Just before this BBC podcast gets underway, here's something you may not know.

My name's Linda Davies and I Commission Podcasts for BBC Sounds.

As you'd expect, at the BBC we make podcasts of the very highest quality featuring the most knowledgeable

experts and genuinely engaging voices. What you may not know is that the BBC

makes podcasts about all kinds of things like pop stars,

poltergeist, cricket, and conspiracy theories and that's just a few examples.

If you'd like to discover something a little bit unexpected,

find your next podcast over at BBC Sounds.

There'll be blue birds over the white cliffs of Dover

Hello and welcome to more or less on the BBC World Service.

We're the program that takes the numbness out of numbers and releases stats from Stasis and I'm Tim Harford.

The Battle of Britain took place 78 years ago in British airspace between the 10th of July and 31st of October 1940.

On the British side flew nearly 3,000 men, including nearly 600 from allies such as Poland, New Zealand, Canada and Czechoslovakia.

The southeast coast is still a daily witness of the German attempts to crush the Royal

airport, but the fight for the mastery of the skies is still very much on.

This week we'll be delving into the past, with an email from loyal listener Andrew.

It's often mentioned that the average lifespan of Spitfire pilots was four weeks.

Those pilots were heroes of course, but I've never quite understood how that figure for life expectancy was calculated.

Can you explain, Is it correct?

In the first year of this war, British pilots have brought down 1,752 in raids on this country.

These are the men who do it.

There were heavy losses on both sides, but was the life expectancy of pilots in the iconic spitfire really just four weeks?

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