PBN Manual, Part A, Chapter 1 1.2.3 On-board performance monitoring and alerting 18.104.22.168 On-board performance monitoring and alerting is the main element that determines if the navigation system complies with the necessary safety level associated to an RNP application; it relates to both lateral and longitudinal navigation performance; and it allows the aircrew to detect that the navigation system is not achieving, or cannot guarantee with 10–5 integrity, the navigation performance required for the operation. Background Requirements for navigation applications on specific routes or within a specific airspace must be defined in a clear and concise manner. This is to ensure that the flight crew and the air traffic controllers (ATCOs) are aware of the on-board RNAV or RNP system capabilities in order to determine if the performance of the RNAV or RNP system is appropriate for the specific airspace requirements. Performance Based Navigation Within an airspace concept, PBN requirements will be affected by the communication, ATS surveillance and ATM environments, the NAVAID infrastructure, and the functional and operational capabilities needed to meet the ATM application. SC227-SC214 ISRA Background ICAO PBN Manual, Doc 9613
PBN Manual, Part A, Chapter 1 22.214.171.124 Flight planning of RNAV and RNP designations Manual or automated notification of an aircraft’s qualification to operate along an ATS route, on a procedure or in an airspace is provided to ATC via the Flight Plan. 1.4 Navigation Applications A navigation application is the use of a navigation specification and associated NAVAID infrastructure to ATS routes, instrument approach procedures and/or defined airspace volume in accordance with the airspace concept. An RNP application is supported by an RNP specification; an RNAV application is supported by an RNAV specification. SC227-SC214 ISRA Background ICAO PBN Manual, Doc 9613
F.1.1.1Air Traffic Control Data Link The navigation system may require the capability to support downlink requests to ATC for route changes, lateral offset, and speed and vertical clearances. Its features should support the receipt and display of corresponding clearances, plus crossing constraints, transfer of control and frequency change messages. The system should support the processing of pre-departure clearances, lateral route clearances and offset clearances, contained in uplink messages, for flight plan modification. 1.0 Introduction RNP RNAV airspace may be considered to apply to an area, route, procedure or operation using a particular RNP RNAV type. The functions are described for position estimation, path definition and steering, and user interface. 1.2.5 Navigation System Controls and Features In addition to the basic subfunctions, the navigation system will need to provide the necessary features and capabilities required to support aircraft operations in RNP RNAV airspace. SC227-SC214 ISRA Background MASPS, DO-236B
126.96.36.199.2VNAV and TOAC Operational Considerations When the system provides a performance dependent capability such as time of arrival control, the fidelity of time of arrival estimates and extent of aircraft controllability will depend upon: accurate definition of a flyable lateral and vertical path, including information for fix altitude, winds, speed, constraints, etc, specified/known aircraft performance limits The optional datalink interface described in this standard is one means to facilitate supplying additional flight path and environmental information to the system. 3.9 Datalink Interface Datalinks may be used for automated acquisition of flight plan, navigation and airplane performance related data, as well as manual requests and automatic reports. The avionics functions which provide this capability should provide not only data integrity but a level of communication performance which supports the required level of aircraft systems performance. SC227-SC214 ISRA Background MASPS, DO-236B
SC227-SC214 ISRA Background MASPS, DO-236B ISRA Related Conclusions 1.Top Level concepts, requirements and guidance are in place for the specification of RNP for airspace, routes, procedures, etc. 2.There is an operational requirement for the aircraft to monitor and alert with regard to the airspace performance requirement. 3.Top level requirements for RNP include aircraft requirements to provide for performance monitoring and alerting relative to the required performance, RNP. 4.The SC181 MASPS last published in 2003 reflects these requirements. The SC227 MASPS updates will maintain them. 5.Datalink is part of the current MASPS, and is identified as another means of creating or changing the aircraft flight plan, along with aircraft and navigation performance. 6.The gap between the datalink message set and the MASPS has been narrowed to the minimum required change, to provide navigation performance in the uplink message sets, for ATC clearances for procedures/fixes not contained in the aircraft navigation database. 7.The MASPS will also have to be made clearer with regard to the expectations on the ground system in the provision and management of the navigation performance requirements associated with these clearances.