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UAS in the NAS Project Recommends Well-Clear Distance
March 21, 2019

The Unmanned Aircraft Systems (UAS) Integration into the National Airspace System (NAS) project continues to support the national initiative of safely and seamlessly incorporating UAS with traditionally piloted air traffic, through NASA’s ongoing participation in the RTCA Special Committee 228 (SC-228). On March 7, 2019, the SC-228 Detect and Avoid (DAA) Working Group selected the safety distance (a.k.a DAA well-clear, or DWC definition) that a UAS with lower size, weight, and power (SWaP) is required to maintain, against traditionally piloted aircraft that are without a functioning transponder. This standard definition of well-clear sets the stage for the technological development of new airborne radar, electro-optical, and infrared sensors to detect aircraft.

The DAA Modeling and Simulation Team in the Aviation Systems Division led the efforts informing the selection of this DWC definition through a series of fast-time simulations and a human-in-the-loop experiment. The team also included colleagues from Ames Research Center’s Human Systems Integration Division, the DAA team at Langley Research Center, and industry partners MIT Lincoln Laboratory and Cal Analytics. The NASA team proposed four candidate DWC definitions based on considerations of safety and attenable sensor detection requirements. These candidates were subsequently evaluated by simulating millions of encounters that allow computation of safety and operational suitability metrics. Pilot performance and acceptability were also evaluated. Results helped the committee select a DAA well clear definition that was not only deemed safe, but also would lead to sensor performance requirements that industry thought it could achieve.

This work is fundamental to the proliferation of UAS in our national air transportation system and has received praise from the Federal Aviation Administration (FAA) and DAA system manufacturers. Next steps for the team are to perform an additional verification fast-time simulation, and assess the DAA well clear in a flight test (Flight Test 6), scheduled for later in 2019.

(POC: Gilbert Wu)

National NATCA ATD-2 Lead Transition and Visit at Charlotte Airport
March 21, 2019

John Short looks as Mike Smith points to something on a display in the American Airlines ramp tower.
AAL Ramp Tower: John Short (NATCA) and Mike Smith (AAL)

NASA Airspace Technology Demonstration 2 (ATD-2) team members provided a demonstration of the ATD-2 system in use at Charlotte Douglas International Airport (CLT, Charlotte, NC) March 11-12, 2019 to the new National Air Traffic Controller Association (NATCA) ATD-2 Lead, Mr. John Short. Mr. Short, a traffic management coordinator (TMC) from the Dallas-Fort Worth facility, observed surface metering and overhead stream insertion facilitated with the ATD-2 system from the CLT Tower/TRACON and American Airlines Hub Control Center (ramp tower). NASA briefed Mr. Short on the latest ATD-2 status and addressed questions about the project. Mr. Pete Slattery, the former National NATCA lead, also served as the CLT local representative for ATD-2. The CLT role is now assumed by Mr. Mike Hoprich, Charlotte TMC. NASA looks forward to working with the new NATCA ATD-2 Leads and is ever grateful for Mr. Slattery’s many significant contributions as National ATD-2 NATCA lead prior to this transition. (POC: Isaac Robeson, Bob Staudenmeier)

John Smith looks at something Pete Slattery is pointing to on a display in the Charlotte air traffic control tower.
Charlotte Air Traffic Control Tower: Pete Slattery, John Short

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Last Updated: March 29, 2019

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