The AIRNOISE-UAM Tool and
its Application to ATM-X
Jinhua Li, Hok Ng and Yun Zheng
NASA Acoustics Technical Working Group and Urban Air Mobility
Meeting, November 4
th
, 2020
Overview
• AIRNOISE and AIRNOISE-UAM
• Verification with AEDT software
• Use case examples
2
Overview
• AIRNOISE and AIRNOISE-UAM
• Verification with AEDT software
• Use case examples
3
AIRNOISE Tool
• AEDT is the FAA-required tool for fleet noise assessment at the airport.
• Purpose of AIRNOISE:
• Optimize flight trajectories for noise mitigation
• Fast-time analysis of noise impacts
• Benefits of AIRNOISE:
• High fidelity - Built on the widely accepted SAE-1845 acoustic methods that were
also used in AEDT software
• Fast time - Compute single event in milliseconds; core written in C language; also
has a CUDA C version with GPU parallel computing
• Scalable - Modular design, scalable for NAS wide noise assessment
• Flexible - Integrate with other tools and software
4
AIRNOISE-UAM Tool
AIRNOISE-UAM AIRNOISE
Operation mode Fixed-wing operation mode using
fixed-point profile
Fixed-wing operation mode
Acoustic database Gen-1 NPD data from RVLT NPD data from AEDT
Study area Urban area Airport area
User interface Interactive GUI created using
Python with Bokeh library
Interactive GUI created using
Python with Tinker library
Core computing
language
C C, CUDA C
• List of major changes and/or improvements from AIRNOISE
5
Overview
• AIRNOISE and AIRNOISE-UAM
• Verification with AEDT software
• Use case examples
6
V&V with AEDT: Methods
• The predicted Sound Exposure Level (SEL) values from AIRNOISE-UAM
are verified with those from the FAA’s AEDT tool using the same
inputs of flight profiles and Gen-1 NPD data provided from RVLT team
• A full flight profile is further divided into smaller flight segments at
different vehicle operation modes (climb, cruise, descend, hover,
vertical up and down) for verification. The SEL values from each flight
segment are compared at the same set of receptor locations.
7
V&V with AEDT: Vehicle Performance Profile
0
200
400
600
800
1000
1200
0 20000 40000 60000 80000 100000 120000 140000
Altitude (ft)
0
20
40
60
80
100
120
0 20000 40000 60000 80000 100000 120000 140000
Speed (knot)
Flight Trajectory profile Speed profile
8
Horizontal Hover
Vertical Hover
Vertical UP
Vertical Down
AEDT
AIRNOISE
-UAM
V&V with AEDT: Segment Comparison
9
V&V with AEDT: Segment Comparison (cont.)
Cruise Segment Climb SegmentDescend Segment
10
V&V with AEDT: Full Profile Comparison
Average receptor SEL difference Maximum receptor SEL difference
0.03 dBA 1.29 dBA
AEDT
AIRNOISE-UAM
Differences of predicted SEL values from AEDT and AIRNOISE-UAM at 400,000 receptor
locations are summarized below:
• Noise contours of an east-west straight route
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V&V with AEDT: Full Profile Comparison (cont.)
• Noise contours of a X2 route with SEL values >= 55 dBs and 5dB increasement
AEDT AIRNOISE-UAM
12
Overview
• AIRNOISE and AIRNOISE-UAM
• Verification with AEDT software
• Use case examples
13
NASA’s UAM Airspace Sub-Project Goals
• Enable UAM Maturity Level-4
(UML-4) operational density and
complexity, with 100s of
simultaneous operations in a
metropolitan area managed
through an UTM-like (Unmanned
Aircraft System Traffic
Management) architecture and
paradigm with third-party
provided airspace and air traffic
management services
14
UAM Noise Management Research Objectives
• Phase 1-FY20 Research
• UTM for UAM focus on service-
oriented architecture and
information exchange
• Predict noise-sensitive airspace
regions for UAM route planning
15
• Phase 2-FY21 Research
– Define airspace requirements to enable UML-4 op density and complexity
– UAM noise modeling and management
• Assess UAM fleet noise given vehicle performance models, baseline airspace
structure, and traffic demand
• Incorporate research-validated details and requirements into the UAM ConOps
for support refining airspace structure and flight rules and procedures for
mitigating noise impacts
USE CASE A: Noise Exposure Map
• Noise exposure map and noise compliance program are developed by
airport operators to the FAA for noise compliance planning at that
airport
• A noise exposure map is a scaled geographic depiction of an airport, its
noise exposure contours, and noise sensitive facilities and land uses in
the surrounding area.
16
Noise Exposure Map for UAM
• Airspace and flight plan data are from
NASA’s UAM X2 engineering simulation. It
consists of 16 routes from 15 vertiports
near Dallas-Fort Worth (DFW)
• Local environment and community data
are obtained from open sources.
(Left) Flight routes and vertiport locations near DFW
17
18
Route –
N-UAM200
Worship – Church
of the incarnation
School – Notre
Dame School of
Dallas
Vertiport – KDT4
Hospital – Baylor
Scott & White
Medical Center
Residential - # of
household = 411
45dBA*
50dBA
* DNL contours are predicted using AIRNOISE-UAM under the
assumption of 600 day-time operations.
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X2 Noise Impact Analysis
route name
# of affected
household*
# of affected
population
# of affected
schools
# of affected
place of worships
# of cities
crossed
N-UAM352
136887 275864 10 16 5
N-UAM200
132795 277388 6 13 3
N-UAM217
89570 224622 4 6 6
N-UAM402
87441 220280 5 7 7
N-UAM285
63867 154225 1 0 11
N-UAM150
62590 166868 7 2 11
N-UAM100
61348 164175 7 1 11
N-UAM268
58068 134935 0 0 8
U-UAM200
49642 115027 3 3 5
U-UAM150
48840 115256 10 4 8
N-UAM251
43626 106278 2 5 4
U-UAM300
37552 99822 4 2 4
U-UAM250
37539 103583 0 5 4
N-UAM452
22861 58514 1 0 2
N-UAM302
21160 57018 1 2 2
*The affected residences and noise sensitive facilities is defined as those within the 1 mile distance to
the flight route or departure/arrival vertiports.
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X2 Noise Impact Analysis (cont.)
route name
Controlled Airspace Crossing Through
U-UAM150 ['DALLAS CLASS B', 'DALLAS-FT WORTH CLASS E5']
U-UAM200 ['DALLAS CLASS B', 'DALLAS-FT WORTH CLASS E5', 'DALLAS ADDISON AIRPORT CLASS D']
U-UAM250 ['DALLAS CLASS B', 'DALLAS-FT WORTH CLASS E5']
U-UAM300 ['DALLAS CLASS B', 'DALLAS-FT WORTH CLASS E5']
N-UAM100 ['DALLAS-FT WORTH CLASS E5']
N-UAM150 ['DALLAS-FT WORTH CLASS E5']
N-UAM200 ['DALLAS CLASS B', 'DALLAS-FT WORTH CLASS E5']
N-UAM217 ['DALLAS-FT WORTH CLASS E5']
N-UAM251 ['DALLAS CLASS B', 'DALLAS-FT WORTH CLASS E5']
N-UAM268 ['DALLAS CLASS B', 'DALLAS-FT WORTH CLASS E5', 'DALLAS ADDISON AIRPORT CLASS D']
N-UAM285 ['DALLAS CLASS B', 'DALLAS-FT WORTH CLASS E5']
N-UAM302 ['DALLAS CLASS B', 'DALLAS-FT WORTH CLASS E5']
N-UAM352 ['DALLAS CLASS B', 'DALLAS-FT WORTH CLASS E5']
N-UAM402 ['DALLAS-FT WORTH CLASS E5']
N-UAM452 ['DALLAS CLASS B', 'DALLAS-FT WORTH CLASS E5']
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USE CASE B: Noise-aware Route Planning
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Noise-aware Route Planning Algorithm
23
KCAT
KDT4
X 2
Minimum
Population-to-go
X 2
Min.
Populat
ion
Min.
Population
Noise-aware Route Planning Algorithm (cont.)
24
KCAT
KDT4
X 2
Minimum
Population-to-go
to KDT4
X 2
Min.
Populat
ion
Min.
Population
Un-useable
Airspace for
UAM
Summary
• A new UAM noise prediction tool “AIRNOISE-UAM” was developed.
• The AIRNOISE-UAM tool was verified with AEDT tool using the Gen-1
NPD data in collaboration with RVLT team. Results show that
predicted sound exposure level values from AIRNOISE-UAM match
those from AEDT.
• We demonstrated two use cases of AIRNOISE-UAM under NASA’s
ATM-X project:
• Build noise exposure maps for noise compliance planning and visualization
• Develop optimization algorithms for noise-aware flight route planning
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