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Abbott, Terence

Publications and source records attributed to Abbott, Terence.

Development of an Interval Management Algorithm Using Ground Speed Feedback for Delayed Traffic

One of the goals of NextGen is to enable frequent use of Optimized Profile Descents (OPD) for aircraft, even during periods of peak traffic demand. NASA is currently testing three new technologies that enable air traffic controllers to use speed adjustments to space aircraft during arrival and approach operations. This will allow an aircraft to remain close to their OPD. During the integration of these technologies, it was discovered that, due to a lack of accurate trajectory information for the leading aircraft, Interval Management aircraft were exhibiting poor behavior. NASA's Interval Management algorithm was modified to address the impact of inaccurate trajectory information and a series of studies were performed to assess the impact of this modification. These studies show that the modification provided some improvement when the Interval Management system lacked accurate trajectory information for the leading aircraft.

Barmore, Bryan E.

Considerations in the Integration of Small Aircraft Transportation System Higher Volume Operations (SATSHVO) in the National Airspace System (NAS)

The Small Aircraft Transportation System Higher Volume Operations (SATS HVO) concept holds the promise for increased efficiency and throughput at many of the nations under-used airports. This concept allows for concurrent operations at uncontrolled airports that under today s procedures are restricted to one arrival or one departure operation at a time, when current-day IFR separation standards are applied. To allow for concurrent operations, SATS HVO proposes several fundamental changes to today's system. These changes include: creation of dedicated airspace, development of new procedures and communications (phraseologies), and assignment of roles and responsibilities for pilots and controllers, among others. These changes would affect operations on the airborne side (pilot) as well as the groundside (controller and air traffic flow process). The focus of this paper is to discuss some of the issues and potential problems that have been considered in the development of the SATS HVO concept, in particular from the ground side perspective. Reasonable solutions to the issues raised here have been proposed by the SATS HVO team, and are discussed in this paper.

Lohr, Gary W.

Airborne-Managed Spacing in Multiple Arrival Streams

A significant bottleneck in the current air traffic system occurs at the runway. Expanding airports and adding new runways will help solve this problem; however, this comes at a significant cost, financially, politically and environmentally. A complementary solution is to safely increase the capacity of current runways. This can be achieved by precise spacing at the runway threshold with a resulting reduction in the spacing buffer required under today s operations. At the NASA Langley Research Center, the Advanced Air Transportation Technologies (AATT) Project is investigating airborne technologies and procedures that will assist the pilot in achieving precise spacing behind another aircraft. This new spacing clearance instructs the pilot to follow speed cues from a new on-board guidance system called Airborne Merging and Spacing for Terminal Arrivals (AMSTAR). AMSTAR receives Automatic Dependent Surveillance-Broadcast (ADS-B) reports from the leading aircraft and calculates the appropriate speed for the ownership to fly in order to achieve the desired spacing interval, time or distance-based, at the runway threshold. Since the goal is overall system capacity, the speed guidance algorithm is designed to provide system benefit over individual efficiency. This paper discusses the concept of operations and design of AMSTAR to support airborne precision spacing. Results from the previous stage of development, focused only on in-trail spacing, are discussed along with the evolution of the concept to include merging of converging streams of traffic. This paper also examines how this operation might support future wake vortex-based separation and other advances in terminal area operations. Finally, the research plan for the merging capabilities, to be performed during the summer and fall of 2004 is presented.

Barmore, Bryan

Subjective, physiological, and performance measures of eight primary flight displays

A simulator study to determine the effect on pilot performance of electronically represented altitude and airspeed information on the primary flight display using moving tape formats is presented. The study used a seemingly random, unpredictable guidance task and focused on three areas relating to the representation of information on moving tape formats: tape centering, trend information, and tape orientation. Results suggest that moving tape displays with actual values centered is better than tapes with reference values centered and that high-to-low airspeed tape orientation is better than low-to-high orientation. With trend information absent, subjects devoted 50 percent more attention to the secondary task relative to display configurations with trend presented.

Abbott, Terence