NextGen Surface Observation Capability


Assessing the FAA's Sensor Network for Its Readiness To Support The NextGen Initial Operating Capability

Schematic view of the requirement, forecast and observing relationships that define the limits of potentially achievable forecast results at FOC.  Additional roles of sensor capabilities in support of validation, assimilation and basic studies are also shown.

Optimization of relevant weather observation and forecasting capabilities are essential for conducting safe and efficient flight operations in the NAS.  It is imperative, therefore, to ensure that the FAA's current and future weather observing and forecasting capabilities are adequate to satisfy NextGen requirements.  Under the Reduce Weather Impact (RWI) program, the FAA has set up a multi-institutional team for conducting an assessment of relevant weather sensors on the ground, and on airborne and space platforms.  This sensor assessment is also known as “Right Sizing” effort.  Collaborators in this research include the National Center for Atmospheric Research (NCAR), the Massachusetts Institute of Technology (MIT) Lincoln Laboratory, the University of Oklahoma (OU), and Indiana University (IU).

Estimated probability of detection (POD) of a small, but intense, simulated microburst for the LLWAS network installed at Denver International Airport (DEN).

The assessment of requirements, the construction of sensor evaluation tools, the survey of available sensor systems/technologies, and the synthesis of essential scientific and NAS operational constraints governing strategies to meet future needs represent complex factors which must be well understood before they can be brought together in a meaningful analysis of sensor system gaps.  NCAR’s recent work has sought a methodology to identify and assess gaps in today’s terminal ground sensor systems to support planning for sensor network evolution.  The goal of that evolution is to meet observing system needs for SDO airspace at the NextGen 2025 FOC. 

A high-level assessment of SDO functional and performance requirements was done, which identified a vast array of requirements to be poorly represented or not credible.  Missing is also a more efficient system of up-to-date tables that would outline “observe”, “forecast” and other objects and link those objects to desired sets of attributes, such as spatial/temporal resolution, forecast frequency, latency, and others as appropriate.  There appears to be no forecast quantity (e.g., wind speed, in-flight icing, turbulence, visibility) that can meet the stated requirements today and likely won’t meet these requirements for FOC. 

A detailed assessment of the primary (FAA or NWS owned) and supplementary (other available Federal, state or cooperative) sensor network for each of the major US airports was conducted.  The analyses considered the correlation characteristics of meteorological fields in space and time as a critical factor that must be understood for effective network design. 

Since 2011, the "Right Sizing" effort is narrowing on the development of a Flexible Terminal Sensor Network (FTSN). NCAR has been supporting the FAA in this effort with a focus specifically on the integration of the Low Level Windshear Alert System capability into the FTSN. A FTSN demonstration experiment is planned for late 2012 that will showcase potential improvements that can be achieved toward meeting NextGen requirements.


Please direct questions/comments about this page to:

Scott Landolt

Assoc Scientist IV