It is 75 years since the Battle of Britain - so in September, 75 cyclists will ride from Paris to London in aid of the RAF Benevolent Fund.

I’m doing it – 211 miles in four days on a Brompton folding bike (except for the Channel – we do that bit by ferry).

But for a little light exercise, over the few weeks before we go I’m climbing a bike to Battle of Britain combat altitude at Biggin Hill, one of the frontline fighter stations in 1940. Simple – climb hill, go back down, climb again, repeat until I’ve climbed 12,000ft.

Hence Operation Grand Old Duke of York.

Why support the RAFBF? When we ask people to go to war on our behalf, some pay a high price: lost lives, lost limbs, lost sanity. So we owe them two things return.

First, we'd better have a pretty serious reason for asking them. In 1940 we had.

Second, we should look after survivors who need help and the families of those who don't come back.The RAFBF helps.

The ride's target is to raise £75,000. Great - except that last year the Fund spent £18.7 million.

Every little helps. Kindly join the queue for that "Donate" button up there on the right.