_CAASD

Bridging the Gap between Air Transportation System Simulations

and Environmental Models for NextGen Benefits Assessment

Presented at leNS, April 26 2012

Anuja Mahashabde, William Baden, James

DeArmon, Jennifer Harding, Justin Field,

Fred Bankert, and Koffi Amefia

Disclaimer: The contents of this material reflect the views of the author and/or the Director of the Center for Advanced Aviation

System Development. Neither the Federal Aviation Administration nor the Department of Transportation makes any warranty or guarantee, or promise, expressed or implied, concerning the content or accuracy of the views expressed herein. MITRE

F03E-B12-001

Overview

• Motivation

• Research Challenges

• Methodology

• Preliminary Results

• Summary

• Next Steps

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Motivation

• Environmental considerations

gaining more importance (ICAO,

EPA, EU ETS, NEPA, etc.)

• FAA Research, Engineering, and

Development Advisory

Committee (REDAC) FY2012

recommendations on

incorporating environmental

issues in research and planning

efforts

• FAA Destination 2025 and

NextGen goals for sustainable

aviation growth

• Congress • EPA • Local Communities • I nternational Stakeholders

, I ,

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How can we assess tradeoffs among operational and environmental goals?

DELAY

ENVIRONMENTAL IMPACTS

Noise, Fuel burn, Emissions

WORKLOAD

Increasing need for an integrated analysis capability for

assessing NAS-wide operational and environmental

performance

4

Operational changes include PBN procedures,

Equivalent Visual Operations, Adjacent Center

Metering, etc. MITRE

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Bridging the gap between operational

and environmental models

Fast-time, NAS-wide I simulation tool that models response to I

rc_o_ng_

e_s_tio

_n

---========-1 I I n put

systemwideModeler I Flight Tracks & ......-�

I Operations

Research

Objective

Outputs include 4-D

flight trajectories

impeded by congestion

Integrated FAA noise and emissions model

Aviation Environmental

Design Tool

Output

Noise Fuel Burn & Emissions

Source:

hUp:llwww.faa.gov/abouUoffice_or

g/headquarters_offices/apl/researc

h/models/historyl20101

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Key Challenges

Harmonizing Trajectory Representation Between Simulation and Environmental Tools

Terminal Area

ARRIVALS

systemwideModeler . � tracks ;:::;'

/

Problem: Low-resolution terminal area trajectories Solution: Radar tracks or procedures are appended to en route trajectories

6

En route Delay Absorption

VECTORS

�'�'-� , '-

, '-c • t )

HOLDS

{�� �) Problem: Simulations identify where en route delays occur, and not how they are accommodated Solution: Delay absorption through vectors and holds MITRE

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systemwideModeler-AEDT Connectivity

systemwideModeler

• Flight Trajectory

• Delay taken

• Aircraft Type

• 010 Pair

...... - -

Research Focus

Terminal

area

En route

delay

absorption

• En route trajectory modification

• Arrival and departure paths from

TRACON library

• Environmental study input

generation

• - AEDT

• Noise

• Emissions

• Fuel burn

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Terminal Area: TRACON Path Library

• Objective: Replace simulation terminal area trajectories to enhance trajectory resolution

• Approach: Creation of a repository of suitable flight paths to append on to simulation trajectories

- Radar tracks based on present day operations - Performance Based Navigation (PBN) procedures

- Backbone tracks derived from present day operations

• Selection of a path from the library is driven by study requirements:

- Smooth transition between en route and terminal domains - lateral and vertical profile match

- Delay predicted in the terminal area

- Technology/equipage

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TRACON Path Library - Radar Tracks

• Should adequately represent average annual conditions at airport

• Focus on Core 30 airports

• Stability of Coefficient of Variation (std/mean) tracked

• -100 sample days found to be sufficient to capture variability

• Validation conducted for ATL, BOS, BWI

- CV comparison with one year of radar data

- Levene test for equality of variances

- Geographic visualization • On-going work on TPL fleet

mix assessment

o Most CVs stabilize in -100 sample day

o 20 40 60 80 100 120

Cumulative Number of Sample Days

Flight tracks for ATL arrivals: 100-day sample (blue

color) and 365-day sample (green color) MITRE 9 F03E-B12-001

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En Route Delay Absorption

• systemwideModeler predicts delay along the flight trajectory

Total amount of delay in units of time

- Location along trajectory

• We modify trajectories to introduce vectors and holds for environmental modeling

• Assumptions - Delay maneuvers do not account for

ATe constraints - separation standards, restricted airspace, etc.

- Simplified turn angle constraints introduced

- Speed change not incorporated as a delay absorption maneuver yet

- Vectoring is the preferred method for absorbing delay

- Holding used when delay exceeds the maximum delay that can be absorbed through vectoring

/

( T---

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En Route Delay without Holding

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En Route Delay with Holding

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Preliminary Performance Results

'" "

LAX '\--------""r

De cv vectors for ATL arri

• Sample 5 airport analysis in AEDT

• Further testing needed to refine performance modeling and make

modifications to delay absorption mechanisms as needed

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Page 14

Summary

• This work enables assessment of tradeoffs

between NextGen operational and environmental

objectives at the NAS-wide scale

• Differences in trajectory representation pose key

challenges to bridging the gap between

simulation and environmental tools

• Methodology presented for harmonizing

trajectory definition between systemwideModeler

and AEDT

- Terminal area path library

- En route delay absorption through vectors and holds

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Next Steps

• Expansion of the TRACON path library to include

PBN procedures, treatment of non-Core 30

airports, and fleet mix validation

• Further refinement and testing of delay

absorption algorithms

• Continuing work on improving study generation

process

• On-going discussions on a sample NAS-wide

application of this analysis capability

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Questions?

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