

Traditionally, when a plane takes off or lands, the pilot uses a stepped approach. Step-Climb sees aircraft reach a certain altitude before levelling off, cruising for a while, and then climbing again. This repeats until the plane reaches its optimal cruising altitude. Step-Descent applies the same approach to landing the plane. The process involves regular changes to throttle settings and aircraft configuration.

CCO and CDO eliminate (or at least significantly decrease) the amount of ‘levelling off’. Instead, the aircraft will continuously climb from take-off until it reaches its optimal cruising altitude. And in turn, it will continuously descend from cruising altitude (or at least from ‘top of noise’ at FL75) all the way to the runway.

The benefits of CCO and CDO

  • Helping the environment. For airports, airlines, and the wider ATM industry, reducing CO2 emissions is critical. The aviation sector is under scrutiny and accounts for about 2-2.5% of global CO2 emissions. Compared with the costs of sustainable aviation fuel and the technical challenge challenges of finding alternative power sources, implementing CCO and CDO is a relatively simple way of reducing carbon footprints. IATA reckons that operational changes like this will contribute 3% of the reductions required for the aviation sector to reach net zero.
  • Saving money and fuel. Fuel is one of the largest expenditures for airlines. In this case, profitability and environmentalism go hand-in-hand.
  • Reducing noise pollution. During CCO and CDO, airplanes stay further away from the ground for longer, compared to the typical stepped approach. An ECAC-wide study found this can reduce noise pollution in the areas around airports by 1-5dB. This leads to more desirable outdoor spaces, has less impact on surrounding wildlife, and creates a better quality of life for local communities.
  • Improving traffic flow. CCO and CDO also means airplanes spend less time in airspace. This frees up space for more departures and, in turn, improves the flow of air traffic. Faster flights, fewer delays, and a better experience for customers.

Barriers to CCO and CDO

The benefits of CCO and CDO are clear. But what obstacles are blocking the way to widespread adoption?

  • Air traffic management. As skies get busier, managing air traffic gets more complicated. There's congestion, coordination, and safety risks to consider. For Air Navigation Service Providers (ANSPs), safety always takes priority. This tends towards a degree of conservatism in the industry. And, there are change management processes in place, which take time.
  • Airspace constraints. Airspace constraints mean that CCO and CDO aren’t possible in every location. These design limitations will require airspace modernisation, updated infrastructure and more. This, of course, takes more time, planning, and money to get right.
  • Aircraft upgrades and ATM up-skilling. Making CCO and CDO possible also relies on the latest technology, both on the ground and in the cockpit. And, it requires extra training for pilots and air traffic controllers to implement. While up-skilling ATM professionals and levelling up outdated aircraft with new, innovative technology is important, it presents its own share of budget and timing challenges.

Why ANSPs should encourage CCO and CDO

At FoxATM, we are passionate about future-proofing the industry. Despite the current barriers to CCO and CDO, we see a clear path ahead. Significant CO2 reduction is vital. Fuel cost savings and ‘easy-win’ CO2 reductions are too good to ignore. Minimising noise pollution for local communities will help public perception. The positive impact is crystal clear.

Yes, ANSPs and pilots will need more training. And of course, aircraft and airport infrastructure will need updating. But all these signs point to the need for modernisation throughout ATM sector. After all, isn’t that what future-proofing is all about?