1 

National Aeronautics and Space Administration 

Airspace Systems Program
 

A quarterly update of accomplishments and upcoming activities from NASA’s Airspace Systems Program. 

JULY—SEPTEMBER 2010
 

Technical/Programmatic Highlights
 

Dynamic Airspace Configuration: Articles 1, 2 Safe & Efficient Surface Operations: Articles 10, 11, 12, 13, 14
 

Interoperability Research: Articles 3, 4 Super Density Operations: Articles 15, 16, 17, 18, 19, 20, 21
 

Partnership Research: Articles 5, 6, 7, 8, 9 Traffic Flow Management: Articles 22, 23, 24
 

www.nasa.gov See inside for details 
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1 NASA and FAA Researchers 

Collaborate on Dynamically 

Managing Airspace, June 2010

Details: NASA researchers and FAA members 

of the Concept Development Group met with 

active airspace line managers from the FAA 

SPARC (Strategic Planning Advisory Review 

Cadre) team June 7-10 to discuss dynamic 

airspace configuration scenarios. SPARC team 

members provided feedback on acceptability, 

limitations, and coordination requirements 

for changing airspace boundaries in the FAA 

mid-term high altitude concept environment. 

They also provided positive and constructive 

feedback on the experiment plan for a NASA 

human-in-the-loop (HITL) simulation, 

planned for August 2010, exploring the role 

of the human operator in dynamic airspace 

configuration. Based on SPARC team feedback, 

the experiment plan for a fast-time mid-term 

DAC benefit analysis has been modified. 

They strongly recommended that airspace 

changes within mixed equipage airspace in 

the mid-term stay within controller areas of 

specialization. Dynamic airspace configuration 

within higher altitude generic airspace where all 

aircraft are trajectory-based operations (TBO) 

equipped should not be constrained to areas of 

specialization. The FAA concept development 

group will use the results of this modified fasttime analysis and the August HITL simulation 

to support their future research plan. 

2 Generic Airspace Human-In-TheLoop Simulation Completed, July 2010

Details: Phase 4 of the Generic Airspace 

research effort was completed with a successful 

human-in-the-loop simulation led by Dr. 

Richard Mogford and the Generic Airspace 

Team, comprised of software developers and 

researchers from SimLabs and the Human 

Systems Integration Division at Ames. The 

human-in-the-loop simulation, hosted in 

the Radar Air Traffic Control Laboratory in 

the Crew-Vehicle Systems Research Facility 

(CVSRF), evaluated methods for providing 

important airspace information and reducing 

sector information requirements to allow 

future air-traffic controllers to manage air 

traffic in NextGen airspace with reduced 

training. The simulation also investigated 

the effect of segregation based upon aircraft 

equipage based segregation on the FAA’s 

mid-term High Altitude Airspace Concept. 

The Controller Information Tool (CIT), 

an en-route auxiliary display developed and 

refined in previous phases of this research 

effort, was used to provide controllers with 

critical situational information. The Multi 

Aircraft Control System (MACS) software 

was used to realistically emulate the FAA’s 

en-route air traffic control user interface and 

was configured to provide several NextGen 

automation tools including digital data 

communication between pilot and controller 

(datacomm), conflict probe, and manual 

conflict resolution. Four controller positions, 

staffed by experienced operational air traffic 

controllers, were configured to run the same 

traffic scenario under four different conditions 

(baseline, weather impacted, increased traffic 

flow, datacomm). Various levels of datacomm 

capabilities were also evaluated in the scenario. 

Controller performance data, impressions, 

and opinions were collected to evaluate system 

effectiveness. The simulation was successfully 

conducted over a one week period in July 2010 

and the data are currently being analyzed. 

3 Simulation of Trajectory-Based 

Operations with Data Link 

Produces New Insights, June 2010

Details: NASA Ames researchers are exploring 

a near-term concept for Trajectory-Based 

Operations (TBO) with air/ground data link 

communication that promises to dramatically 

improve the efficiency of operations in enroute and transition airspace. In over 100 hours 

of laboratory simulation, NASA’s prototype 

ground automation system–comprised of 

several new algorithms integrated into the 

Center/TRACON Automation System 

(CTAS)–controlled full Fort Worth Center 

traffic during busy periods from 32 recent 

weekdays and involving over 37,000 individual 

flights. Prototype functionality included 

wind-favorable direct routes, minimum-fuel 

descent profiles, minimum-delay conflict 

resolutions, improved conflict detection for 

climbing flights, and independent tactical (0-3 

minutes) conflict detection and resolution. 

The simulation environment modeled datalink 

delay characteristics and trajectory prediction 

uncertainty (aircraft weight, wind, and pilot 

execution delay). Analysis of the resulting 

data has identified several new and important 

automation and concept requirements for 

TBO with datalink. Top-of-descent prediction 

errors are the most significant contributor to 

loss-of-separation events, and improvements 

to descent predictions are required to achieve 

reliable minimum-fuel descent profiles in 

medium to heavy traffic. Under metering 

conditions, where aircraft are merging and 

descending to a common fix, the pilot’s 

responsiveness in executing resolution 

maneuvers is especially critical; to reduce the 

variability, maneuver execution start points 

must be included as part of the trajectory 

clearance to the aircraft. Improvements to 

the climb detection logic have effectively 

enabled the automation to detect a majority of 

conflicts resulting from climb uncertainty, the 

second-largest cause of conflicts. Unlike today’s 

operational system, Conflict Alert, groundbased tactical conflict alerting automation must 

alert when an altitude amendment is entered, 

but before the aircraft starts the maneuver. 

In every other loss of separation case in this 

analysis, tactical automation (TSAFE, the 

tactical separation assisted flight environment) 

prevented any loss of separation. The proposed 

concept and automation reduced the number 

of flight plan amendments by a factor of eight. 

A paper documenting the complete results 

will be presented at the 2010 Congress of the 

International Council of the Aeronautical 

Sciences, and the system is now being prepared 

for human-in-the-loop simulation testing in 

September/October 2010. 

Technical/Programmatic Highlights 
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• Jul. 27-29: Generic Airspace Phase 4 HITL 

Experiment, NASA Ames

• Aug. 2-5: AIAA Guidance, Navigation and 

Control Conference

• Aug. 2-5: AIAA Modeling and Simulation 

Technologies Conference

• Aug. 10-19: Flexible Airspace II Experiment, 

NASA Ames 

• Sep. 8-9: Green Aviation Conference, 

NASA Ames

• Sep. 13-15: AIAA Aviation Technology, 

Integration and Operations Conference

• Sep. 19-24: International Council of 

Aeronautical Sciences (ICAS) 2010

• Sep. 22-23: Integrated Arrival and Departure 

Surface Research Transition Team Meeting, 

NASA Ames

• Sep.: Terminal Area Precision Scheduling 

Simulation (TAPSS) Completed

• Sep.: Collision Avoidance for Airport Traffic 

(CAAT) Fast-Time Simulation Study, 

NASA Langley

• Oct. 3-7: 29th Digital Avionics Systems 

Conference (DASC)

• Oct. 6-7: ASP Users Forum

• Oct. 11-22: Trajectory-based Operations 

with Datacom Simulation, NASA Ames

• Oct. 19-21: Partnership for AiR 

Transportation Noise and Emissions 

Reduction, Cambridge, MA

• Oct. 21: Friends and Partners in Aviation 

Weather Meeting, Atlanta, GA

• Oct. 24-27: Air Traffic Control Association 

(ATCA) Annual Conference, 

Washington, DC

• Oct. 26-28: JPDO/AFRL UAS Workshop, 

Dayton, OH 

• Oct. 27-28: NASA/ONERA Workshop, 

NASA Ames

• Oct.: Separation Assurance Dynamic 

Weather Batch Study, NASA Langley

4 Adaptive Climb Trajectory 

Prediction Feedback Algorithm 

Improves Conflict Detection 

Performance, August 2010

Details: Trajectory prediction for aircraft in 

climb is not as accurate as it is in the cruise or 

descent phases of flight, and the inaccuracy 

contributes to higher missed- and false-alert rates 

for conflict detection involving climbing aircraft. 

An algorithm to improve climb trajectory 

prediction accuracy by adapting trajectories 

based on observed radar track data has been 

developed and evaluated using a preliminary 

set of 18 actual Fort Worth Center departures. 

The algorithm utilizes rate-of-climb feedback 

to adjust the aircraft weight parameter used 

in trajectory predictions. Results indicate 

the adaptive algorithm reduces the standard 

deviation of altitude errors for a five-minute 

look-ahead time by a factor of four, from 2400 

feet to 600 feet. In addition, it also halved the 

standard deviation of top-of-climb time errors 

from two minutes to one minute. When applied 

to a climbing conflict scenario in a real-time 

simulation, the adaptive climb algorithm 

improved the conflict detection lead time from 

one minute to 5.5 minutes. Further evaluation 

with additional flights and simulated loss-ofseparation cases is planned.

5 User Preferences Research Presented 

at the JPDO Flight Prioritization 

Workshop, May 2010

Details: Dr. Kapil Sheth was an invited speaker 

at the Joint Planning and Development Office 

(JPDO) Flight Prioritization Workshop in 

Washington, DC during the week of April 26th. 

The three-day workshop was organized by Ms. 

Peggy Gervasi, JPDO Director of Strategic 

Interagency Initiatives, and was chartered to 

assess twelve concepts for prioritizing flights 

in the NextGen environment. The workshop 

participants included representatives from the 

airlines, general aviation, and the ATM research 

community. Dr. Sheth presented a concept 

he is researching that prioritizes flights based 

on credit points administered by the Federal 

Aviation Administration (FAA). The 10-member 

panel’s initial feedback was that the credit points 

concept was the most thoroughly researched 

concept to date. Final recommendations from 

the panel will be provided after the third 

workshop, to be held in July 2010. A panel 

member has contacted Dr. Sheth, and additional 

experiments to further this research are being 

explored directly with the FAA’s Technical 

Operations (FAA-ATO) organization. 

6 Airspace Concept Evaluation System 

(ACES) Results Workshop, June 2010

Details: The Systems Modeling and 

Optimization Branch hosted a three day 

workshop to share research utilizing the Airspace 

Concept Evaluation System (ACES). ACES is 

a non-real-time, computer simulation of local, 

regional and nationwide flight operations from 

gate departure to arrival. ACES’s overarching 

objective is to provide a flexible simulation 

and modeling environment that can assess the 

impact of future Air Traffic Management (ATM) 

tools and concepts. This workshop was attended 

by 47 researchers and software developers, which 

included representatives from the Joint Planning 

and Development Office (JPDO), the FAA 

Technical Center, NASA Ames Research Center, 

NASA Langley Research Center, Aerospace 

Computing Inc., Intelligent Automation Inc., 

Logistics Management Institute, Raytheon, 

Sensis, and the University Affiliated Research 

Center. Researchers presented completed or 

ongoing assessments of several ATM concepts. 

The concepts included integrated arrival and 

surface scheduling, separation assurance, 

terminal area merging and spacing, dynamic 

airspace configuration, and integration of 

traffic flow management and dynamic airspace 

configuration. Representatives from the 

JPDO were interested in using ACES as a 

system-wide cost and benefit analysis tool. Of 

particular interest were studies of the behavior 

and interactions of multiple ATM concepts 

in the presence of weather. The JPDO were 

also interested in using ACES in conjunction 

with other tools, such as tools for calculating 

noise and emissions. Representatives from 

the FAA Technical Center were using ACES 

to perform benefits assessments of planned 

upgrades scheduled for inclusion in their EnRoute Automation Modernization (ERAM). 

Overall, the workshop feedback was positive and 

attendees requested to have similar workshops 

in the future on an annual basis and possibly 

Research Events 

and Activities

Continued on page 4
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establishing an ACES user group.

7 NASA Ames Senior Scientist for Air 

Traffic Management Tours DLR 

Laboratories, July 2010

Details: Dr. Banavar Sridhar, the NASA Ames 

Senior Scientist for Air Traffic Management, 

completed a series of meetings and tours of 

several German Aerospace Center (Deutsches 

Zentrum fur Luft und Raumfahrt, or DLR) 

laboratories in Hamburg, Braunschweig, 

Cologne, and Oberpfaffenhafen, in July 2010. 

Dr. Sridhar met with DLR scientists and 

researchers and provided briefings of mutual 

interest on the topics of traffic flow management 

and optimization, as well as recent research 

efforts in modeling and developing operational 

strategies for dealing with persistent aircraft 

contrails. In turn, Dr. Sridhar was introduced to 

the various projects underway at DLR, including 

climate modeling and the impact of volcanic 

ash; arrival, departure and surface operations; 

conflict detection and resolution; engine 

technology; and airport operations. The Aviation 

Systems Division at Ames has had a number of 

extensive and productive collaborations with 

the DLR-Braunschweig laboratory over the 

past 20 years, and is currently hosting a visiting 

researcher, Mr. Joern Jakobi, who is an expert on 

airport surface operations. 

8 FAA Aviation Rulemaking 

Committee for ADS-B Applications 

to NextGen Air Traffic Management, 

 July 2010

Details: Mr. Brent Weathered was invited 

to be a member of the ADS-B IN Aviation 

Rulemaking Committee (ARC) and attended 

the kickoff meeting on the 1st of July. Automatic 

Dependent Surveillance-Broadcast (ADS-B) 

is a technology upon which NASA and FAA 

are currently basing efforts to modernize the 

Airspace System. Recently, the FAA issued a 

new Rule for ADS-B out (aircraft and ground 

targets sending info OUT to ground based Air 

Traffic Management facilities), and now FAA is 

planning to implement the IN portion (aircraft 

receiving IN information about other aircraft, 

messages, and possibly weather info). This 

implementation is crucial to realizing the vision 

of NextGen. 

The ADS-B IN Aviation Rulemaking 

Committee, which includes industry, user 

and ATC representatives, both domestic 

and international, is tasked with providing a 

roadmap and technical recommendations for 

implementation of ADS-B IN in the National 

Airspace System, bridging the gap between 

research and implementation. Implementation 

of this roadmap may result in rulemaking, thus 

the requirement for designation as an Aviation 

Rulemaking Committee. The ARC has a twoyear charter, with meetings expected monthly, 

to support FAA 2014 budget formulation. Full 

ADS-B implementation is planned for 2020. 

9 Research Presented at NASA 

Green Aviation Summit, 

September 2010

Details: On September 9th, Dr. Banavar 

Sridhar, Dr. Yoon Jung, and Mr. Richard 

Coppenbarger presented their research in a 

panel on Environmentally Friendly Airspace 

Operations at NASA’s Green Aviation Summit. 

Dr. Sridhar presented concepts and challenges 

for en route operations, including simulation 

and optimization techniques in the design of 

traffic flows to reduce the formation of contrails 

and the evaluation of tradeoffs between different 

types of aircraft emissions. Dr. Jung reported 

on his airport surface research to reduce the 

environmental impact of stop-and-go taxi 

operations. His team conducted a human-inthe-loop study whose initial results indicated 

that, with improved surface procedures and 

algorithms, the average number of stops made 

by each departure aircraft in the departure 

runway queue was reduced by more than half, 

consequently reducing departure taxi times. 

Mr. Coppenbarger presented a concept for fuel 

efficient, continuous descents, describing the 

simulations and flight testing that have been 

conducted to date to develop and refine the 

technology enabling such descents in busy traffic 

conditions. The Summit, held at NASA Ames on 

September 8 and 9, was attended by government, 

industry, and academic experts and was hosted 

by the Aeronautics Research Mission Directorate. 

The Summit webpage is http://www.aeronautics.

nasa.gov/calendar/20100908.htm. 

10 Human-in-the-Loop Airport 

Surface Scheduling Simulation 

Completed, April – May 2010

Details: The Spot and Runway Departure 

Advisory (SARDA) airport surface scheduling 

• Nov. 3-5: International Conference on 

Human Computer Interactions, Orlando, FL

• Dec.: En Route Descent Advisor /3D Path 

Arrival Management Experiment, 

NASA Ames 

2011

• Jan. 4-7: AIAA Aerospace Sciences Meeting, 

Orlando, FL 

• Mar. 29-31: ASP Technical Interchange 

Meeting, San Diego, CA

Research Events and 

Activities Continued

About This Newsletter

The Airspace Systems Program issues this 

quarterly newsletter to report on completed 

research activities and to provide a record of 

current and upcoming events of interest to the 

community. If you have questions about any of 

the information in this issue, please contact John 

Cavolowsky at NASA-ASP@nasa.gov.
5

simulation was successfully conducted April 

26 to May 7. SARDA is an airport scheduling 

system comprised of separate but integrated 

scheduling components. Two components of 

SARDA were investigated in this simulation, the 

Runway Scheduler, which provides the Local 

Controller with departure and active runway 

crossing sequence advisories and the Spot 

Release Planner, which provides the Ground 

Controller with times and sequences for releasing 

aircraft from the spot into the movement area. 

The two-week human-in-the-loop simulation 

explored a proof of concept where tower 

controllers metered ground departure traffic at a 

holding position short of the taxiway and at the 

queue feeding the departure runway. Data was 

collected on scheduling algorithm performance, 

concept feasibility, controller advisory usability, 

controller workload and situation awareness, and 

environmental impact (as measured by derived 

fuel consumption). Participants included two 

retired controllers, who controlled aircraft to 

the three east-side terminals of the Dallas-Fort 

Worth International Airport, and pseudo-pilots 

who maneuvered the simulated aircraft. The 

scheduling algorithms are expected to increase 

the efficiency of taxi operations by reducing 

the runway queue size and taxi delays, thus 

enabling fuel savings and reduction in engine 

emissions while maintaining maximum departure 

throughput. Data analysis is underway.

11 International Journal 

Publication on NextGen 

Research and Technology, 

 June 2010

Details: A paper entitled “Evaluation of MixedMode Data-Link Communications for NextGen 

4DT and Equivalent Visual Surface Operations” 

was published in the journal “Air Traffic Control 

Quarterly” (Vol. 18, Issue 2, pp. 177-212, June 

2010). The authors were Lawrence (Lance) J. 

Prinzel III, Kevin J. Shelton, Denise R. Jones, 

Angela S. Allamandola, Jarvis (Trey) J. Arthur 

III, and Randall E. Bailey of the Crew Systems 

and Aviation Operations Branch. The article 

discusses how the Next Generation Air Transportation System (NextGen) may create a radically 

different approach to air traffic management with 

dramatic shifts in the tasks, roles, and responsibilities for the flight deck by 2025. The paper 

describes human-in-the-loop simulation research 

examining the impact of one of the key enabling 

technologies for NextGen - data-link communications – on performance, safety, and flight crew 

awareness and workload during four-dimensional 

trajectory (4DT) operations and equivalent visual 

surface operations. Overall, the results indicate 

that retaining or replacing party-line information with a voice-by-exception data-link can have 

significant safety impacts for surface operations.

12 Successful Checkout of Integrated Departure Scheduling Software, June 2010

Details: NASA’s Precision Departure Release 

Capability (PDRC) team recently completed 

an evaluation of the initial PDRC software 

system. The software includes NASA’s Surface 

Management System (SMS) and the research 

version of the FAA’s Traffic Management Advisor 

(RTMA) enhancements that implement the 

initial PDRC functionality. The PDRC research 

activity will assess the value of using precise, 

surface trajectory-based OFF (take-off) time 

predictions for en-route departure scheduling 

in Call for Release situations. PDRC uses SMS 

to generate precise OFF time estimates and 

delivers these to RTMA for en-route departure 

scheduling. The software integration was 

completed in May at NASA’s North Texas (NTX) 

Research Station and successfully evaluated in a 

series of tests using both recorded and live radar 

data. This integration and checkout activity sets 

the stage for an engineering shadow evaluation 

scheduled to begin in July 2010. Objectives 

for the July PDRC evaluation include further 

verification of software system performance, 

refinement of the operational concept and 

procedures and baseline data collection. 

13 Surface Conflict Detection and 

Resolution with Emphasis on 

Trajectory-Based Operations 

Kickoff Meeting, July 2010

Details: The research performed under this 

ARRA funded NRA will help incorporate 

conflict detection and resolution (CD&R) 

principles for surface traffic into existing 

capabilities. The NRA is expected to develop 

performance models of surveillance systems, a 

rule-based framework for short-term conflict 

detection, a probabilistic trajectory-predictionbased framework for long-term conflict 

detection, a search-based short-term conflict 

resolution algorithm, and long-term conflict 

resolution procedures. The NRA will then 

implement CD&R into these algorithms, 

integrate, and test them with surface traffic 

simulations. The kickoff meeting was attended 

by NRA researchers from Optimal Synthesis 

Incorporated and Tufts University, including 

Dr. Victor Cheng (Principal Investigator) and 

Dr. Jason Rife (Co-Principal Investigator). Dr. 

Cheng presented the motivation, objectives, and 

work plan for his team’s NRA effort.

14 Conflict Detection and 

Resolution Study for Airport 

Surface Operations Underway, 

 August 2010

Details: On August 25, a kickoff meeting was 

held between Sensis Corporation and NASA 

researchers to discuss concepts, requirements, 

and algorithms for ground-based airport surface 

conflict detection and resolution (CD&R). 

This kickoff meeting marked the beginning 

of a rigorous study to provide a concept of 

operations for ground-based CD&R, CD&R 

algorithms and software, and performance 

metrics to assess CD&R function performance. 

This work is being funded by the American 

Recovery and Reinvestment Act (ARRA). The 

primary objective of the study is to provide air 

traffic controllers with robust CD&R strategies 

to mitigate potentially serious conflicts on airport 

surfaces by fusing new CD&R software modules 

to the FAA’s existing Surface Management 

System (SMS). These new modules will one 

day provide air traffic controllers with efficient 

strategies for dealing with taxiway, ramp area, and 

runway conflicts. In addition to efficiency gains, 

the CD&R function will enhance safety for all 

vehicles on the airport surface by incorporating 

a hierarchical system for prioritizing strategic, 

tactical, and critical surface conflicts. 

15 Energy Navigation (eNav) 

Experiments in the Air Traffic 

Operations Laboratory Validates 

Low Noise Guidance (LNG) Reduction in 

Noise and Fuel Burn, March – July 2010

Details: NASA Langley researchers conducted 

batch experiments in the Air Traffic Operations 

Laboratory (ATOL) that showed an approximate 

1 dB reduction in noise and 3% less fuel burned 

during descent and arrival using Low Noise 

Guidance (LNG). This work validated on a 

large scale (over 13,000 flights) the performance 

achieved by pilots during the Low Noise 

Learn more about the Airspace Systems Program at: www.aeronautics.nasa.gov/programs_asp.htm
6

Guidance (LNG) flight test. In addition, this 

work demonstrated the feasibility of using 

advanced FMS guidance in a highly dynamic 

terminal environment to maximize flight 

efficiencies. The objectives of the study were 

to minimize fuel burn, noise and emissions of 

aircraft during arrival and landing operations 

through the development and evaluation of 

a concept and associated technologies that 

combine dynamic energy-based trajectory 

generation with real-time flight guidance and 

energy-based auto throttle commands. An 

additional goal was to reduce the occurrence of 

missed approach situations. The approach used 

was to develop advanced Flight Management 

System (FMS) concepts and associated cockpit 

interfaces and then to conduct a sequence of 

experiments and studies to evaluate the concepts 

and interfaces, as well as develop crew procedures 

for optimized guidance. 

16 NASA Meets with Southwest 

Airlines to Discuss NextGen 

Technologies, May 2010

Details: Researchers from NASA Ames Research 

Center visited Southwest Airlines to discuss 

Southwest’s recent experience with using 

NextGen avionics systems. These systems, 

called Area Navigation (RNAV) and Required 

Navigational Performance (RNP), allow aircraft 

to fly any desired flight path within the coverage 

of specific navigation aids and monitor their 

navigation performance. This technology is 

critical in support of concepts for NASA’s Super 

Density Operations (SDO) research. Southwest 

Airlines is an early adopter of this technology and 

NASA researchers gained Southwest’s feedback 

on NASA’s Super Density Operations concept 

of operations using RNAV and RNP. NASA 

researchers Harry Swenson, Paul Borchers and 

Keenan Roach met with Southwest’s RNAV/

RNP project leaders including their Chief 

Technical Pilot and FAA representatives from the 

Southwest Region. NASA presented information 

on the North Texas Research Station (NTX) 

and current research in Terminal Area Precision 

Scheduling Research. Southwest representatives 

were very interested in NASA’s research since 

they felt that they would not be able to take full 

advantage of their RNAV/RNP investment until 

our research is implemented. SWA expressed 

interest in a follow-up visit with NASA to 

review their operations using the RNAV/RNP 

technologies which would be very beneficial to 

NASA’s SDO research.

17 NASA Meets with FAA to 

Discuss Improving Terminal 

Area In-Trail Conflict Detection 

Technologies, June 2010

Details: On June 22nd, Federal Aviation 

Administration (FAA) representatives Mike 

Prichard, Suzanne Newman and six other exTerminal Controller/Traffic Managers responsible 

for the FAA’s development of the Automated 

Terminal Proximity Alert (ATPA) tool met 

with Aviation Systems Division researchers and 

managers to discuss progress and plans in an 

ongoing collaboration towards improving the 

ATPA tool. ATPA monitors in-trail separation 

on the final approach course. Early next year, 

the FAA expects to complete another phase of 

software improvements to ATPA. NASA has 

been working with the FAA to understand the 

effect of aircraft landing speeds on monitoring 

in-trail separation. The purpose of this meeting 

was for the FAA to share their current ATPA 

plans and for NASA to provide results of their 

relevant research. Aviation Systems Division 

researchers have been investigating the prediction 

of aircraft spacing compression during final 

approach using a variety of methods, and have 

also been developing a terminal area aircraft 

conflict detection algorithm and concept of 

operations. Both NASA and the FAA agreed to 

continue these meetings and expressed support 

for continued collaboration. The FAA agreed 

to provide more operational data to NASA 

researchers to improve the terminal area aircraft 

conflict detection algorithm.

18 Terminal Area Precision 

Scheduling Completes 

Major Simulation Milestone, 

 July 2010

Details: The Terminal Area Precision Scheduling 

System (TAPSS) research team completed the 

third in a complex series of human-in-the-loop 

simulations of a new precision scheduling system, 

advanced navigation concepts and controller 

advisory tools for metering in the terminal radar 

approach control (TRACON) airspace. This 

system is a major technological enhancement 

to the NASA-developed and FAA-deployed 

Traffic Management Advisor (TMA) technology, 

providing precision metering schedules at flow 

merge-points within the terminal airspace. The 

TMA enhancements align with the FAA Time 

Based Flow Management long-term concept. 

A goal of the human-in-the-loop simulation 

was to evaluate the precision metering concept’s 

capability to conduct environmentally-friendly 

airspace procedures in high-density airspace. 

The experiment simulated traffic bound for 

Los Angeles International Airport, including 

Southern California TRACON and Los 

Angeles Air Route Traffic Control Center 

(Center) operations. Twelve pseudo pilots and 

eight air traffic controllers (operating three 

Center metering sectors, three TRACON 

feeder positions and two TRACON final 

positions) performed the simulation July 26-

30 at the air traffic management simulation 

laboratory at NASA Ames. This was the first 

Center-TRACON integrated simulation 

attempted in TAPSS, after having successfully 

completed separate TRACON and Center 

TAPSS simulations. The success of this Center/

TRACON integration simulation paves the way 

for four more weeks of evaluations scheduled 

in August and September to evaluate delay 

reduction and increased controllability of traffic 

along precision navigation routes in the presence 

of uncertainty. 

19 Completion of Terminal Area 

Paired Procedures Research, 

August 2010

Details: The Terminal Area Paired Procedures 

Research (TAPPR) team completed their third 

and final experiment using the Advanced 

Concepts Flight Simulator (ACFS) in the CrewVehicle Systems Research Facility (CVSRF). 

This series of experiments investigated pairing 

aircraft for precision approach and landing to 

closely-spaced parallel runways 750 feet apart in 

poor visibility conditions. The third experiment 

differed from the first two as it evaluated the 

operational roles and responsibilities between 

ground controllers and aircrew when using 

advanced flightdeck and ground automation. The 

Aviation Safety Program’s Intelligent Integrated 

Flightdeck Design and NextGen’s Super Density 

Operations research areas collaborated to develop 

this experiment and will share the test results to 

fulfill independent milestones. The experiment 

relied on a concept developed by Raytheon and 

flight deck automation developed by Langley. 

The experiment offered different levels of 

automation to the pilots, and provided different 

types of informational displays that allowed 

the pilots to monitor the conformance of their 
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aircraft to inter-pair spacing requirements. Test 

scenarios began about 100 miles from the airport, 

where aircraft from different arrival streams were 

logically paired and brought to a coupling point 

15 miles from the runway threshold with one 

aircraft 5 to 25 seconds in trail of the other. The 

experiment ran for three weeks with experienced 

air-traffic controllers and commercial airline 

crews serving as experimental participants. 

20 Visits to Two New York Air 

Traffic Control Facilities 

and Meeting with the Port 

Authority of New York/New Jersey (PANY/NJ) 

in Support of Runway Management Research, 

August 2010

Details: During August 26-27, 2010, Gary Lohr 

(LaRC Crew Systems and Aviation Operations 

Branch) met with representatives of the Port 

Authority of New York/New Jersey (PANY/NJ) 

and two air traffic facilities serving the New York 

area in support of Airspace Systems Program’s 

runway management research. Several weeks ago, 

the PANY/NJ invited members of the System 

Oriented Runway Management Team (SORM) 

to observe the operation of a departure metering 

program that is in place at John F. Kennedy 

International Airport (JFK). The metering 

program uses a system designed and operated by 

Passur Aerospace, Inc., under contract to the Port 

Authority and is designed to reduce queue length 

at the departure runway by assigning taxi times 

based on a real-time estimate of when the aircraft 

will be ready to taxi. The goal is to maintain a 

queue of 6-8 aircraft per 15-minute period on 

each departure runway. The system was originally 

developed in 1993 for use during periods when 

there were delays due to snow, and eventually 

for use when the Severe Weather Avoidance 

Program (SWAP) was activated. Although 

several other airports have similar systems, 

only the system at JFK is used on a daily basis 

regardless of weather conditions for the peak 

departure periods. Visits were also conducted to 

both the New York Terminal Radar Approach 

Control (TRACON) and the JFK Airport Traffic 

Control Tower (ATCT). JFK is the operational 

environment selected for the validation of 

SORM capabilities; as such, operational 

procedures for both of these facilities are of 

significant interest. At the TRACON, discussions 

were held addressing traffic flow management 

(TFM) for JFK and surrounding airports. TFM 

is envisioned to be a key factor in future runway 

management. At the ATCT, discussions with 

tower staff personnel focused on the issue of 

surface congestion and the effects of the Port 

Authority’s departure metering system on surface 

operations. Information obtained through each 

of these visits will be used to further the research 

team’s understanding of air traffic operations. 

In the case of the departure metering program, 

NASA will share information concerning the 

direction and results of runway management 

research as this may influence how their program 

functions. An additional benefit of these visits 

is the continued development of relationships 

with experts in the respective domains. The NY 

area service providers have been very cooperative 

and are considered an extension of the runway 

management research team. 

21 NASA Administrator Bolden 

Tours Aviation System Lab, 

September 2010

Details: NASA Administrator Charles Bolden 

visited Ames Research Center to attend the 

Green Aviation Summit. In addition to 

giving the keynote address at the Summit, 

Mr. Bolden, accompanied by Aeronautics 

Associate Administrator Dr. Jaiwon Shin, was 

given a demonstration and briefing of the 

NextGen research in trajectory-based operations 

and terminal area precision scheduling by 

researchers Dave McNally, Eric Mueller, and 

Harry Swenson.

22 Longest Convective Weather 

Forecast Yet Shows Promise for 

Use in Air Traffic Management, 

 June 2010

Details: Data from the Consolidated Storm 

Prediction for Aviation (CoSPA) was analyzed 

to determine its potential use in predicting the 

impact of convective weather on airspace capacity. 

CoSPA is the result of a collaborative effort 

across government agencies, universities, and 

private organizations to generate a tool capable of 

predicting the location and intensity of convective 

weather up to eight hours in advance. Three days 

of CoSPA data were analyzed to estimate the 

impact of weather on airspace sectors, primarily 

measured by the percentage of a sector’s volume 

that was filled by convective weather. To assess 

accuracy, the predictions were compared against 

the observed weather. Initial findings show that 

the correlation of predicted to observed impact 

on sectors decreases as the look-ahead time is 

increased up to eight hours. A simple probabilistic 

model was also developed to show the likelihood 

of weather affecting a sector based on CoSPA 

predictions. The results suggest that CoSPA can 

be an effective tool to aid air traffic managers. 

23 Development of Predicted 

Contrail Frequency Index, 

July-August 2010

Details: Contrails are visible trails of water vapor 

produced by the exhaust of aircraft engines. 

Contrails appear and persist if aircraft are flying 

in certain atmospheric conditions, and their 

persistence results in reduced incoming solar 

radiation and outgoing thermal radiation in a 

way that accumulates heat on the Earth’s surface. 

In order to measure this effect, the predicted 

contrail frequency index was developed. The 

index predicts regions that would form persistent 

contrails and quantifies the severity. It is 

computed using weather forecasts and predicted 

aircraft locations. The results show that predicted 

indices in the immediate one to three hours are 

highly correlated with actual indices and have a 

high success rate in identifying regions with high 

contrail activities. Air traffic managers can use the 

predicted index in strategic planning to reduce 

contrail formations. The results of this study were 

presented for peer review feedback at the AIAA 

Guidance, Navigation and Control Conference 

in Toronto, Canada from August 2-5. 

24 Optimization Software Cleared 

for Open Source Release, 

September 2010

Details: Dantzig-Wolfe Decomposition is an 

optimization technique that can be used to solve 

certain problems in parallel. Software developed 

within the Systems Modeling and Optimization 

branch using this technique has been used to 

perform large-scale Traffic Flow Management 

optimization and is currently being integrated 

with the Advanced Concepts Evaluation System 

(ACES) tool. This software has been approved 

for open source release and will represent the 

only implementation of the algorithm available 

in any form commercial or otherwise.