It's there for a very interesting reason

You might be driving to Heathrow Aiport, ready to set off on holiday, then spot something strange.

Sitting on the tarmac is a huge green aeroplane, seemingly without windows - and it looks very old and possibly ever a little charred.

That makes sense - it's been there for years and has never moved from that spot.

But why?

One intrigued passerby took to reddit's 'what is this thing' thread to see if they could get answers about this strange vehicle, and they got a lot of responses.

It turns out this hunk of metal is used for training Aircraft Rescue Firefighters - the people who save you from a burning aeroplane and put out the flames should the worst happen.

One commenter said: "I did a fire training in something similar at the airport. It was a plane that the insides must have been thrown around, and various compartments added.

"We had to go in, in full gear, in pitch black, and do a left hand search along the walls with a buddy to retrieve 50kg sand bags. Was intense.

Firefighters participating in a simulated rescue training session

"They also had another one nearby that had jet fuel sprayed out and lit on fire near various parts of the plane, and we learnt various techniques for putting out fires.

"There was a few really other cool obstacles aswell."

While the plane isn't a replica of an actual passenger jet - it's a lot smaller and has fireproof material - it's made to simulate the important bits of dealing with a plane on fire, specifically the door heights and interiors.

It's a mashup of several types of aircraft so crews can practise solving the different challenges each one poses.

Source