On a cloudy afternoon in the summer of 1959, Lieutenant-Colonel William Rankin climbed into the cockpit of his jet fighter for what should have been a routine navigational flight from Massachusetts to North Carolina. That’s what it should have been. Unfortunately for Rankin, his engine conked out when he was flying directly above a monstrous cumulonimbus, more commonly known as a storm cloud. These behemoths of the troposphere are estimated to contain as much energy as ten Hiroshima-sized bombs. The largest of them, measured from top to bottom, can be considerably taller than Mount Everest. On his dashboard, the decorated Korean War veteran was horrified to see the bright red ‘fire’ light flashing urgently. When he pulled the lever for the back-up power supply, it came away in his hand. He was at an altitude of approximately 47,000 feet. The temperature outside was -50ºC. Rankin had no choice, however, but to yank the ejection seat handle behind his head, explode out of the cockpit, and begin his plummet into the waiting cumulonimbus.

Clouds needn’t be boring. Certainly, when gazed up at from miles below by the prostrate idler sucking on a blade of grass, they can seem fluffy and harmless, even soporific, but in the words of Constable, who believed the sky to be ‘the chief organ of sentiment’ in his landscape