Darryl Wilson, a Democratic Unionist Party (DUP) councillor, told BBC News NI people got in touch to tell him of “unusually loud and prolonged aircraft noise in the skies” on Tuesday night.
“People wanted to understand what they were hearing and why there appeared to be increased activity so late at night,” he added.
“Given the wider international context, it’s understandable that people are curious about what’s happening and why.”
Researchers looking at online flight-tracking websites found a potential answer to the noise – possible activity in the area by two US Air Force Stratotanker aircraft.
These huge planes are used to refuel other aircraft in mid-air.
Aviation expert David Learmount said the noise probably was caused by these planes, either while they were actively refueling, which he said takes about 10 minutes, or while one was flying in “lazy circles” waiting for the other.
“Modern airplanes constantly bleep out information about who they are, what height they are, their identification,” he told BBC News NI.
“So, the flight-tracking websites are pretty reliable, they are reading pretty much the same info as air traffic control.”
