The Convective Weather Product Development Team (PDT), a core team of scientists and engineers from NCAR, NSSL, and MIT Lincoln Laboratory, was formed in 1996 as part of the reorganization of the FAA Aviation Weather Research Program. The PDT was tasked to develop a convective weather forecast algorithm that would produce operationally useful forecast products and to deliver these products to users, since convective forecasts are needed to meet air traffic airspace planning and safety needs.
Before major algorithm development began, PDT members visited terminal (tower and TRACON) and enroute ATC supervisors, TRACON and enroute traffic management coordinators (TMCs), and airline dispatchers in order to understand the forecast products that were currently available to them and to solicit feedback on their needs for a near future product. The users interviewed all had access to the products from an MIT Lincoln Laboratory prototype Integrated Terminal Weather System (ITWS)1. In order to reach the pilot community, a pilot survey about existing pre-flight and enroute convective weather information and how to improve it was created and distributed at the OshKosh Fly-In in August of 1997.
The feedback from the users was that currently their only forecast information was available through the ITWS Storm Extrapolated Position (SEP) product that shows the storm (VIP level 3 and above) leading edge location at 10 and 20 minutes in the future. The 10 and 20 minute forecasts were heavily used by the controllers while the traffic planning users, the TMCs and the airline dispatchers needed longer lead time forecasts.
The users answered questions that focused on the features of various types of convection (line storms, air mass storms) that were most important to their decision making and also on forecast accuracy, spatial extent, intensity and lead time. Also, they were shown (and their feedback requested) various display concepts for the Terminal Convective Weather Forecast Product.
The consensus results were that improved line storm predictions were more important than air mass storm predictions since pilots could deviate around cells except when they were directly over the airport, whereas the width, extent, orientation, and density of line storms often made them impenetrable. With regard to forecast accuracy and lead time, users' answers depended upon their function. Terminal users needed a 30 minute forecast out to 50nm with 90% accuracy; the TMCs wanted a 60 minute forecast out to 200 nm with 70% accuracy; and the airline dispatchers ideally wanted a forecast of 2 hours plus the length of each flight so that they could hold planes on the ground rather than reroute in the event of convective weather. Although ideally they wanted a long lead time, dispatchers were willing to accept less accuracy than the other positions: 30-50% was deemed acceptable.
This paper presents the detailed results of the user interviews as well as the results of the pilot surveys.
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1The FAA has contracted with Raytheon to develop the operational version of the ITWS, which will be deployed starting in 2002.
* This work was sponsored by the Federal Aviation Administration. The views expressed are those of the authors and do not reflect the official policy or position of the U.S. Government.
+ Opinions, interpretations, conclusions and recommendations
are those of the authors and are not necessarily endorsed by the United
States Air Force
The 8th Conference on Aviation, Range, and Aerospace Meteorology