Average Alert Times Supported by ATAR Classes A1, A2, and A3
This presentation shows the average warning and corrective alert times supported by the ATAR classes A1, A2, and A3
Unmanned Aviation Systems↗
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Low Size, Weight, and Power (SWaP) ATAR Analysis Results for Appendix C/D Updates
This presentation gives an update of the low SWaP sensor field of regard analysis results.
Wu, Gilbert↗
Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project: Low SWaP HITL 2, SC-228 Outbrief, EO/IR & ATAR Breakout
This presentation provides an overview of a recently completed human-in-the-loop simulation, conducted as part of the Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project. This study explored the differential effects of four low size, weight, and power radar declaration ranges on pilot and system performance. Pilots were to avoid DAA well clear against cooperative and non-cooperative aircraft under 1.5, 2, 2.5, and 3 nautical mile non-cooperative detection ranges. Results revealed that pilot performance was primarily influenced by warning-level alert duration, with sufficient alerting time being most prevalent at 2.5 nautical miles and above.
Monk, Kevin J.↗
Evaluation of D-1 tape and cassette characteristics: Moisture content of Sony and Ampex D-1 tapes when delivered
Commercial D-1 cassette tapes and their associated recorders were designed to operate in broadcast studios and record in accordance with the International Radio Consultative Committee (CCIR) 607 digital video standards. The D-1 recorder resulted in the Society of Motion Picture and Television Engineers (SMPTE) standards 224 to 228 and is the first digital video recorder to be standardized for the broadcast industry. The D-1 cassette and associated media are currently marketed for broadcast use. The recorder was redesigned for data applications and is in the early stages of being evaluated. The digital data formats used are specified in MIL-STD-2179 and the American National Standards Institute (ANSI) X3.175-190 standard. In early 1990, the National Media Laboratory (NML) was asked to study the effects of time, temperature, and relative humidity on commercial D-1 cassettes. The environmental range to be studied was the one selected for the Advanced Tactical Air Reconnaissance System (ATARS) program. Several discussions between NML personnel, ATARS representatives, recorder contractors, and other interested parties were held to decide upon the experimental plan to be implemented. Review meetings were held periodically during the course of the experiment. The experiments were designed to determine the dimensional stability of the media and cassette since this is one of the major limiting factors of helical recorders when the media or recorders are subjected to non-broadcasting environments. Measurements were also made to characterize each sample of cassettes to give preliminary information on which purchase specifications could be developed. The actual tests performed on the cassettes and media before and after aging fall into the general categories listed.
Ashton, Gary↗
Sulfur volcanoes on Io?
The unusual rheological properties of sulfur are discussed in order to determine the distinctive volcanic flow morphologies which indicate the presence of sulfur volcanoes on the Saturnian satellite Io. An analysis of high resolution Voyager imagery reveals three features which are considered to be possible sulfur volcanoes: Atar Patera, Daedalus Patera, and Kibero Patera. All three features are distinguished by circular-to-oval central masses surrounded by irregular widespread flows. The central zones of the features are interpreted to be domes formed of high temperature sulfur. To confirm the interpretations of the satellite data, molten sulfur was extruded in the laboratory at a temperature of 210 C on a flat surface sloping 0.5 deg to the left. At this temperature, the sulfur formed a viscous domelike mass over the event. As parts of the mass cooled to 170 C the viscosity decreased to a runny stage, forming breakout flows. It is concluded that a case can be made for sulfur volcanoes on Io sufficient to warrant further study, and it is recommended that the upcoming Galileo mission examine these phenomena.
Greeley, R.↗
Sulfur Volcanoes on Io?
The unusual rheological properties of molten sulfur, in which viscosity decreases approximately four orders of magnitude as it cools from 170 to 120 C, may result in distinctive volcanic flow morphologies that allow sulfur flows and volcanoes to be identified on Io. Search of high resolution Voyager images reveals three features--Atar Patera, Daedalus Patera, and Kibero Patera--considered to be possible sulfur volcanoes based on their morphology. All three average 250 km in diameter and are distinguished by circular-to-oval central masses surrounded by irregular, widespread flows. Geometric relations indicate that the flows were emplaced after the central zone and appear to have emanated from their margins. The central zones are interpreted to be domes representing the high temperature stage of sulfur formed initially upon eruption. Rapid quenching formed a crust which preserved this phase of the emplacement. Upon cooling to 170 C, the sulfur reached a low viscosity runny stage and was released as the thin, widespread flows.
Greeley, R.↗
Unmanned Aerial Systems (UAS) Integration into the National Airspace System (NAS)
NASA's Unmanned Aerial Systems (UAS) integration into the National Air Space (NAS) project has been working closely with the FAA and RTCA Special Committee 228 to identify and break down barriers to UAS integration. A focus of this work is on detect and avoid (DAA) technologies. A pilot has responsibility to see and avoid other aircraft and to remain "well clear," using their best judgment (Federal Aviation Regulations (FAR) Sec. 91.113). For UAS to perform this function, the see function is replaced by sensors to detect the other aircraft. Secondly, the pilot judgment of well clear has to be replaced by a mathematical expression. For Phase 1 of this effort, a well clear violation was defined if all three of these conditions are true: a) the horizontal clearance is less than 4000 ft., and b) the vertical clearance is less than 450 ft., and c) the time to loss of well clear is less than 35 seconds. This definition was developed with a great deal of community input and testing to ensure interoperability with Air Traffic Control (ATC) and pilots of manned aircraft. Appropriate guidance, alerting and displays were developed to allow UAS, with the appropriate sensors, to effectively maintain well clear. This work contributed to FAA Technical Standard Orders: TSO-C211, Detect and Avoid and TSO-C212, ATAR for Traffic Surveillance. Phase 2 of this work extends the operational environment to include the terminal area and lesser capable aircraft that might not have the payload capability to carry the RADAR defined in Phase 1. This session reports on work from Phase 1 and initial work in Phase 2.
UAS↗
Detect and Avoid: Efforts from NASA's UAS Integration into the NAS Project
NASA's Unmanned Aerial Systems (UAS) integration into the National Air Space (NAS) project has been working closely with the FAA and RTCA Special Committee 228 to identify and break down barriers to UAS integration. A focus of this work is on detect and avoid (DAA) technologies. A pilot has responsibility to see and avoid other aircraft and to remain "well clear," using their best judgment (Federal Aviation Regulations (FAR) Sec. 91.113). For UAS to perform this function, the see function is replaced by sensors to detect the other aircraft. Secondly, the pilot judgment of well clear has to be replaced by a mathematical expression. For Phase 1 of this effort, a well clear violation was defined if all three of these conditions are true: a) the horizontal clearance is less than 4000 ft., and b) the vertical clearance is less than 450 ft., and c) the time to loss of well clear is less than 35 seconds. This definition was developed with a great deal of community input and testing to ensure interoperability with Air Traffic Control (ATC) and pilots of manned aircraft. Appropriate guidance, alerting and displays were developed to allow UAS, with the appropriate sensors, to effectively maintain well clear. This work contributed to FAA Technical Standard Orders: TSO-C211, Detect and Avoid and TSO-C212, ATAR for Traffic Surveillance. Phase 2 of this work extends the operational environment to include the terminal area and lesser capable aircraft that might not have the payload capability to carry the RADAR defined in Phase 1. This session reports on work from Phase 1 and initial work in Phase 2.
Detect and Avoid (DAA)↗