RNP AR Operation in SwedenHenrik EkstrandFlight Captain A321

Ecology & Performance Manager

Flight Operations Department

ICAO EUR PBN TF/7 Paris 03/07/2012

Quick introduction: what is RNP AR?Quick introduction: what is RNP AR?

GNSS based approach procedure initially intended to be used in a demanding environment (e.g. accessibility to airports in mountainous terrain) due to the possibilities to tailor (“curve”) the approach with high navigation accuracy.

In addition, there is a great potential to increase fuel efficiency/emissions reduction/noise mitigation in a non-demanding environment with tailored/curved approaches, i.e. track miles shortening.

Introduction to RNP AR in Sweden Introduction to RNP AR in Sweden

The two largest airports in Sweden, Stockholm Arlanda Airport ESSA/ARN and Göteborg Landvetter Airport ESGG/GOT are conducting RNP AR operation. This presentation will focus on experience gained at ESGG.

Both airports are located in non-demanding environment, i.e. a non–obstacle rich environment and all relevant runway ends are equipped with ILS, CAT I, CAT II and CAT III.

Both airports are using P-RNAV STARs (open/closed loop).

The main objective at both airports is to gain environmental benefits (emissions/noise).

Göteborg Landvetter AirportGöteborg Landvetter Airport

Second largest airport in Sweden.

Single RWY operation 03/21 (3300 m).

Average of 230 movements a day.

Typical European medium density airport.

Mixed mode operation in terms of airborne navigation capabilities, (RNAV, non-RNAV, RNP).

Göteborg Landvetter Airport-the VINGA projectGöteborg Landvetter Airport-the VINGA project

A SESAR project called VINGA, conducted in the frame of AIRE II (Atlantic Interoperability Initiative to Reduce Emissions), a joint programme between SESAR and FAA was used to develop four RNP AR procedures and one RNP transition to ILS. The project VINGA ran in 2010-2011.

Two of the RNP AR approaches were not used during the project.

The project included the following partners:

supported by:

RNP AR approaches used during VINGARNP AR approaches used during VINGA

RNP AR approaches not used during VINGARNP AR approaches not used during VINGA

Göteborg Landvetter AirportGöteborg Landvetter Airport

The high-level objectives of the VINGA project during the arrival phase were to validate: From an ATM perspective, how additional procedures would fit into the existing ATC system, since it included the challenge of handling aircraft with different navigation capabilities and usage of newly developed STARs and RNP AR approaches.

The potential of reduced CO2 emissions and noise from the en-route phase of the arriving flight into Göteborg Landvetter Airport, through the approach, landing, and surface phase until parking on the gate, by using a state-of-the-art validation aircraft and using best practice.

Lateral trajectory RNP AR vs. P-RNAV-ILS ESGG21

A typical VINGA flight – usage of RNP AR approachesA typical VINGA flight – usage of RNP AR approaches

300 km prior to landing:Initial contact with Malmö ATCC. Pilot requests RNP AR approach. The ATCO acknowledges the request and forwards it via the ATC system. ATCO gives aircraft routing direct to OSNAK or KOVUX.

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Aircraft leaves ToD at optimum point to conduct CDO.

Hand-over to approach sector – no verbal coordination.

Pilot receives inbound clearance. Information about flight to Göteborg TMA silent via the Eurocat 2000 E system.

Malmö

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2.

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RNP AR approaches used in various traffic situationsRNP AR approaches used in various traffic situations

P-RNAV-ILS

RNP AR

RNP AR approaches used in various traffic situationsRNP AR approaches used in various traffic situations

RNP AR

P-RNAV Non - RNAV

ATCO confidence in the technologyATCO confidence in the technology

All arriving RNP AR approaches to RYW21 during the VINGA

project. High navigational accuracy gives the ATCO confidence in

the RNP technology.

RNP AR operation from an Airspace Users perspectiveRNP AR operation from an Airspace Users perspective

Track adherence-RNP AR approachesTrack adherence-RNP AR approaches

17 m ≈ 0,01 NM

1 NM = 1852 m0,1 NM = 185,2 m0,01 NM = 18,52 m

Track adherence-RNP AR approachesTrack adherence-RNP AR approaches

17 m ≈ 0,01 NM

Fuel analysis of the arrival phaseFuel analysis of the arrival phase

The aim of the analysis was to evaluate the VINGA RNP AR arrivals from a fuel efficiency perspective compared to the non-VINGA P-RNAV arrivals (i.e. “normal” arrivals).

Questions to be answered were:

Is the fuel consumption lower for the VINGA arrivals compared to the non-VINGA arrivals (P-RNAV-ILS)?

If yes, how large is the fuel saving for the different arrivals?

How much of the potential savings is related to lateral aspects and how much is related to vertical aspects?

A relative method for analysing the arrivals was developed and implemented by Novair based on aircraft derived data and the airframe manufactures performance tables.

Fuel analysis resultsFuel analysis results

The VINGA-flights (RNP AR) for both runways resulted in reduced fuel consumption compared to the corresponding non-VINGA-flights (P-RNAV STAR’s + ILS).

For RWY21, the total fuel saving was measured to 90 kg.

71 kg related to lateral aspects (10,9 NM shorter flight distance)

19 kg related to vertical aspects (unconstrained RNP AR)

For RWY03, the total fuel saving was measured to 22 kg.

22 kg related to lateral aspects (2,5 NM shorter flight distance)

6 kg related to vertical aspects (unconstrained RNP AR)

The two RNP AR approaches not being usedThe two RNP AR approaches not being used

One of the procedures was rejected by the Swedish CAA due to the implementation of a new P-RNAV SID/STAR system at the adjacent city airport.

The other one was not used due to differences in interpretation of the ICAO Document 9905 between members of the VINGA project and the Swedish CAA.

The issue with the turnThe issue with the turn

It was decided to use statistical MET data, obtained via soundings (MET balloons), for the last 10 years. Statistical temperature was also used.

The high level objective was to enter the turn (GG990) in a clean aircraft configuration, 16 NM from threshold.

A speed constraint below 225 KIAS, would had forced the aircraft/FMS to start the deceleration premature, i.e. well before GG990, thus generating more drag and more noise.

The issue with ICAO Doc 9905The issue with ICAO Doc 9905

ICAO Doc 9905

Section 3.2.2.3.

The question was

how to interpret

this section.

Average wind when RWY21 in useAverage wind when RWY21 in use

Approximate position with the highest tailwind component

Deceleration Segment

Average wind

direction

RF leg

Statistical meteorological dataStatistical meteorological data

Average wind between 4000-5550 ft MSL in the sector 225º-294º when the surface wind favours RWY21 (outlier values included): 258º/24 knots.

Based on this momentarily average tailwind, the turn could be done with 225 KIAS and 20° bank angle, which correspond to a clean aircraft configuration.

To cater for 95% of all wind scenarios (2· standard deviation (2σ)), 42 knots of tail wind would need to be considered momentarily, corresponding to 22,5° bank angle.

Statistical meteorological data and aircraft performance Statistical meteorological data and aircraft performance

For the turn starting at GG990 (given radius)

24 knots of tailwind = 20° bank angle

42 knots of tailwind = 22,5° bank angle

95 knots of tailwind = 30° bank angle (aircraft limitation)

≈ 110 knots of tailwind = unable to maintain RNP 0,3 with 30° bank angle (dashed black corridor)

R

R + RNP

R + 2RNP

RNP AR ImplementationRNP AR Implementation

Conclusions-VINGA Final ReportConclusions-VINGA Final Report

The VINGA project showed that mixed-mode operation is achievable in a typical medium-sized European airport in the day-to-day operation.

RNP AR operation is seen as an enabler to conduct environmentally efficient operations in the TMA due to flight path shortening and the possibility to tailor the trajectory (e.g. fuel saving and mitigating noise in the vicinity of the airport).

A close dialogue and collaboration with the CAA is the vital key for success. Development and changes require close collaboration between ANSPs, Airspace Users, industry, airports and regulatory authorities; the latter must be included in any process at an early stage and have an active role to play.

The VINGA project was successful, one of the reasons was that all different stakeholders were working in partnership.

Full report available via the SJU website.

http://www.sesarju.eu/sites/default/files/documents/reports/AIRE_-_Vinga.pdf?issuusl=ignore

Stockholm Arlanda Airport-RWY26Stockholm Arlanda Airport-RWY26

The procedure to RWY26 was developed in the frame of the AIRE II project Green Connection.

Validated during spring 2012.

The procedure is in normal use today.

Stockholm Arlanda Airport-RWY26Stockholm Arlanda Airport-RWY26

Stockholm Arlanda Airport-RYW26Stockholm Arlanda Airport-RYW26

Stockholm Arlanda Airport-RWY01RStockholm Arlanda Airport-RWY01R

Developed during the AIRE I project MINT.

First flown in June 2009 by Novair (A321).

Used to circumnavigate a noise sensitive community south of the airport.

In limited use today.

Questions?

henrik.ekstrand@novair.se