F042-B © The MITRE Corporation This is the copyright work of The MITRE Corporation and was produced for the U.S. Government under Contract Number DTFA01-01-C and is subject to Federal Aviation Administration Acquisition Management System Clause , Rights in Data-General, Alt. III and Alt. IV (Oct. 1996). No other use other than that granted to the U.S. Government, or to those acting on behalf of the U.S. Government, under that Clause is authorized without the express written permission of The MITRE Corporation. For further information, please contact The MITRE Corporation, Contracts Office, 7515 Colshire Drive, McLean, VA 22102, (703) Initial Evaluation of URET Enhancements to Support TFM Flow Initiatives, Severe Weather Avoidance and CPDLC Fifth USA/EUROPE Seminar on ATM R&D 26 June 2003 Daniel Kirk and Richard Bolczak

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 2 User Request Evaluation Tool (URET) URET is a decision-support system for en route ATC Deployed to 6 Air Route Traffic Control Centers (ARTCCs) as part of Free Flight Phase 1 (FFP1) Will be deployed to remaining ARTCCs as part of FFP2 URET supports: –Strategic detection of Aircraft/aircraft problems Aircraft/Special Use Airspace (SUA) problems –Evaluation of user requests –Planning & coordination –Flight data managemen t

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 3 Overview This study addresses URET extensions to support –Clearance delivery via Controller Pilot Data Link Communications (CPDLC) –TFM Miles in Trail (MIT) Flow Initiative (FI) implementation –Severe weather avoidance Describes enhancements as implemented in the CAASD En Route Research Prototype Presents initial laboratory evaluation results, directions for future research

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 4 Evaluation Overview Held April and July 2002 at CAASD, with (respectively) 5 and 6 former FAA controllers Evaluations focused on –Operational acceptability and usefulness of the Concept of Use, and supporting functionality and CHI of each enhancement –Potential benefits for controllers, airspace users, and overall traffic flow Scenario used recorded data from Indianapolis En Route Center (ZID) –Selected MIT restrictions from ZID Traffic Management logs

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 5 DSR HOST HIGHER EFFECTIVE CAPACITY DSR URET VOICE RADAR ASSOCIATE RADAR DATA LINK DATA LINK REDUCED CHANNEL CONGESTION LOWER VOICE WORKLOAD FOR RADAR CONTROLLER MORE EFFECTIVE COORDINATION ENHANCED SECTOR EFFICIENCY MULTI-CHANNEL COMMUNICATIONS TFM URET/CPDLC Integration

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 6 URET/CPDLC Integration Overview This research addresses the integration of CPDLC clearances services with URET Builds on the existing URET/Host amendment capability Send Amendment to Host, then clear by voice Send Amendment to Host, then Uplink

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 7 URET/CPDLC Integration Status Information on the Aircraft List Empty Triangle: posted when a CPDLC session (communication link) is established between an aircraft and a facility Filled Triangle: posted when a sector is eligible to exchange messages with an aircraft Up-arrow: replaces a filled triangle to indicate an open uplink message for that aircraft –An up-arrow posted in orange indicates a response of UNABLE to the uplink –Selecting the up-arrow brings the Plans Display to the front with the Amendment Plan in view

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 8 URET/CPDLC Integration Integrated GPD, Altitude and Route Menus

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 9 URET/CPDLC Integration Concept of Use: Typical Sequence of Events Controller identifies CPDLC eligible aircraft with a conflict Controller uses URET’s planning tools to resolve this conflict Controller Uplinks from the display or menu –Integrated URET/CPDLC capability sends Amendment Message to the Host with an indicator that the clearance should be uplinked CPDLC message status is updated on the Aircraft List Aircraft receives CPDLC clearance message –Aircrew reviews message when workload allows

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 10 URET/CPDLC Integration Concept of Use (Concluded) Aircrew decides to accept clearance, responds WILCO –WILCO closes the message transaction CPDLC message status is updated on the Plans Display –UPLINKED is replaced by WILCO –After a parameter time (e.g., 30 seconds) the Amendment Plan grays out, and is then removed CPDLC message status is updated on the Aircraft List –Up-arrow is replaced with a filled triangle when WILCO is received

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 11 URET/CPDLC Integration Concepts for Additional Capabilities 1.Automatic formatting of altitude and speed restrictions, preferential route clearances into a CPDLC message –Uplink with a single action using the integrated CHI 2.Downlink of a Pilot Request (e.g., for a new altitude) –Triggers the creation of a (conflict-probed) URET Trial Plan for the proposed amendment –Request may be approved with a single action –If the Trial Plan has a problem, the controller can use PARR (Problem Analysis, Resolution and Ranking) to resolve Auto Replan – periodically rechecks the request

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 12 URET/CPDLC Integration Concepts for Additional Capabilities 3.Downlink of Airspace User Preferences (e.g., preferred route, altitude, speed) –With the User Preferences available, the controller and automation can better meet these preferences E.g., incorporation of User Preferences in PARR –Controller is notified when a User Preference can be granted due to the lifting of a restriction 4.Downlink of aircraft intent, e.g., Cruise speed Top of Climb, Top of Descent Planned Mach/IAS climb and descent speeds –Improved accuracy will support improved airspace utilization, particularly in the vertical dimension

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 13 Evaluation Results – URET/CPDLC Integration Potential Controller Benefits Reduced workload for issuing Trial Plans –E.g., Graphic Trial Plans, PARR resolutions, TFM reroutes –Supports flexible task sharing between the Radar (R) and Radar Associate (RA) controller Reduced switching between separate URET and CPDLC displays –E.g., routine clearances can now be input through URET Integrated data link status on the Aircraft List reduces the need to scan multiple displays –E.g., RA controller does not have to scan the Situation Display for CPDLC Eligibility indicators

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 14 Evaluation Results – URET/CPDLC Integration Potential Airspace User Benefits Improved accuracy of communications Increased use of more efficient route clearances utilizing an aircraft’s RNAV capabilities –Do not require the aircraft to fly over named fixes Increased use of efficient, strategic lateral maneuvers that do not disturb the cruise altitude of the aircraft Easier entry of complete lateral maneuvers will reduce the number of clearances not entered into the automation, improving modeling accuracy –This improved accuracy will support a more strategic operation, and improved airspace utilization

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 15 Evaluation Results – URET/CPDLC Integration Topics for Future Evaluations Data Link indicators on the Graphic Plan Display –E.g., to determine if a Graphic Trial Plan would be eligible for uplink Alert coding if a “Standby” response remains after a parameter time –Controller may need to contact pilot Revision to the previous altitude in the event of an “Unable” response –Similar to existing URET ability to reapply the previous route Integrated URET/CPDLC Transfer of Communication Additional concepts, e.g., handling of downlinked Pilot Requests

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 16 MIT FI Implementation Background MIT FIs are used to modulate traffic flow into congested areas Relayed verbally or via a paper text message Defined for a group of aircraft using criteria such as –Time of applicability –Arrival airport –Boundary or fix crossed Constraint is the number of miles between successive aircraft, e.g., 20 MIT

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 17 MIT FI Implementation Problem Statement Workload in determining applicable aircraft, particularly with multiple FIs per sector –Some aircraft in the stream may be in another sector –Spacing must be referenced to preceding aircraft Difficult to predict final sequence and spacing due to different aircraft performance characteristics, speeds, routes and/or altitudes –MIT spacing errors can be large, resulting in larger constraints “Passback” restrictions inefficient –Merging streams not coordinated –Ties can occur, gaps not utilized

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 18 MIT FI Implementation URET Display Enhancements MIT Indicators

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 19 Evaluation Results – MIT FI Implementation Potential Controller Benefits Reduced workload for identifying aircraft that are subject to the MIT FI –Particularly helpful if there are multiple MIT FIs in effect Easier identification if action is needed –Particularly when involved aircraft are merging from different streams Easier determination of the manner and magnitude of a required action Improved coordination with other sectors, due to the commonality of display information across sectors

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 20 Evaluation Results – MIT FI Implementation Potential Airspace User Benefits Reduced errors in identifying which aircraft are subject to the MIT FI Less severe, more strategic maneuvers for spacing –Supports increased capacity in the final sector where the streams must be merged A reduction in “passback” MIT constraints –To the extent that extensive coordination is not required Predicted MIT calculations accurately take into account different aircraft speeds –Reduces need to place aircraft in-trail to maintain spacing

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 21 Evaluation Results – MIT FI Implementation Topics for Future Evaluations MIT information to support Trial Planning –Spacing and sequence information in the Trial Plan results, particularly when the Trial Plan causes a sequence change Problem notification –Controller should be alerted when there is insufficient spacing –Notification using only the aircraft’s predicted MIT will not be sufficient when preceding aircraft have to be maneuvered Coordination between the R and RA controller Coordination between sectors when passback restrictions are removed

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 22 Severe weather is a major cause of delay in the NAS En route aircraft consistently avoid severe weather areas Pilots are responsible for this avoidance, but controllers typically assist when requested –Cockpit weather radar cannot “see” behind heavy precipitation –Storm movement and growth difficult to predict Severe Weather Avoidance Problem Statement

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 23 Other than the recently-added NEXRAD weather display on the R Controller display, no automation support to –Assist pilot in planning to avoid severe weather –Recognize when actions might send the aircraft into severe weather –Provide advance warning where deviations due to severe weather will be likely URET enhancements are designed to provide this support –No intent to shift severe weather separation responsibilities to the controller Severe Weather Avoidance Problem Statement (Concluded)

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 24 Severe Weather Avoidance Severe Weather Forecast Product National Convective Weather Forecast (NCWF) –Improved altitude resolution, shorter term prediction, and storm growth and decay –Utilizes NEXRAD and lightning data –Defines detection “polygons” with a maximum altitude –Minimum polygon size for NCWF is normally 520 km 2 –50 km 2 product used here (from the National Center for Atmospheric Research) –1-hour extrapolation forecast –Polygons projected 10, 20, 30, 40 minutes Products under development for:

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 25 Severe Weather Avoidance Severe Weather Notification and Display Current Plan/Trial Plan lookahead is 20/40 minutes Notification goes to controlling sector Trial Plan Current Plan

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 26 Evaluation Results – Severe Weather Avoidance Potential Controller Benefits Aircraft subject to severe weather are more easily identified –Easier to anticipate, plan for responses to pilot requests Severe weather displays support the creation of routes that avoid severe weather Less negotiation with pilots to navigate aircraft through severe weather areas Since the R Controller has a display of NEXRAD data, this display in URET supports improved Sector Team collaboration

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 27 Evaluation Results – Severe Weather Avoidance Potential Airspace User Benefits Decreased likelihood that aircraft will receive routes that encounter severe weather Ability to provide improved weather information to the pilot when requested Planning tools (e.g., severe weather display and Graphic Trial Planning) support –More efficient and effective routes around severe weather –Entry of weather avoidance maneuvers into Host, improving intent information

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 28 Evaluation Results – Severe Weather Avoidance Topics for Future Evaluation and Analysis Alert notification –Shared space for severe weather and SUA alerts Severe weather display –Labeling of polygons –Weather Motion Vectors Resolutions for severe weather avoidance –Concept of Use –Number, types of resolutions and their clearance Buffers to account for uncertainty in severe weather prediction Discussions and surveys with pilots are also underway Severe Weather SUA

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 29 January 2003 Assessment Initial assessment by members of the FAA’s Air Traffic Conflict Probe Team –Addressed enhancements for severe weather and MIT support –Held at the FAA’s Integration and Interoperability Facility (I 2 F) Similar positive results as for 2002 evaluations; for example, enhancements should –Help provide a “bigger picture” understanding when implementing MIT FIs –Help in response to pilot requests for reroutes around weather Similar suggestions for enhancements, e.g., –Controller should be alerted when there is insufficient spacing But need to consider more than just the aircraft’s predicted MIT

F042-B © 2003 The MITRE Corporation. All Rights Reserved. 30 Conclusions Results indicate that the enhancements are operationally acceptable and useful Significant benefits indicated for both the controller and the airspace user –Future work will begin to quantify these benefits Further enhancements for evaluation include –MIT information to support Trial Planning –Notification for MIT FI problems –Buffers to account for uncertainty in severe weather prediction –Resolutions for severe weather problems –Integrated URET/CPDLC Transfer of Communication