Performance Based Navigation (PBN) Lags Behind Schedule

ICAO’s target of having satellite-based approaches at every qualifying airport by the end of 2016 will not be met at the current rate of deployment, industry experts say. Only a few years into the ICAO time line, deployment already is well behind schedule. There would have to a significant acceleration in the rollout of these procedures for the ICAO goal to be met.

Broadly, performance-based navigation (PBN) encompasses a shift from current ground-based navigation aids emitting signals to aircraft receivers, to ‘in-aircraft’ systems that receive satellite signals that meet specific accuracy and integrity requirements combined with the Global Positioning System (GPS) to advise the aircraft’s position.

This performance-based navigation (PBN) initiative stems from an ICAO resolution in 2007, reinforced by another resolution last year. The requirement is for every instrument-capable runway to have satellite-based approach procedures with vertical guidance (APV) and lateral guidance. APV falls under the broad definition of required navigation performance (RNP).

The first deployment target was for approaches to be installed at 30% of airports globally by the end of 2010, but to date this has occurred at just 15%. The next milestones call for 70% of the procedures to be implemented by 2014, and 100% in 2016.

Director general of the Civil Air Navigation Services Organization Graham Lake, says “We are not really seeing the sort of progress we’d like, it is not a question of funding, because PBN “is about implementation of existing technologies.”

Robert Kennedy, a PBN advisor, agrees that ICAO members are “struggling to achieve” the PBN milestones. But while the current deployment level is low worldwide, the rate of introduction is picking up, Kennedy says. Despite these signs of improvement, “we all realize we are at the tip of the iceberg [with deployment] and there is so much more work to be done.”

Steve Fulton, technical fellow with GE Aviation’s PBN Services says, "there are more than 1,500 runways in North America that are candidates for APV approaches, and so far about 30% have them. Latin American deployment is in the 10%-20% range, but no other region has reached 10% deployment. Showing aviation authorities that implementing APVs is not difficult or prohibitively expensive will help spur deployment. Gaining airline support for PBN is crucial. New aircraft already are equipped, and ICAO offers support to regulators that want to begin implementation. However, the lack of qualified procedure designers is problem.

In the U.S., for example, many carriers are disenchanted with APV initiatives, Fulton says. Survey responses show that airlines often do not use APV approaches because many offer only limited efficiency gains. The airline calls for added value are “not unrealistic or out of line with the ICAO goals,” says Fulton. “If [APVs] continue to not meet expectations, [the ICAO initiative] will fail.”