Mysterious blue glow traced to Flying Banana

Is it a UFO? Is it the Northern Lights? No, it's the "Flying Banana".

A blue glow that has lit up Lincolnshire's night sky in recent weeks has been traced to an unlikely source: a bright yellow train.

Network Rail said the mysterious light comes from its new measurement train – nicknamed the Flying Banana – which looks for faults on the line for engineers to repair.

The company said on hazy nights, equipment from the yellow train can create a blue glow "that looks like something from the X-Files" as it tests overhead lines.

"But it's not flying saucers," a spokesperson said. "Just our Flying Banana helping to keep trains running reliably."

The bright blue glow has been spotted across the county, including from stations such as Metheringham.

Network Rail said the Flying Banana, which covers 115,000 miles (185,075 km) of track, is "vital to keeping the railway safe and reliable".

The train, which travels at speeds up to 125mph (201 km/h), records track conditions and identifies faults before they can pose a risk.

To do this, it uses specialist equipment, such as a track‑geometry system, laser track scanners and a high‑resolution video camera.

According to Network Rail, by monitoring the tracks in this way, it avoids blocking railway lines and saves the company millions of pounds.

The nickname appears to be a playful take on the famous Flying Scotsman.

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