We’re back in the race. Or rather, war.

Tonic watch emerges on deck on Thursday evening to find three other yachts within range. Barclays and SAIC are clearly visible on the horizon ahead, while Save the Children is abreast of us, a couple of miles off our port beam. Through binoculars we can see signs of activity on our rival’s deck. What are they up to? It feels like spying on an enemy ship and trying to work out which cannons they are bringing into play.

Save the Kids’ big gun is their spinnaker. We watch a successful hoist, but the huge sail doesn’t appear to give them any advantage. We’re relieved. After our scary experiences last night, we’re reluctant to raise our own kite. Excuses are ready to hand. Is that fog coming in? Look how hard they’re finding it to control the sail. Is that a broach? Look, they’re all over the place.

Eventually, however, we have to admit the obvious. The wind has gone further aft and Save the Children is clearly pulling ahead of us. Still we delay. Then comes the inevitable decision: we have to raise our own spinnaker.

The hoist is successful, but it took us far too long and, by the time Tonic goes off watch at midnight, we’ve lost valuable ground.

At 0400 we’re back on deck. A few hours later, though, the wind begins to veer. We’re being forced off our rhumb line. The spinnaker has to come down.

By Friday lunchtime, though, Besso has made good the previous night’s losses. We have the even bigger kite aloft and we’ve overhauled Save the Children and left them trailing in our wake. Now, however, we’re not making much headway. The wind speed has dropped and we’re dawdling along at three or four knots.

This would be unsatisfactory at the best of times; today, though, there are special circumstances. The VHF radio crackles into life. A Nimrod reconnaissance plane is contacting the Challenge fleet. “Are you aware, sir, that you are holding up a live firing exercise?” Our course, it transpires, has taken us into a naval firing range.

We may be in a race, but when the Royal Navy is playing war games, you have to let them win.