Around 03:13 UTC on 21 June (22:13 local time) a flight of US Air Force KC-135 Stratotanker aerial refueling aircraft departed Altus Air Force Base in Oklahoma. Operating in two flights of four aircraft, the Stratotankers headed northeast toward Missouri. Those aircraft quickly climbed to the top of Flightradar24’s most tracked flights list—not because thousands of people find aerial refueling aircraft over the central US fascinating, but for the inference of their purpose.
Following dramatically increased intercontinental activity by US Air Force tanker and transport aircraft that began on 15 June, speculation grew that B-2 Spirit stealth bombers could be deployed to possibly attack Iran.
When the tankers over Missouri turned west and fanned out just south of Whiteman Air Force Base, home to the B-2 fleet, the number of users following the flights grew and the lead tanker became the most tracked flight in the world.

As the tankers from Altus returned to the base, those following along on Flightradar24 spotted a second set of tankers launching from Travis Air Force Base in California.
All a diversion
While flight following eyes were on the tankers heading west, there were seven B-2s and dozens of tankers flying east.

The first notice via ADS-B of the eastbound flight did not come until the aircraft turned back west. A group of at least six KC-135s were spotted west of Chania in the Mediterranean Sea around 03:35 UTC on 22 June.

Approximately six hours later a group of 10 tankers, including a mix of KC-135s and KC-46s was spotted northeast of the Azores. The tanker aircraft had been positioned to Lajes Field over the past week.

At no point were the B-2s visible on Flightradar24, they did not broadcast ADS-B or Mode S, the signals our network is capable of receiving. We’re often asked why military aircraft show up via ADS-B. It’s because they want to.