Aviation journalist and former RAF pilot David Learmount said it was the “first time in years” he had heard of a pylon falling off.

He said Typhoon jets used pylons to mount things including missiles or extra fuel tanks to the outside of the aircraft.

“It is just literally a structure on to which additional equipment can be bolted for a particular mission,” he said.

“It’s quite a heavy piece of equipment and I’m glad there wasn’t a person or animal underneath it because they wouldn’t have survived if it had hit them.”

In his opinion, he said the most likely cause of the failure was some sort of error when the pylons were being mounted.

“Either that, and I think this is slightly less likely, a failure in one of the attachment parts,” he added.

Mr Learmount said there was a lot of military activity in the skies over Lincolnshire and Yorkshire.

However, he said, due to the rural landscape of the region, any objects falling from planes were likely to land in “open country”.