RNP for EveryOne

Implementing RNP Workshop – Workshop – Toulouse 4-5 October Octo ber 2005

RNP for Everyman Jeremy Davidson

 ATM Drivers

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Improved Safety

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Increased Capacity

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Greater Efficiency

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Reduced Environmental Impact

 ATM Drivers

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Improved Safety

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Increased Capacity

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Greater Efficiency

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Reduced Environmental Impact

Navigation Enablers - Now Certification Operational Approval  Airspace Design Procedure Design

TGL 10   AMC 20XX (near approval) approval)   AMC 20XZ (mature (mature draft)  PANS-ATM  TGL 10 - based route spacing  PANS-OPS 

RNAV(GNSS)  RNP (1 - 0.3) with RF legs  RNAV/Baro VNAV  APV I/II  ILS/MLS/GLS 

PANS-OPS vs PANS-ATM 1. Procedure design addresses obstacle clearance, takes direct account of: •

Navigation System Error (NSE)

•

Flight Technical Error (FTE)

and adds a buffer for any other errors. 2. Airspace design addresses procedural separation/route spacing and takes direct account of: •

NSE

•

FTE

•

Traffic direction and density

•

Workload

•  ATM environment •

Blunder 

 ATM Drivers - Safety 

Standard operations wherever possible 

Standard design and charting criteria

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Standard certification and approval requirements

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Standard ATC and pilot procedures

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 Acceptable workload (pilot and controller)

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 Action to reduce CFIT 

Replace circling approaches with straight-in approaches

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Replace conventional NPA with RNAV approaches

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Review operations that require special approval

Safety – Current Capabilities

Standard design, charting, certification and approval criteria in place for: 

En-route – B-RNAV and P-RNAV

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Terminal – P-RNAV and RNP 1 – 0.3

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 Approach – RNAV(GNSS), RNP 0.3 and APV I/II

Safety - Basic GNSS NPA Design

3NM 1.2NM

IF

FAF

1 NM

Safety - APV I/II Design

IF

FAF

Safety - Basic GNSS vs APV I/II

3NM 1.2NM

IF

FAF

1 NM

Safety -Basic GNSS vs RNP 0.3

RNP 0.5 + buffer  3NM

RNP 0.3 + buffer  1.2NM

RNP 0.3 + buffer  1 NM

4 x RNP 0.3 + 2 x 0.2NM Buffer 

ROC

Safety - Are the Buffers Necessary? 

TGL 10, AMC 20XX and AMC 20XZ Integrity Requirements: “on procedures notified exclusively for RNAV equipped aircraft, the  probability of displaying misleading navigational or positional information  to the flight crew shall be remote .”

An airborne safety objective of Remote is an alleviation to the current  guidelines of AMJ 25-11, which specifies Extremely Remote for the  departure, arrival and approach phases of flight. 

In TGL 10 and AMC 20XX: “This alleviation recognises that the PANS-OPS procedure design, and PANS-RAC air  traffic separation criteria, account for and accommodate these type of aircraft and their  system integrity in current airspace. Furthermore, conservative safety margins are used in  the design of (P-)RNAV procedures such that the risks are not increased above those  currently experienced .”

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For P-RNAV and Basic GNSS NPAs, the buffers are used to justify the integrity alleviation.

Safety - Are Buffers Necessary in RNP? 

In AMC 20 XZ : This alleviation recognises that not only is the RNP system design evaluated  consistent with known industry and regulatory system safety assessment  practices but is now augmented with a comprehensive assessment of system  performance assurance , that is unique for RNP. Both are subject to the same objective of Remote such that the results could  be combined in an overall system assessment after accounting for any  conditional or common elements. However, to avoid confusion with existing  assessment practices, a combined assessment is not required. The result is  that the safety assurance provided greatly exceeds that of conventional  navigation systems. The RNP operational safety objective is further enhanced through the PANS-  OPS procedure design, and PANS-RAC air traffic separation criteria that  account for and accommodate these type of aircraft and their system integrity  in RNP terminal area arrival, departure, and approach procedure airspace.

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How much enhancement is expected from the PANS?

Safety - Specials Special approvals are given for specific operations where standard criteria cannot be applied.

Steep approaches/off-set approaches/landing on beaches… etc

Specials – RNP Solutions

D

 ATM Drivers - Capacity Maximise airspace and runway usage. Current ATC options: Fixed route/procedure structure  – „best‟ route spacing (P-RNAV) 8 -10NM  Radar vectoring  – best lateral separation 3 – 5NM  Vertical separation  – 1000ft 

There are no international route spacing standards for RNP ≤1

 ATM Drivers - Efficiency Efficient flight requires optimum profiles, direct routing and no delays. Careful airspace design based on RNAV.  Revised ATC procedures supported by ATC tools. 

(Better tools will allow aircraft to stay on profile longer.)

No mixed mode operations – all aircraft meet the same navigation standard.  All operators follow standard procedures. 

Capacity & Efficiency - Current Capabilities

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B-RNAV allowed some choke points to be removed.

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P-RNAV allows optimised routing in enroute and terminal airspace.

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RNP with fixed radius transitions (en-route and terminal) could help further.

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These are only of benefit if the whole aircraft population in the sector can participate.

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Mixed mode operations not acceptable.

Capacity and Efficiency - Operational Requirements

Capacity & Efficiency - Close to the runway Parallel Operations

Converging Operations

Adjacent Airport Operations

Single Runway Access

 9 

Airport A 36L

36

36

Airport B

 All these RNP examples address traffic separation on final/missed approach. Experience with parallel approach operations has showed that these are very site specific and difficult to generalise.

36L

 ATM Drivers - Environment

RNAV functionality is the key to: 

Optimising profiles to minimise environmental impact

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Keeping routes clear of sensitive areas

Future Improvements 

Certification Operational Approval  Airspace Design Procedure Design

 AMC 20 XZ Rev1   

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Fixed radius transitions (en-route), RNP holding, RTA

PANS-ATM 

RNP-based system separation (lateral, vertical and time)

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PANS-OPS (and associated manuals) 

Revised criteria:  

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 ATC Tools 

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RNAV(GNSS) / Change to RNP 0.3 RNP(AR) (0.3 – 0.1)

Track integrity monitoring

Data link  

State Intent

Future Improvements - RNP(AR)

Latest deliberations by OCP: 

New RNP criteria to be developed

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To be known as RNP (Authorisation Required)

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RNP(AR) to be based upon FAA AC 90 Public RNP SAAAR and FAA Order 8260.51

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Expect RNP(AR) criteria to be published in a separate manual, referenced in PANS-OPS.

RNP 0.3 and proposed RNP(AR) 0.3

RNP 0.5 RNP 0.5 + buffer 

4 x RNP 0.3

RNP 0.3 RNP 0.3 + buffer 

RNP 0.3 RNP 0.3 + buffer 

4 x RNP 0.3 + 2 x 0.2NM Buffer 

ROC

RNP 0.3 and proposed RNP (AR) 0.1

RNP 0.1

RNP 0.1

RNP 0.5 + buffer  RNP 0.3 + buffer 

4 x RNP 0.1

RNP 0.3 + buffer 

4 x RNP 0.3 + 2 x 0.2NM Buffer 

ROC

 APV I/II and proposed RNP(AR) 0.1

RNP 0.3 RNP 0.1

RNP 0.1

ILS Cat I and proposed RNP(AR) 0.1

RNP 0.1

RNP 0.1

Note that the ILS caters for early, unguided missed approaches

RNP(AR) – Outstanding Issues

In AC 90 Public RNP SAAAR: The probability of the aircraft exiting the lateral and vertical extent of  the obstacle clearance volume shall not exceed  10-7  per approach, including the approach and missed approach. This requirement as  a numerical value does not imply that the objective should be met  by the aircraft navigation systems alone through numerical methods. A qualitative combination of the aircraft navigation systems, other  aircraft systems, and operational procedures and mitigations  is  adequate.

„2XRNP‟ is not sufficient in itself - it all depends on the „mitigations‟.

CONCLUSION 

Standardisation breeds success.

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The design criteria available today can be used by a large percentage of the existing fleet.

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There are benefits that can be gained immediately.

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The future will bring international standards for lower  RNP values and improved functionality. However  there are still issues to be addressed.

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RNP (AR) will be beneficial at difficult airports but will probably only be of value in densely populated airspace when all aircraft have the same authorization.

With RNP  – almost anything is possible !

Questions?