ADS-B Shenanigans?

Thank you for printing in Augusts magazine the short letter I wrote, highlighting an issue I encountered just south of the Albany, N.Y., Class C airspace-a Cub showing an ADS-B altitude of 500 feet below sea level. (By the way, I passed the same Cub today at very close range. This time he wasnt showing up at all on ADS-B). In your response, you asked readers to report other anomalies, so heres one from a week or so ago.

Editorial Staff

Tuesday, October 01, 2019 at 12:00 AM ET

Verified

Key Takeaways:

A pilot reported multiple ADS-B anomalies in the same location, including an aircraft showing 500 feet below sea level altitude and another reporting over 1000 knots groundspeed, suggesting a potential issue with the ground station's data interpretation.
An app developer created a series of free, open-source apps (POH Performance) that calculate adjusted takeoff and landing distances for sloped runways, based on aviation research and considering various safety criteria.

See a mistake? Contact us.

Thank you for printing in August’s magazine the short letter I wrote, highlighting an issue I encountered just south of the Albany, N.Y., Class C airspace—a Cub showing an ADS-B altitude of 500 feet below sea level. (By the way, I passed the same Cub today at very close range. This time he wasn’t showing up at all on ADS-B). In your response, you asked readers to report other anomalies, so here’s one from a week or so ago.

I was in nearly the exact same location as I was for the prior report when my ADS-B In/Out transceiver, a Garmin GTX 345, highlighted an aircraft passing low overhead at a speed of 1033 knots. I eagerly acquired it visually, assuming it was a UFO. (There has been a spike in UFO sightings recently—I was hoping to report the first one with ADS-B compliance!)