Pilot training courses for flying on PBN navigation systems

For on-board area navigation equipment (RNAV), as for all navigation devices, accuracy requirements are set. These requirements are enshrined in the PBN concept, and are expressed in the form of so-called navigation specifications RNAV and RNP and can be established for airways, aerodrome schemes, or for entire regions.

At the end of the 1980s, ICAO issued a manual on RNP (Required Navigation Performance) (not to be confused with the RNP specification of the PBN concept). The main focus of the RNP manual was on the accuracy of onboard and ground equipment. For RNP-1 and 4, there was a requirement for monitoring current navigation performance, as well as issuing warnings. Accuracy requirements were expressed in nautical miles of linear lateral evasion, for example, RNP-1 means that, with a probability of 0.95, linear lateral evasion should remain within ± 1 nautical mile relative to the axis of the route (the probability of 0.95 corresponds to two RMS errors). It is also said that for 95% of the time the flight should take place within one nautical mile from the axis of the route. This does not mean that the remaining 5% can fly outside the route. Under the route is meant any line of the route, including the promptly specified, and not just the published ATS route.

Since the ICAO document had the status of recommended practice, many states set their own requirements. In essence, these requirements corresponded to the RNP, but there were no requirements for monitoring the current navigation performance with the onboard equipment. The only requirement was the accuracy of navigation, expressed in nautical miles. This was due primarily to the features of the navigation equipment in use at that time.

In the United States, the RNAV-5 and RNAV-1 standards were in force, and in Europe as a whole, similar B-RNAV and P-RNAV. B-RNAV or Basic-RNAV requirements corresponded to a lateral accuracy of 5 nautical miles, and P-RNAV or Precision-RNAV - 1 nautical mile. BRNAV requirements were introduced in the European Region in 1998. The PRNAV rules were intended for use in the aerodrome area.

The next step was the concept (PBN - performance based navigation) or performance-based navigation, which combined and systematized all pre-existing navigation accuracy requirements.

The PBN concept implies a more flexible approach, with the following requirements for equipment: accuracy, integrity, operational readiness, continuity and functionality. From the point of view of practical application of PBN, only the accuracy and functionality of the system are important, the remaining parameters are interesting to the developers of the equipment and those who allow the system to operate in accordance with one or another specification. In principle, it is not very important what means will be used to fulfill the conditions set out in one or another navigation specification. Each specification assumes the choice of navigation sensors, i.e. The specified accuracy can be ensured using, for example, DME / DME, and GNSS. The refusal to assign requirements for a particular equipment allowed us to optimize the structure of the airspace.

There are two types of specifications: RNP and RNAV, the main difference of which is the requirement to monitor and alert the crew in case of failure to maintain specified characteristics for the RNP specifications.

The PBN concept in perspective implies a transition to RNP specifications, which will allow for a higher density of the route network in the context of a growing traffic volume.

The two main aspects of the PBN application are the requirements set forth in the relevant navigation specification, as well as the infrastructure of the navigation aids (both terrestrial and satellite), which ensure the operation of the system.

The navigation specification is a set of requirements for aircraft equipment and flight crew, which are necessary to ensure the process of zonal navigation within the established airspace.

Both for the RNP and RNAV designations, the number following it (where it appears) indicates the accuracy of horizontal navigation in nautical miles, with a probability of 0.95, the aircraft must be within the specified limits.

Each specific aircraft is certified for compliance with certain navigation specifications, depending on its equipment and characteristics of the navigation system. Flight crew members must also receive appropriate training.

Due to the fact that the navigation specification is a set of requirements where accuracy is not the only criterion, an aircraft that has access, for example, to RNP-1, may not meet the less stringent requirements of RNAV-5.

Today, the pre-existing requirements of PRNAV, BRNAV, US-RNAV are replaced by PBN specifications. In accordance with the concept, each specification has its own purpose.

PBN specification information is encoded in coded field 18 of the flight plan, so ATS personnel are notified that an aircraft on a particular flight is allowed to navigate according to a specific specification.

For training questions, please contact us by email: trto@skyavia.com.ua or by phone +38 044 337 17 18.