The bang was shocking in its intensity. Deafening and mind-numbing. I thought at first all the cars in London had hit each other at speed. Windows shattered, people covered their ears instinctively and the reverberations actually shook the pavement under our feet. I was with the two beautiful twins, Selina and Katrina, and they both turned to me wide-eyed, their hands still protecting their ears.

I shrugged to show I too did not know what on earth had happened. Then I looked up, and saw what was making all the noise. A gigantic airship had just broken the sound barrier at an extremely low altitude. As it passed over Bond Street, where Selena, Katrina and I were at the time, it looked for all the world like the opening scene in Star Wars, with a massive starship rumbling ominously overhead. Even at its extremely high speed the vehicle was so large that it took several seconds to pass over us. It had few distinguishing features.

As the noise level diminished, Selena shouted, “What was that?” I am a scientist, and I did not like to admit to total ignorance about something I had had just seen with my own eyes.

“Well, whatever it is, it has just passed from below Mach speed to well above it.” This comment didn't just impress the twins. Several shocked members of the public were clearly reassured that here was someone who had some idea about what had just happened. Others though had been so deafened by the experience they missed my words of wisdom.

A chirping sound followed close on the dying rumbles, and I knew exactly what that was. A message from the BBC News Department on my mobile, to make my way to a studio at once, to comment on what had just occurred. My scientific credentials, and my willingness to comment, made me their first choice. Accompanied by the twins, I made my way to the nearest studio, the other side of Oxford Street.

In the foyer the doorman recognised me, naturally, and asked, “What was it, Gustave? What on earth was it?”

I smiled reassuringly at him, and said, “Watch the broadcast, and find out.”

The two girls came into the studio with me, and I was hastily prepared for my few seconds on camera. I had done this sort of thing before, so I considered what I could and should say while make-up did their thing on me. Back in the studio I was shown to my seat, the producer gave a brief count down, and we were on.

The newsreader on duty faced the camera, and in a suitably grave voice, said, “Here is a news flash. Just fifteen minutes ago, the whole of the south coast, including London, suffered the effects of an extremely large, low-flying object. An estimated 20,000 windows have been shattered in London alone. At least 6,000 people have been completely deafened by the noise.

“We have in the studio Professor Gustave Bates, who has kindly consented to explain the phenomenon to us. Professor?”

I looked confidently into the camera. “Fortunately I experienced the passage of this low-flying object at first hand. I can confidently explain it, I am sure. However, my explanation may be somewhat unbelievable. I would ask you to suspend your disbelief for a while. It is my considered judgement that what so many of us have just seen was the Queen Elizabeth II.” I paused, for effect, and for this to sink in.
“I say this because I saw the twin screws of that great ship as it passed overhead. They were blurred by their excessively high speed, but I recognised them. Very few people have been told that the motive power of the ship is supplemented by a nuclear engine. I am convinced that for reasons as yet unknown, the nuclear engine has gone critical. Super-heated steam has stressed the turbines to make the ship surf its way towards the English Channel, and take off somewhere south of Devon. By the time it flew over London it had definitely reached Mach One, and the noise of something so big, at that speed, was very loud indeed. Weight for age, it is now definitely the fastest thing built by man.”

I became more serious. “If this broadcast is reaching anyone aboard the flying ship, they must contact the captain or any of the crew, and insist that they wait until they are over California until they pull on the emergency handbrake. My calculations give them a good chance of a safe splashdown in the Atlantic. They need to stop those screws spinning as they pass over Los Angeles or close by.”

I pressed the familiar button on my desk to indicate to the newsreader that I had finished. He took over smoothly. “It is a relief to know what has happened, and we all wish the passengers and crew the best of luck when, and if, they splashdown, as Professor Gustave puts it. We will now return you to normal programming, and will come back on air as soon as more information is available.”

With the tissues provided, I wiped off the make-up, and went over to Selina and Katrina. “How did I go?”

“Disgusting!” Selina said to my surprise, getting to her feet.

“Awful!” agreed Katrina. “We didn't follow you exactly, but we heard you say 'twin screws', and neither of us expected you to mention that on national television. We are leaving, and we never want to see you again.”

The reaction on board the Queen Elizabeth II was far more satisfactory. They took my advice, and one passenger, a Mrs Davenport, relayed my instructions to the captain. In a most spectacular way, the ship landed safely, causing tidal waves for hundreds of miles in all directions. No-one was killed, thank goodness, but a few were slightly bruised. There were no plans to make this a regular feature of every cruise. I chose to bring them down into the Atlantic to provide the minimum disruption to their trip, and they reached Southampton safely, a little behind schedule.

I had to cope with the familiar crowd of reporters as I took my very shaggy dog for a walk that evening.

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