This happened last weekend.
GPS And ADS-B Problems Cause Cancelled Flights
Something strange has been going on in the friendly skies over the last day or so. Flights are being canceled. Aircraft are grounded. Passengers are understandably upset. The core of the issue is GPS and ADS-B systems. The ADS-B system depends on GPS data to function properly, but over this weekend a problem with the quality of the GPS data has disrupted normal ADS-B features on some planes, leading to the cancellations.
Here is an update: Not a GPS Signal Problem – Corrupted Receiver Update
According to a notice from NBAA Traffic Services sent yesterday, “Numerous calls and emails have come in to the desk this morning in reference to GPS signal disruption.” The disruption appears to affect only certain Collins Aerospace (formerly Rockwell Collins) GPS receivers, and Collins Aerospace confirmed to AIN , “We identified a technical issue with our recently released GPS product(s) impacting availability, and have since determined the root cause and the resolution. We are engaging with our customers to ensure continued safe operational capability.”