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ForeFlight Crowdsources AHRS-based Turbulence Reports
By: Matt Thurber
Caption: The reported turbulence layer shows not only three turbulence levels but smooth air as well
Word Count: 697
ForeFlight has released a turbulence-reporting feature that sources information from its Sentry and Sentry+ ADS-B In receivers. The reported turbulence feature captures internal attitude sensor data from the Sentry units when pilots’ iPads are connected to the internet, either in the air if connectivity is available or after landing.
Unlike subjective pilot reports of turbulence, which rely on pilots’ varying perceptions of intensity, the data from the Sentry devices is objective and derived from the units’ sensitive attitude sensors. Traditional turbulence information is based on pilot reports, which are generally biased towards giving more turbulence reports versus fewer smooth air reports, as well as forecast models and winds aloft forecasts, all of which pilots use to try to predict and avoid turbulence while planning flights, according to ForeFlight.
The turbulence reports are generated from the Sentry data and show varying levels of intensity from smooth to severe at altitudes flown by aircraft carrying the Sentry devices. The reports are generated worldwide, and ForeFlight has already captured turbulence data from all seven continents.
To access the new turbulence information, ForeFlight users select the reported turbulence layer in the map mode and then adjust the desired altitude using the slider. Smooth air is depicted as a gray dot on the map, while turbulence is shown in three colors: light (yellow), moderate (orange), and severe (dark orange). Tapping on any of the dots brings up the "reporting flight’s altitude, airspeed, and aircraft type as well as the age of the turbulence report, up to about six hours,” according to ForeFlight. The reported turbulence layer is displayed on both the map and profile views.
Reported turbulence information, when delivered via an aircraft’s airborne connectivity system, isn’t real-time as some processing has to take place. “It’s near-real-time,” said Cole Crawford, senior product manager at ForeFlight Labs. “The shortest time I’ve seen is six minutes. If you have an active connection, it’s [usually] 10 to 15 minutes turn time because we’re trying to optimize the use of the network.”
Tens of thousands of Sentry units have been delivered, and pilots flying all sorts of aircraft use them. Typically, there are about 1,200 turbulence pilot reports in the U.S. per day, but the Sentry-generated turbulence information is already “orders of magnitude more,” he said.
The reported turbulence feature doesn’t depend on Sentry access to ADS-B ground stations, just the capture of sensor data and sharing it with ForeFlight. The Sentry+ has a passthrough feature so that it can connect to an aircraft’s Wi-Fi router and to the internet when connectivity is available—and to an iPad at the same time.
There are two levels of reported turbulence service available: low and all. The low service (up to 14,000 feet) is included with ForeFlight Pro Plus and Performance Plus subscription plans when users register their Sentry/Sentry+ on their ForeFlight account. Once registered, ForeFlight is offering a 50 percent discount on the all layer (normally $100). A Sentry is not required to view the reported turbulence layer, nor is Sentry registration. Individual ForeFlight users can purchase the low layer for $50 or all for $100 without registering (or having) a Sentry. Business and enterprise users should contact ForeFlight's sales department for pricing information.
“No one enjoys flying through turbulence, whether you’re piloting a single-engine piston or riding in the back of a jet,” said Henrik Hansen, ForeFlight’s chief technology officer. “That’s why we’re thrilled to provide this groundbreaking new tool for planning around turbulence using actual inflight turbulence data, a capability most pilots have never had access to before. This innovation is a testament to our cutting-edge engineering and robust product design, as well as the transformative potential of portable ADS-B when widely adopted. We’re excited to see how this feature enhances flight planning and flying for all ForeFlight users.”
The recent ForeFlight update that includes reported turbulence also brings back the popular U.S. lowest-tilt radar with new lower latency and improved spatial resolution and a landing factor selector and TOLD card for the runway analysis service.