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Forecasting Smoother Rides for Passengers, Crew

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A forecasting tool called Graphical Turbulence Guidance (GTG) helps commercial and general aviation pilots make better flight-planning decisions.

GTG creates 4-D atmospheric turbulence forecasts for the 48 contiguous United States as well as much of Canada and Mexico.

In-flight turbulence is the leading cause of injuries to passengers and crew in non-fatal aircraft accidents.

Anyone who has flown enough has felt the chop, bumps, and rough patches of the skies known as turbulence, which can create unpleasant rides and even cause serious injuries.

In-flight turbulence is the leading cause of injuries to airline passengers and flight attendants in non-fatal accidents. Between 2010 and 2015, 213 serious turbulence-related injuries were reported to the National Transportation Safety Board.

To lower the risk of encountering in-flight turbulence, NextGen's Aviation Weather Division partnered with the National Center for Atmospheric Research to develop Graphical Turbulence Guidance (GTG). The fully automated, web-based turbulence forecasting tool helps commercial and general aviation pilots make more informed flight-planning decisions that can enhance cabin safety and potentially ease controller workload.

"GTG provides better turbulence information for added safety, efficiency, and capacity," said Tammy Farrar, an FAA NextGen research meteorologist. "It can help keep pilots at an optimal altitude and keep flights on an optimal flight route."

pilot holding a display showing GTG

With the GTG web-based advisory tool, pilots can access turbulence forecasts for the 48 contiguous United States as well as much of Canada and Mexico.

Farrar and Deborah Smith, a computer specialist and NextGen Weather safety lead, supported the development of GTG's newest release, including the coordination of safety risk management activities required for its deployment.

Pilots who access the tool can get a 4-D atmospheric turbulence forecast for the 48 contiguous United States as well as much of Canada and Mexico. Forecasting in locations outside of these areas is under development.

The tool has several features:

  • Flight crews can more effectively plan smoother, safer routes around mountainous regions by using the mountain wave turbulence forecasting.
  • Users can obtain specific turbulence intensity levels according to aircraft type and weight class.
  • Forecasts are available up to 18 hours in advance.
  • An extended forecasting range includes lower altitudes to help general aviation pilots.

Delta Air Lines was the nation's first air carrier to test GTG with a flight crew in normal operational environments, with the goal of enhancing crews' ability to anticipate and react to turbulent conditions.

The airline participated in the safety analysis supporting the newest version and later developed a computer tablet application — Flight Weather Viewer — to better leverage the GTG platform. Flight Weather Viewer depicts current and forecasted turbulence along Delta flight paths and can be accessed in the cockpit using the aircraft's Wi-Fi network. The application relies on data generated by automated aircraft reports, pilot reports (PIREP), radar, and satellite-based sensors to produce hourly forecasts.

Since Flight Weather Viewer's inception, Delta has reported a significant reduction in flight crew radio calls to controllers requesting PIREPs about turbulence and fewer altitude changes based on available PIREP data.

The FAA continues to expand its partnership with industry to research and develop innovative tools like GTG to ensure that aircraft operators and the flying public can experience the safest and most comfortable airspace system possible.

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