Faculty of air transport engineering the department of «air navigation systems»

CHAPTER I. IMPLEMENTATION OF THE NEW STANDART ROUTE AND ITS INFLUENCE.

1. 
   Implementation of RNAV.
   

1. 
   RNAV concept.
   

The concept of airspace can be considered as a general vision or master plan for a particular airspace. Based on specific principles, the concept of air space is aimed at achieving specific goals. The concepts of the airspace should be detailed to a certain extent in case changes need to be made to the airspace in question. For example, detailed information on the organization and management of the airspace may be provided, as well as tasks performed by various stakeholders and users of the airspace. The concepts of airspace may also specify various specific tasks and responsibilities, the mechanisms used, and the relationship between man and machine.
Strategic objectives are the driving force behind the overall vision of the airspace concept. Typically, these goals are determined by the users of the airspace, the air traffic management (ATM), airports, as well as environmental policy and public policy. The function of the airspace concept and the concept of
Figure 1. Strategic objectives to airspace concept.
flight operations and is compliance with these requirements. The strategic objectives, which in most cases are the defining factors of the concept of airspace, are flight safety, capacity, efficiency, access and the environment. As shown in examples 1 and 2 below, strategic objectives can lead to changes in the concept of airspace.
Example 1.
Safety: The design of RNP instrument approach procedures could be a way of increasing safety
Capacity: Planning the addition of an extra runway at an airport to increase capacity will trigger a change to the airspace concept
Efficiency: A user requirement to optimize flight profiles on departure and arrival could make flights more efficient in term of fuel burn.
Environment: Requirements for reduced emission, noise preferential routes or continuous descend/arrivals/approaches (CDA), are environmental motivators for change.
Access: A requirement to provide an approach with lower minima than supported by conventional procedures, to ensure continued access to the airport during bad weather, may result in providing an RNP approach to that runway.
Example 2.
Although GNSS is associated primarily with navigation, GSS is also the backbone of ADS-B surveillance application. As such, GNSS positioning and track-keeping functions are no longer “confined” to being a navigation enabler to an airspace concept. GNSS, in this case is also an ATS surveillance enabler.
The cascade effect from strategic objectives to the concept of airspace imposes requirements on various "implementation tools", such as communications, navigation, ATS surveillance, air traffic management and flight operations. It is necessary to define the navigation functional requirements, but now within the context of performance-based navigation (see chapter 2 of Part B of this volume). These navigation functionalities are formalized in the navigation specification, which, along with the navigation tools infrastructure, provides a specific navigation application process. As an integral part of the airspace concept, navigation applications are also relevant to communications, ATS surveillance, ATM, ATC facilities, and flight operations. The c oncept of air space combines all these elements together into one single whole.

Figure 2. Relationship: PBN and airspace concept

The above approach is based on the principle of "top-down": it starts at the general level to determine the specific requirements, i.e. how the CNS / ATM will meet this concept and its flight concept.
Defines the role that each implementation tool will play in the overall concept. No "implementation tool" can be developed in isolation, i.e. communication, ATS surveillance, and navigation implementation tools must form a single whole. This can be illustrated by an example.
The existing concepts of airspace in the aerodrome area, which include arrival and departure, are provided by RNAV application processes. They are currently used in the European (EUR) region and in the United States of America. The RNAV used in European airspace in the area of the airfield is known as P-RNAV (Precision RNAV). As of the date of publication of this manual, the application process used in the United States of America in the aerodrome area, formerly known as US RNAV Type B, is aligned with the PBN concept and is now called RNAV 1. Basic-RNP 1 is designed primarily for use in non-radar airspace in the low-traffic aerodrome area. In the future, new RNP applications are expected to be developed for both route airspace and airfield areas.
The approach concepts cover all instrument approach sections, i.e. initial, intermediate, final, and second-round approach. They will increasingly require RNP specifications with a navigational accuracy of 0.3 m. miles – 0.1 m. miles or lower. Typically, this phase of flight is characterized by three types of RNP application processes: new runway schemes that have never been used for instrument flight schemes, schemes that either replace existing instrument flight schemes or serve as backup schemes for existing schemes based on other technologies, and schemes designed to improve access to the airport in difficult environmental conditions.