Residents across Tayside were woken up by low-flying helicopters on Monday night.
Residents in Dundee, Inchture, Milnathort and Arbroath all reported hearing helicopters shortly after midnight.
One man, who lives in the north of Dundee said: “I woke up around 12.15am after hearing what I thought was a low-flying helicopter above the house.
Chinook helicopters flying low over Tayside
“I thought it might be a police or coastguard helicopter but I looked online and couldn’t see anything on Flightradar.
“I had a fan on in my room so I thought, for a moment, that must have accounted for the noise but it definitely sounded like a helicopter.
“It was really noisy – it must have been going pretty low and fast.”
The Royal Air Force (RAF) has confirmed the noise was created by Chinook helicopters on a training mission.
It comes as Chinooks from RAF Odiham operate from RAF Lossiemouth in Moray for a fortnight.
An RAF Spokesperson said: “Chinook aircraft from 27Sqn at RAF Odiham are deployed on exercise based out of RAF Lossiemouth in Scotland.
“During the exercise crews are training with various military units around the east and west coast of Scotland.
“The Chinook aircrew must maintain their proficiency to low-fly in night tactical formation, using night vision devices.
“These low-flying skills are essential to practise before they are used in an operational environment.
“The crews take every precaution to avoid causing a nuisance to local residents, particularly those not used to routine Chinook helicopter operations.”
It comes weeks after an RAF aircraft was spotted flying low above parts of Dundee as part of a training flight.
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