The airplanes in question are military tanker aircrafts, fueling the rumors that the US is planning an attack on Iran.
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The airplanes in question are military tanker aircrafts, fueling the rumors that the US is planning an attack on Iran.
What is happening?

Over 30 U.S. military aircraft have been relocated from American bases to Europe in just three days, according to flight tracking data reviewed by BBC Verify.
The planes are said to be military tanker aircrafts, used for refueling fighter jets and bombers mid-air.
Strategic Stops Across Europe

At least seven of these tanker planes, all KC-135 Stratotankers, were spotted making stopovers at U.S. airbases in Spain, Scotland, and England.
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The aircrafts were en route to unknown destinations, but were moved amid rising tensions between Israel and Iran.
Unusual Movements

Speaking with the BBC, Military analyst Justin Bronk from the Royal United Services Institute described the tanker deployments as “highly unusual,” suggesting the U.S. may be preparing for potential large-scale combat operations.
Israel-Iran Conflict as a Backdrop

While it’s unclear if the U.S. flights are directly connected, the timing has raised eyebrows among defence experts.
Monday, when the US President, Donald Trump, left the G7 Summit early, he told reporters that “we’re going to do something”, when asked about the situation in the Middle East.
Tankers Spotted Near Sicily and Crete

The KC-135s were later tracked flying east of Sicily, with six aircraft listing no destination.
One jet did land on the Greek island of Crete, adding to the uncertainty about their operational purpose.
“Strategic Ambiguity” in Play?

Vice-Admiral Mark Mellett, former head of the Irish Defence Forces, suggested to the BBC that the U.S. may be employing a strategy of deliberate ambiguity to pressure Iran diplomatically during ongoing nuclear negotiations.
Aircraft carrier Moves Closer to Middle East

The U.S. Navy’s aircraft carrier USS Nimitz is also on the move. Initially in the South China Sea, it was redirected towards the Middle East, cancelling a Vietnam stop due to an “emergent operational requirement.”
Fighter Jets and Bombers Ready for Action

The U.S. has also deployed F-16, F-22, and F-35 fighter jets to the Middle East.
The tanker planes now stationed in Europe can support these aircraft by extending their range through mid-air refueling.
Bunker Busters and B-2 Bombers

BBC Verify also reports that if the U.S. targets Iran’s underground enrichment facilities it would likely use GBU-57A/B bunker busters, which are so large only B-2 stealth bombers can carry them.
Bombers on the move

In late March, B-2 bombers were seen on Diego Garcia, a remote U.S. / UK military base.
Recent satellite images show no sign of the bombers, though, but as the island is withing B-2 striking distance of Iran, the bombers could soon return to the base.