One Step Closer to Smoother Skies
By: Federal Aviation Administration
Tags: Meteorology, Weather, Aviation, General Aviation, Airlines

By Callie Dosberg, FAA Office of Communications

Most of us would describe 2020 as a turbulent year. And while there’s not much to be done about that bumpiness, FAA researchers are now closer to helping pilots and controllers avoid turbulence in the sky using Automatic Dependent Surveillance-Broadcast (ADS-B) data.

“This research shows promise to bring an additional level of safety to the flying public and flight crews, like flight attendants who are actually injured by turbulence more often than passengers,” said Tammy Flowe, an FAA Research Meteorologist.

The research originated from an FAA employee’s submission to an FAA-wide challenge for innovative ideas to solve agency data challenges. He proposed using ADS-B data directly from aircraft to understand when it is experiencing turbulence. That information could then be shared with air traffic controllers, pilots and airlines to better assist in forecasting and planning to avoid turbulence. With approximately 133,000 U.S. aircraft already providing ADS-B reports, there is no need for airlines and pilots to buy additional equipment, and repurposing ADS-B data that already exists removes the subjective, and often intermittent, nature of pilot turbulence reports.

“In the first phase of research we wanted to determine if we could use the aircraft vehicles themselves as a sensing platform of turbulence in the atmosphere,” said Larry Cornman from the National Center for Atmospheric Research (NCAR), who is conducting the research on behalf of the FAA. In other words, does ADS-B report sudden shifts in aircraft movement that could be used to track turbulence? “The answer is yes, the information from the aircraft is going to be usable. Now in this second phase, we took a deeper dive to look at algorithmic concepts we can take from feasibility and move to operations.”

The lower panel shows the vertical rate data (black), the quantization level crossings (green), and color contours of the density of these crossings. The upper panel shows the vertical wind-derived turbulence values. Image: FAA

During this phase, a significant breakthrough occurred in the ability to identify and separate turbulence signals from non-turbulence ones in the ADS-B data, and researchers developed a method to identify and filter out normal aircraft maneuvers that might be mistaken or incorrectly flagged as turbulence encounters. In addition. While FAA and NCAR teams are encouraged by the research efforts so far, there is more to explore. Additional research will focus on scaling factors to account for how different aircraft experience turbulence.

“The whole point of this is to provide valuable information on turbulence for other vehicles that might be going through the airspace in the near future,” said Cornman. “For example, a small business jet and a 777 would respond to atmospheric turbulence differently, so we want a measure of the atmosphere itself that removes the aircraft dependency.”

Future efforts also include plans for an operational demo on a commercial aircraft in the coming year.

The blue and green curves in this chart show turbulence values from the vertical rate data, with and without the weighting, respectively. Image: FAA

“We hope to get something in front of users with a limited operational demo and we would like industry partners to help with that flight testing,” said Gary Pokodner, the Manager of the FAA’s Weather Technology in the Cockpit Program. “We’d like to put this to use on some airplanes where you could actually get live data reports and compare those with pilot assessments and other measures to see how it’s measuring turbulence.”

While more isn’t always better, when it comes to input data, additional data sources can help create more accurate meteorological and forecasting models. The FAA team believes this research could be impactful for the meteorological community in addition to aviation users.

“There’s not really a gold standard with turbulence measurement, and there are a lot of different technologies and new things hitting industry that they’re trying to figure out,” said Flowe. “We’re not there just yet with this research and we still have more to do, but this shows a lot of potential and gives a large amount of data that we just don’t currently have. And the more input data you have, the better the weather forecast models are. These extra data points can be important in the decision-making process for the airlines and pilots.”