real-time trajectory predictor calibration through...
TRANSCRIPT
Real-Time Trajectory Predictor
Calibration through Extended
Projected Profile (EPP) Down-Link
Jesper Bronsvoort & Greg McDonald
Airservices Australia
Mike Paglione & Christina M. Young
FAA
Joachim Hochwarth
GE Aviation Systems LLC
FAA/EUROCONTROL ATM R&D Seminar
Lisbon, Portugal, June 2015
Jean Boucquey
EUROCONTROL
Eduardo Gallo
Boeing Research & Technology Europe
Overview
1. Trajectory Synchronisation
2. Data-Link Standards
3. Aircraft Intent Generation based on EPP
4. Test Scenario
5. Real-time Calibration based on EPP
6. Conclusion
Trajectory Synchronisation
• Flight Management System (FMS) and ground-based Decision
Support Tools all have own version of the trajectory to be flown.
• The objective of air-ground trajectory synchronisation is to produce
trajectories in these disparate systems, increasing the likelihood of
flying the planned conflict-free and business preferred trajectories1.
1 KLOOSTER, J., TORRES, S., CASTILLO-EFFEN, M., SUBBU, R., KANMER, L., CHAN, D., & TOMLINSON, T. (2010). TRAJECTORY SYNCHRONIZATION AND NEGOTIATION IN TRAJECTORY
BASED OPERATIONS. PROCEEDINGS OF THE 29TH DIGITAL AVIONICS SYSTEMS CONFERENCE, SALT LAKE CITY, UT.
Data-Link Standards
• Data-link to synchronise trajectory information essential to TBO
• Currently (limited) trajectory information can be obtained by ATC from FMS via FANS-1/A as ADS-C Intermediate Projected Intent (IPI)
• Recently the Extended Predicted Profile (EPP) trajectory down-link standard was created by RTCA and EUROCAE to support air-ground trajectory synchronisation (DO-350/ED-228). EPP extends and improves IPI.
1990 2000 1980 2010 2020
Future Air Navigation
Systems 1/A
Aircraft
Communications
Addressing and
Reporting System
(ACARS) Aeronautical
Telecommunications
Network (ATN)
Link 2000+ ADS-C EPP
CPDLC & RNAV & ADS-C (IPI)
CPDLC
IPI-EPP Comparison Item Intermediate Projected Intent (IPI) Extended Predicted Profile (EPP)
General Maximum number of trajectory
change points (TCPs)
10 128
Maximum look ahead time 0-255 mins 15-1200 mins
TCP
Estimated
State
TCP location Yes (sequence of bearing and
distance from start point)
Yes (Latitude and longitude)
TCP altitude Yes Yes
TCP time Yes Yes
TCP speed No Yes
TCP
Specification
TCP waypoint name (if appl.) No Yes
TCP type specification No Yes
Level change, e.g. Top of Climb
(TOC) / Top of Descent (TOD)
Yes Yes
Lateral change Yes Yes
Speed change start Implementation dependent (at least
one of two provided)
Yes
Speed change end Yes
Crossover No Yes
Waypoint Depends if coincides with
lateral/vertical/speed change
Yes
Turn
Geometry
Fly-by turn radius No Yes
Fly-over turn radius/radii No No
Supports Radius to Fix (RF) legs No Yes
Add. Data Gross mass No Yes
Problem Solved?
• “The EPP unambiguously defined speed intent data (including speed
changes), and allowed for accurate reconstruction of the lateral path,
except for fly-over waypoints as the current EPP standard does not
include turn radii for these manoeuvres.” 2
• Problem of trajectory synchronisation solved?
2 BRONSVOORT, J., MCDONALD, G., HOCHWARTH, J, & GALLO, E. (2014). AIR TO GROUND TRAJECTORY SYNCHRONISATION THROUGH EXTENDED PREDICTED PROFILE (EPP): A PILOT
STUDY. PROCEEDINGS OF THE 14TH AIAA AVIATION TECHNOLOGY, INTEGRATION, AND OPERATIONS CONFERENCE, ATLANTA, USA
Test Scenario 1
• Brisbane (YBBN) to
Melbourne (YMML)
• RNAV SID RWY01
• Published Route
• RNAV STAR with RNP
transition to RWY34
• B737-500
• Cost Index 60
YBBN
YMML
Process
GE FMS
Simulator Flight Plan
EPP
Translator
EPP to
AIDL
Translator
Dali
Trajectory
Predictor
Ground
Trajectory
• GE FMS Simulator
• Boeing Aircraft Intent Description Language (AIDL)
• Airservices Dali Trajectory Modeller (BADA4)
SID
STAR
Reference
Trajectory
????
IPI to
AIDL
Translator
IPI
Results Scenario 1
2.2NM
Test Scenario 2
• Brisbane (YBBN) to
Melbourne (YMML)
• RNAV SID RWY01
• Published Route
• RNAV STAR with RNP
transition to RWY34
• B737-500
• Cost Index 60
• Derate take-off & climb
YBBN
YMML
Results Scenario 2
7.5NM
Test Scenario 3
• Brisbane (YBBN) to
Melbourne (YMML)
• RNAV SID RWY01
• Published Route
• RNAV STAR with RNP
transition to RWY34
• B737-500
• Cost Index 60
• Derate Take-off & Climb
• 5% Drag Factor
YBBN
YMML
Results Scenario 3
15NM
2500ft
Problem
• EPP provides the ability to synchronise lateral, speed and altitude
intent.
• But no
• ‘thrust intent’ as climb rating, anti-ice and high-idle.
• unknown aircraft performance characteristics such as drag factor.
• Lots of variables!
• Inclusion of all into EPP impractical
• bandwidth requirements.
• Confidential or proprietary information.
Calibration
• Torres et al (2011)3
• EPP was used to derive average vertical rate between EPP
points to update ground performance tables
• Kinematic approach
• Only works for single down-linked instance of EPP –
synchronises trajectory
• What if we could use EPP to synchronise the trajectory prediction
process rather than a single trajectory?
3 TORRES, S., KLOOSTER, J., HOCHWARTH, J., SUBBU, R., CASTILLO-EFFEN, M., & REN, L. (2011). TRAJECTORY SYNCHRONIZATION BETWEEN AIR AND GROUND TRAJECTORY
PREDICTORS. PROCEEDINGS OF THE 30TH DIGITAL AVIONICS SYSTEMS CONFERENCE, SEATTLE.
Calibration (2)
Initial
Conditions
Predicted
Trajectory
Aircraft
Intent
Aircraft
Performance
Model (APM)
Weather
Model (WM)
Trajectory Engine (TE)
Trajectory Predictor
• EPP allows for practically unambiguous description of aircraft intent
• Weather models can be accounted for by two-stage approach4
• Kinetic calibration of aircraft performance model
APMEPPTASTAS DTcgVm sin
4BRONSVOORT, J. (2014). CONTRIBUTIONS TO TRAJECTORY PREDICTION THEORY AND ITS APPLICATION TO ARRIVAL MANAGEMENT FOR AIR TRAFFIC CONTROL. SUBMITTED TO
DEPARTAMENTO DE SEÑALES, SISTEMAS Y RADIOCOMUNICACIONES. ESCUELA TÉCNICA SUPERIOR DE INGENIEROS DE TELECOMUNICACIÓN, UNIVERSIDAD POLITÉCNICA DE MADRID,
MADRID.
Calibration (3)
• Nominal mass from EPP
• Nominal A/C performance from BADA
• Optimization process to find c for
each EPP segment
EPP
APM
EPPTASTASm
DTcgV
sin
EPP1
EPP2
Dali Trajectory Predictor
Results – Nominal with Calibration 1.1NM
NOMINAL EPP TRAJECTORY
ALTITUDE BAND [FT]
C [-]
0 2127 1
2127 3466 1.00
3466 9292 0.97
9292 9661 1.03
9661 10000 1.04
10000 10355 1.00
10355 10896 1.01
10896 23013 0.99
23013 25452 0.98
25452 32000 0.99
Results – Derate with Calibration 1.0NM
EPP TRAJECTORY WITH DERATE
ALTITUDE BAND [FT]
C [-]
0 2113 1
2113 3044 0.72
3044 7480 0.72
7480 7958 0.78
7958 8991 0.82
8991 10000 0.83
10000 11156 0.84
11156 21768 0.96
21768 25452 0.97
25452 32000 0.99
Results – Derate & Drag Factor (Calb) 1.3NM
EPP TRAJECTORY WITH DERATE & DRAG FACTOR
ALTITUDE BAND [FT]
C [-]
0 2116 1
2116 3017 0.74
3017 7327 0.70
7327 7827 0.77
7827 8781 0.76
8781 10000 0.82
10000 11228 0.82
11228 21174 0.91
21174 25452 0.90
25452 32000 0.88
Application
Ground Trajectory based on
nominal EPP with derate
Application
Trial trajectory for 280KIAS
without calibration
Application
Trial trajectory for 280KIAS
with calibration
Confirmed by new EPP
down-link
Application
Confirmed by new EPP
down-link
Conclusion
• Not all variables that impact the air-ground trajectory synchronisation
process are included in the current EPP definition (DO-350/ED-228).
• It is impractical to include all these variables into a trajectory down-
link definition, therefore real-time calibration will be essential for
effective trajectory negotiation and management.
• With a single EPP down-link, the trajectory prediction process can be
synchronised through a calibration function, ensuring high accuracy
‘what-if’ trajectories and thereby anticipating the FMS behaviour upon
changes in aircraft intent.
Thank you
Flying has torn apart the relationship of space and time: it uses our old
clock but with new yardsticks.
— Charles A. Lindbergh.
Back-Up Slides
AIDL Generation Segment AIDL
Constant
Speed
HS(CAS/M) Speed targets provided EPP by trajectory change
points. TL(MCMB)
Acceleration EL(ESF) Acceleration segment fully defined by speed change
start and end point in the EPP. Energy share factor
be determined.
TL(MCMB)
Segment AIDL
Cruise HS(M) Altitude and speed provided by EPP trajectory
change points. TOC and TOD trajectory change
points identified. 128 points visible.
HA(PRE)
Segment AIDL
Pseudo-idle at
constant speed
HS(CAS/M)* Speed targets provided EPP by trajectory change
points. Altitude profile well established with all
relevant trajectory change points present in the EPP.
HPA(GEO)
Deceleration SL(CAS/M)* Deceleration segment defined by speed change start
and end point in the EPP. Speed law to model
deceleration can be determined from these EPP
points.
HPA(GEO)
• Climb
• Cruise
• Descent