Dozens of people took to Twitter and Facebook after being woken by what sounded like a low-flying aircraft circling the Island at about 3 am – well after the Airport had closed.
Commenting on Facebook, Fabio Moura wrote: ‘It went on for some time – I did look out the window and could only see what seemed to be a glow but not that bright.’
Islander Daniel Straiton added: ‘I heard it in town for sure – thought it was strange for a plane to be landing/taking off at that time.’
However, the most likely culprit is believed to be a boat – as the atmospheric conditions were ideal for bouncing the sound of an engine back down to ground level.
However, the only boat around Jersey’s coast in the early hours did not leave the Harbour until about 45 minutes after the noise was heard – and so if a vessel was to blame it was likely to have been in French waters.
John Searson, principal meteorologist at Jersey Met, said an ‘inversion’ in the atmosphere would have allowed the noise to be heard – even from a vessel out of Jersey’s immediate area.
‘We have looked at the met conditions and we believe the noise being heard was from a boat rather than a plane.
‘There was very warm air aloft with colder air below 1,000 ft. The boundary between the cooler air and the warmer air is likely to have reflected the sound back to earth. Conditions were right for sound to travel a long way.’
Meanwhile, Ports of Jersey say the noise may have come from a Swearingen Merlin plane en route from Birmingham to Porto which was passing at 18,000 ft.
A spokesman said: ‘Jersey’s Air Traffic Control has reviewed its radar recordings and advised that around the time that this noise was heard there was a flight overhead Jersey heading in a north to south direction flying at an altitude of 18,000 ft.
‘The aircraft in question is a fairly slow turbo prop and at that height and with the wind direction it was likely that this is the sound that residents heard as we have no record of any other aircraft in Jersey airspace at this time.’
PREVIOUS NOISE MYSTERIES
- In February 2012 dozens of people were woken by a plane noise. It turned out that the noise was caused by a 32-year-old Russian cargo plane travelling at 32,000 ft. The cold and still conditions apparently made the aircraft sound much closer than it was.
- In 2013 residents on the Waterfront reported hearing a strange alarm-like noise. The sound which went on for a week was found to be coming from a faulty extractor at KFC.
- In 2009 residents in an area of St Ouen dubbed The Millais Triangle were driven to distraction by a low-frequency humming noise. During the same year, they suddenly discovered that their car key fobs had stopped working. Neither mystery has ever been solved.
