A Wild Goose Chase?

Around the world, the ingredients of the Christmas turkey's stuffing will have remained secret once again. While a few will have tried to guess what was stuffed within the bird, others will have simply accepted whatever was inside worked.

There was a similar guessing game going on around the ViaductBasin this Christmas, but this time it was about the contents of a goose and not the festive turkey.

Since their entry into the semi finals, Oracle's goose has been a topic of conversation that has grown steadily over the following weeks. Remaining tight-lipped about the device, the team has said little about what might be inside. Several weeks later and little more is known, except that the debate seems to have sparked off a wider discussion about monitoring other boats' performances.

In a submission to the jury from a Challenger syndicate, questions were asked about the use of radar. After circulating this and other related questions to the remaining Challengers and Defender, the America's Cup International Jury issued a ruling prohibiting the use of radar or laser finders on board the yachts during racing.

The basis of their ruling was condition 19.1 of the notice of race which prohibits yachts from carrying on board while racing any equipment capable of receiving or transmitting communications or signals.

Laser range finders have been a common sight aboard some boats during the series so far, but unless the remaining Challengers and Defender can come a to a mutual agreement on the use of such devices, such equipment has been outlawed.

But what of the goose that laid the big debate? With it's white pear shaped moulding and swan neck type support it's easy to see how the nickname caught on. What's not so easy is to establish any fact about what's inside.

There have been plenty of theories from a laser beam radar, to an elaborate dummy. Some believed that the instrument was capable of seeing wind shifts further up the track, while others favoured the simpler theory that the device was conventional radar.

But shortly after such rumours started doing the rounds, Oracle spokesman Tom Ehman was quoted as confirming that the their 'goose' did not contain LIDAR or a similar system.

Instead, it was the latter theory that appeared to carry the most weight, with a mini ARPA type radar that can lock-on and track a competitor's every move, being a popular guess.

ARPA radar is used extensively aboard commercial ships and is an important tool in contributing to collision avoidance as it allows the radar operator to monitor another craft's speed and heading automatically. This would offer a significant advantage over the more popular laser range finding devices as these only give distance and relative speed and only work over a limited range. According to one syndicate sailor, the laser range finder is, 'of little practical use as it's often out of range just as the boats get well separated and the information would start to be of use. For most navigators, a hand-bearing compass is the most useful device.'

Radar on the other hand, has a much greater range.

Equally intriguing is the idea that this system could be linked to the fancy head-up display gear that Oracle's afterguard Eric Doyle was wearing at times. The official line from Oracle was that this high tech head gear was used to display the boat's own sailing information making it easier to see the numbers when other crew members are in the way.

The system is a spin off from the development work that the F1 BMW Williams team has been developing for driver/pit communication and while receiving information in the way that an F1 driver might is specifically prohibited, the technology is capable of relaying virtually any kind of navigational information.

Another theory is that a sophisticated radar system would be able to look at the position of their opponent and relate this to a sophisticated software model that could visualise both boats' position on the course. The software could then run 'what if' type scenarios.

Although pure speculation, it is easy to see the advantage of such a sophisticated computer race model in which typical scenarios, such as mark roundings or crossovers on the course, have been pre-planned into the system. The unit could then churn out a list of prioritised options. Professional though they are, according to some of the crews, in the heat of the moment it's easy to lose the plot. Focussing on a simple set of guidelines formulated ashore and away from the heat of the competition, could provide a steadying hand.

As one top navigator put it, such a list could provide a welcome 'get out of jail card'.

Yet all this may now simply be a flight of fancy following the Jury's recent ruling. If radar was in the goose to start with, it's unlikely to be there now and the idea can no longer fly.

The mass speculation surrounding the contents of Oracle's gimbaled orb could well have been little more than a wild goose chase.