Wayne Farley's Aviation Blog - Air Traffic Management

Performance-Based Navigation (PBN) defines performance requirements for aircraft navigating on an ATS route, terminal procedure or in a designated airspace. It provides a way forward in addressing today’s - and tomorrow’s - aviation system capacity, efficiency, environmental and safety issues. PBN is ICAO’s effort and objective to redefine the regional differences of various Area Navigation (RNAV) and Required Navigation Performance (RNP) specifications into a globally harmonized set of PBN applications. PBN’s RNAV and RNP components provide a foundation for aviation system evolutionary developments such as SESAR and NextGen.
To better understand the concept of PBN, here’s a look at the events leading up to PBN, and the benefits associated with the use of PBN.
The global aviation community is facing significant challenges. As demand for air transportation services increase, States are faced with finding solutions to safely increase capacity, efficiency, and access, e.g. to terrain challenged airports. These constraints are largely a result of reliance upon conventional ground-based navigation aids (e.g., VOR, NDB, ILS), which limit routes and procedures to the physical locations of ground-based navigation aids. These ground-based systems have served the aviation community well since inception; however, they do not permit the flexibility of point-to-point operations available with PBN to meet the challenges of today and the future.
ICAO has adopted PBN to address these challenges. Through the application of Area Navigation (RNAV) and Required Navigation Performance (RNP) specifications, PBN provides the means for flexible routes and terminal procedures. The illustrations depict the constraints associated with conventional, ground-based sensor specific routes/procedures and the flexibility and benefits of performance-based, non-sensor specific navigation (both RNAV and RNP).
PBN is helping the global aviation community reduce aviation congestion, conserve fuel, protect the environment, reduce the impact of aircraft noise and maintain reliable, all-weather operations, even at the most challenging airports. It provides operators with greater flexibility and better operating returns while increasing the safety of regional and national airspace systems.

The Benefits of PBN

• Provide Environmental Benefits
  • Reduces emissions by saving fuel. 3.15 kg of CO2 emissions are eliminated for every 1 kg of fuel savings achieved through shorter and vertically optimized PBN flight paths. IATA estimates that globally, shorter PBN routes could cut CO2 emissions by 13 million tonnes per year. Additionally, PBN provides a mechanism for optimized profile descents that allow aircraft to descend from high altitudes to the airport at minimum thrust settings.
  • Reduces noise pollution. Consistent, precise paths can be routed to avoid noise sensitive areas. Noise levels can often be reduced through use of optimized profile descents, which allow lower, quieter thrust levels.
• Improve Safety
  • Reduces the risk of Controlled Flight Into Terrain (CFIT) accidents by providing a very precise lateral and vertical flight path.
  • Provides consistent, predictable and stabilized approaches. Aircraft arrive at the runway aligned with the centerline, in the same configuration and at the same speed every time.
  • Reduces diversions caused by adverse weather conditions, enabling aircraft to reliably access airports with lower visibility restrictions.
• Improve Operating Returns
  • Reduces fuel waste through shorter flight tracks, optimized profile descents and fewer diversions. Enables more direct and closely spaced parallel tracks en route for increased fuel efficiency and reduced flight time variance. More efficient departure operations enable fuel savings from decreased taxi/ground waiting lines.
  • Creates new market opportunities by providing safe access to terrain and weather challenged destinations. PBN also provides a path for airline growth as emissions caps are implemented around the world.
  • Provides a degree of precision approach capability without the investment required for expensive ground-based infrastructure.
  • Improves customer satisfaction/customer loyalty by allowing airlines to more consistently access airports serviced at higher on-time rates.
• Increase Airspace Capacity
  • Increases traffic capacity through more efficient routes and smoother flows. Reduces airspace conflicts between adjacent airports and prohibited or special use airspace.

Global Support
At the 2007 36th International Civil Aviation Organization (ICAO) General Assembly, States agreed to Resolution A36-23, which urges all States to implement routes and airport procedures in accordance with the ICAO PBN criteria. In support of the resolution, ICAO Regional PBN Implementation Task Forces were established to coordinate the regional implementation programs.
Key industry players established a Global PBN Task Force which affirms the industry’s commitment to safety, access, capacity, efficiency and environmental sustainability of the air transportation system. It recognizes PBN as a catalyst for these improvements, and declares its support of PBN according to the ICAO provisions and established timetable.