Seeing a pair of AC72s fly around San Francisco Bay was a first for me, but Wednesday’s test programme was also a first for the Americas Cup Defenders Oracle – this was their first day of two boat testing. With Jimmy Spithill aboard boat number two, the latest boat and Ben Ainslie helming boat number one, rebuilt and reconfigured after the capsize back in October, the pair conducted a series of upwind and downwind trials on the Cup race course area. But their day afloat also provided a spectacular display as to what we are about to receive as the 34th America’s Cup gets under way.

With the Louis Vuitton Challengers series due to kick off in just over a week, I had been invited out to San Francisco to see how the final preparations were taking shape. Part of that was a close up view of the AC72s in the flesh and in action. So riding aboard a high speed, surface piercing catamaran we scorched our way out into San Francisco Bay to take a look at Oracle Racing’s first day of two boat testing.

Even before these boats lift up onto their hydrofoils they are impressive machines. Aside from the striking sight of these two jet black, wing masted cats with their sizzling, razor straight white wakes streaming aft across a billiard table flat sea, the first thing to strike me as we approached was how the engine note from our twin turbo jets never changed as we lined up astern to follow the pair. We had sat pretty at 18-20 knots on our trip around from the base and having located the boats our driver gently took up formation with these cats with no change in speed on our part. This is not normal, particularly in just 10-11 knots of breeze. Yet as the odd white cap popped up across the Bay confirming the gentle nature of the building thermal breeze, both boats were slicing along at double the wind speed.

When it comes to manoeuvring they are equally impressive. A tack takes about 13 seconds from full speed to full speed, yet unlike the flogging and clatter of the former monohull lead mines, these boats slip through the breeze almost silently, accelerating out of the tack like a fighter jet from an aircraft carrier’s deck.

But the real fun started when they headed downwind.

Ainslie’s crew had hoisted a small gennaker but Spithill did not and bore away under jib and wing alone to line up against his team mate. As the pair sliced along, Spithill was the first to rise onto his foils keeping pace and heading with Ainslie who was yet to lift out of the water. Travelling at 28-30 knots we were able to keep up, but only just. Had the sea state been anything other than flat then we would have been left trailing in their wakes.

Aside from the pure spectacle, some of the detail as to how these boats behave at high speed is fascinating. What struck me first was how big the course alterations were to keep the heel of Ainslie’s boat under control. Just a slight puff of 2 knots is all it takes to warrant a huge bear away to ensure the beast can stay upright and accelerate. Indeed, the fact that these boats accelerate so fast brings the apparent wind forward in a heartbeat and demands such a big course alteration. Anticipating these gusts is crucial if the boat is to remain the right way up, such is the power in their sail plans. Feeling the gust on the back of your neck, as most of us would before committing to a bear away, is likely to be too late. Do this and you’ll be feeling water on your face shortly afterwards as the bows bury precariously and kick off plumes of steam like spray.

Interestingly Spithill’s smaller sail plan appeared to provide a more stable configuration that required less aggressive course alterations yet without any apparent loss in performance. Indeed, by the end of the 19minute, 8 mile run Spithill had taken the lead.

Clearly, without knowing what the team were testing and what configuration the boats were in it is impossible to conclude much from this display, but as the boats headed back upwind on the next round of testing there were a number of issues that had struck me already.

1 – How powerful these boats are. Even in just 12 knots of breeze you can see how their giant wing masts are twisted off at the top. I’m told that there is so much power in the wing that teams find themselves twisting off the top in most conditions simply to keep them from being overpowered. Some even over rotate the top to leeward to create additional righting moment by levering the rig to windward.

2 – How stressful sailing these cats is. They are constantly on the boil where the slightest gust can light the blue touch paper whether you want to or not.

3 – That close racing is possible and when it happens will provide some spectacular scenes. At present the San Fran dockside chat is that the two boat training between Luna Rossa and Emirates Team New Zealand is frequently a one sided affair with the Kiwis having to wait for the Italians to catch up after most runs.

4 – How quickly Ainslie has stepped up to the task of driving one of these intimidating foiling monsters. During a quick chat the day before he told me that this would be his fourth day aboard a 72 before going on to describe the helming experience as being like playing a game of Nintendo. Like F1 racing drivers, the helmsmen have push button controls to adjust the pitch of the foils and control the ride height while helming the boat. ‘Its not always a smooth process,” he told me.

5 – As the Cup fraternity starts to recover from the distress of the Artemis tragedy it is clear that the event is not out of the woods by a long way. Everyone is still extremely nervous about the prospect of another capsize. You can feel it around the team bases before they go sailing each day and there appear to be plenty of crew who will admit in private that every day afloat is a stressful one. I’m told that only last week both the Kiwis and Oracle came perilously close to capsizing.

6 – San Francisco is a particularly demanding and at times nerve wracking place to sail. Strong winds, fast running tides and a runway that feels very small at 30+ knots, as one insider told me, ‘these may be the right boats but they’re in the wrong place. Put them in the Med and you might take some of the pressure off.’
Another said, ‘Despite the huge size of the sailing area, every time you leave the dock you do so in the knowledge that in a maximum of 10 minutes you will have to tack or gybe. That’s not always convenient in these boats!’

7 – That the learning curve is still steep for all and that come the racing we could well see some major changes in the sail configuration, particularly in the gennaker department. These boats are proving so potent downwind that it is unlikely that they will set gennakers ever. Ditching these sails means that deck layouts can be re worked and manoeuvres simplified. Luna Rossa has already taken their bowsprit off and I expect the others to do the same.

And finally, that despite one of the bumpiest and traumatic roads to a modern America’s Cup, where the more usual tactical disputes and crossfire between competitors has only just got under way, come September at least, the 34th Cup promises to be a spectacular affair.