Dear Evil Engineer,

I own a flying circus – by which I mean not a barnstorming troop but, quite literally, a circus that flies. My clowns, acrobats and circus animals wear kerosene jetpacks throughout the performance, ensuring an excellent view for all members of the audience. However, I’ve found that the loud noise of their customised jetpacks tends to alarm my dancing bears, elephants and poodles, preventing them from performing to the standard I expect.

I’ve come up with an idea for an alternative mode of flight: gigantic helium balloons, which I could additionally monetise as advertising space. So, how much helium will I need to lift a dancing elephant? And is this helium shortage I keep hearing of going to cause a problem – is there enough helium for my dozen elephants to continue performing?

Yours,

A showbiz villain

Dear villain,

I cannot pretend to know much about managing circuses, but this sounds like a fine proposal to me. Anyone who would...