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Airborne Separation Assistance Systems(ASAS) - Summary of simulations

Joint ASAS-TN2/IATA/AEA workshopNLR, Amsterdam, 8th October 2007

Chris ShawEUROCONTROL Experimental Centre, France

European Organisation for the Safety of Air Navigation

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Contents of presentation

Introduction Radar airspace

Simulations of airborne spacing merge and remain behind in TMA

Non-radar airspace Simulations of air traffic situational

awareness for oceanic step climbs

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Introduction (1/2)

Secondary surveillance radar coverage 10,000 feet - green quadruple

Automatic Dependent Surveillance - Broadcast (ADS-B) invented 1980s.

74% of flights in Europe equipped with ADS-B Mode S extended squitter of which 79% broadcasting position (Eurocontrol, August 2007)

Benefits: Surveillance cost 1/10 of ground

based radar -> reduced navigation service charges ~30%

Wider coverage – niche areas too expensive for ground radar

Increased efficiency of flight operations enabled by airborne separation assistance system

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Introduction (2/2)

Airborne Separation Assistance System (ASAS) 1983: “Analysis of in-trail following

dynamics of Cockpit Display of Traffic Information (CDTI)”, Sorensen & Goka, NASA

2007: > 80 ASAS applications identified (Eurocontrol/FAA)

Example ASAS applications with early benefits:

Airborne spacing merge and remain behind in TMA

Airborne traffic situational awareness for oceanic step climb

© EUROCONTROL Experimental Centre

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Merge and remain behind in TMA (1/6)

Motivation Improve the sequencing of arrival flows

through a new allocation of spacing tasks between air and ground

Neither “transfer problems” nor “give more freedom” to pilots … shall be beneficial to all parties

Assumptions Air-air surveillance capabilities (ADS-B) Cockpit automation (ASAS)

Constraints Human: consider current roles and working

methods System: keep things as simple as possible

Paris Orly, 2002, source: ADP

To achieve spacing at waypoint

Merge

spacing at waypoint

Merge

To maintain spacing

Remain

To maintain spacing

Remain

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Merge and remain behind in TMA (2/6)

Development and refinement of spacing instructions and working methods

Identification of required functional evolutions (air and ground) and route structure

Aircraft under spacing

Aircraft with target selected

© EUROCONTROL Experimental Centre

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Merge and remain behind in TMA (3/6)

Assessment of feasibility, benefits and limits Representative environment

with very high traffic From cruise to final approach Nominal and non nominal

conditions (mixed equipage, go-around, emergency, radio failure, airborne spacing error, …)

Controller, pilot and system perspectives

Large panel of participants Controllers from various

ANSP (AENA, DSNA, ENAV, IAA, LFV, NATS, NAV-EP)

Pilots from Airbus and various airlines (DLH, CTN, …)

BaselineWith spacing

Distribution of inter aircraft spacing at final approach fix

9060 120 150 180

Num

ber o

f airc

raft

22

23

24

25

26

27

Baseline

Number of aircraft passing final approach fix

(period 45min)

With spacing

Flown trajectoriesBaseline

Flown trajectoriesWith spacing

© EUROCONTROL Experimental Centre

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Merge and remain behind in TMA (4/6)

EUROCONTROL-DSNA Project, October 2005 – February 2007Evaluation of operational benefits of airborne spacing sequencing and merging for Paris Arrivals

Charles de Gaulle North – partial equipage – time gain

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A new RNAV route structure?

A preliminary step to prepare implementation of airborne spacing

A transition towards extensive use of P-RNAV

A sound foundation to support further developments such as CDA (continuous descent) and 4D (target time of arrival)

Merge and remain behind in TMA (5/6)

0

20

40

60

80

100

120

0 10 20 30 40 50 60

Altit

ude

(feet

x10

0)

Distance to final approach fix (NM)

Baseline

New route structure

0

20

40

60

80

100

FinalFr

eque

ncy

occu

panc

y (%

) New route structureBaseline

Approach

© EUROCONTROL Experimental Centre

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Merge and remain behind in TMA (6/6)

Point merge preliminary fast-time simulation results (RAMS platform)

4 Initial approach fixes 1 runway 1 hour traffic ~30 aircraft with

20% heavy/80% medium mix 2 controllers Continuous descent approach

from 12,000 -> 3,000 feet Distance range 60-90 NM

Point Merge Radar Vector 400

600

800

1000

1200

1400

1600

1800

2000

2200

2400

Tot

al f

uel c

onsu

mpt

ion

in T

MA

per

airc

raft

[kg

]

© EUROCONTROL Experimental Centre

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Oceanic step climbs (1/3)

FL340

FL360

FL350

> 10 mins > 10 mins

ATSA-ITP

Criteria

• Aircraft at FL340 would like to climb …..• But standard longitudinal separation does not exist at level above • Crew request a step climb with airborne traffic situation awareness

5 mins

ASSTAR step climb with airborne traffic situation awareness

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Oceanic step climbs (2/3)

Today over North Atlantic average 0.2 step climbs per flight recorded

Fast time simulations show with airborne traffic situation awareness number of step climbs

per flight could be 2 or more.

~75% of climb requests could be satisfied immediately and at least 93% satisfied eventually.

ASSTAR fast time simulations

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Oceanic step climbs (3/3)

Costs Implementation costs per aircraft

45,000 € retrofit 35,000 € forward fit

Maintenance costs per annum 1,200 € retro fit 1,500 € forward fit

Benefits 150 Kg fuel saved per single oceanic transition 54,000 € per aircraft per year 0.6% reduction in emissions

Payback period 0.9 years retro fit 0.7 years forward fit

(Assuming 2 transitions a day and 0.5 € per kilogram)

Cost benefit analysis by BAE Systems

D5.3 (http://www.asstar.org/)