Mark Orams: Seven reasons this year's America's Cup is utterly unpredictable

Days out from the America's Cup in Bermuda, yachting aficionados and pundits are offering their views on favourites and finishing positions. This is just wild speculation and guess work because this America's Cup is the most wide open in history.

Here's why:

1. We have a brand new class of yacht, the AC50 full-foiling catamaran. No team has raced these yachts in any official regatta before. Practice racing is just that - it does not simulate real racing where the points matter and your opponent is focussed on beating you as opposed to testing their speed, systems, set up and options. The pressure which comes with real racing is different and teams and individuals handle this differently.

2. We are still early on the "learning-curve" with the AC50, teams have only been sailing these yachts for months not years, and are still discovering how to get the best out of them. We will see mistakes and break-downs, and big gains. A major factor will be which team can learn and develop the fastest - it's all about continual improvement. Balancing this priority with the important issue of winning enough races to stay in the competition will be critical.

3. These yachts are so fast that small mistakes will be really costly. When yachts are travelling at 40 knots-plus, a minor issue such as coming off the foils during a manoeuvre will result in hundreds of metres lost to opponents.

4. The speed of these yachts means they will separate and close in on each other very quickly. So yachts could, in 20-30 seconds, travel to opposite sides of the course and pick up different wind/wave/current conditions which may give them a significant advantage.

5.These yachts are so efficient in their "use" of the wind that they leave a lot less wind turbulence in their wake. The old-style America's Cup yachts travelled slowly and generated a lot of turbulence behind them - this made it much easier for the leading yacht to control the following one by creating "dirty-wind" which curtailed its speed. These standard covering tactics used in more than 150 years of America's Cup match-racing meant the yacht which won the start and was first around the first mark almost always won. That position of control was usually too difficult to overcome. Not so with these new AC50 catamarans - stand by for plenty of successful attacks from behind.

6.There are issues beyond the control of the competitors. This is true for all yacht racing, but on these AC50 catamarans the impact of catching a piece of weed or a plastic bag around the foils or even worse, hitting a sea-turtle (yes, this is a risk in this venue) could be devastating. These yachts are on the edge - any small object, turbulence or interference (such as waves from spectator craft for example) could have a dramatic and potentially race-losing impact.

7. The talent on these yachts is amazing. This regatta is stacked with sailing's elite. They are better than good with every trick, manoeuvre and option at their disposal. These people love to win. More importantly, they hate losing with a passion and will do everything they can - on and off the water - to avoid defeat.
Throw in the sheer speed of these yachts, and you have the most open - and exciting - America's Cup, ever. I can't wait - bring it on!!

* Professor Mark Orams, from the AUT, is NZME's resident America's Cup expert during the regatta. His contributions will include the daily racing blog. Prof Orams has been a top sailor and coach, and was involved on the weather programme in two Team New Zealand cup campaigns.