HAMILTON, Bermuda (Reuters) - America's Cup racing is fast, furious and dangerous.
And for Iain Murray, the man running the event, the key to making the 35th America's Cup a success has been to have the rules spelt out in "black and white" before crews even took to the crystal-clear waters of Bermuda.
That means reams of protocols and instructions that can be understood and adhered to by competitors, reducing the need for "subjective" decisions.
The umpires are also using a state-of-the art combination of GPS, electronics and graphics to ensure decisions are accurate.
"Essentially, it's the same technology that sends a missile into someone's lounge room," Murray told Reuters on Friday at Bermuda's Dockyard, where the America's Cup finalists Emirates Team New Zealand and holders Oracle Team USA will resume battle for international sport's oldest trophy this weekend.
The regatta director has had some tough calls to make.
"The hard one here has been the upper wind limit ... the day it came into question was the day that New Zealand capsized. For some people, it was my fault, but the rules had been modified a week before to actually lower the wind limits and to make it very clear," he said.
The New Zealand crew "pitch poled" - making a spectacular high-speed forward capsize - just before they were about to start a semi-final against Britain's Land Rover BAR (Ben Ainslie Racing) boat.
Some of the six crew were plunged into the water and others left clinging to the upended hull of their 50-foot (15-metre) foiling catamaran.
The capsize brought back memories from San Francisco in 2013, when Andrew "Bart" Simpson was killed in a similar incident.
"It's the same issue we went through in San Francisco after the fatality of Bart," said Murray, who was a friend of the British Olympic gold medal sailor.
Murray was the official who had to come up with a safety plan immediately after Simpson's death that would convince the coastguard to allow the competition to continue.
The boats have evolved since 2013. They are smaller and "much more robust", and safety has been a major preoccupation for all the teams and the America's Cup organisers.
"These are top-end boats, and in the wrong hands, they can be dangerous. They go fast, and when they go wrong, situations can get bad," Murray said.
"These guys are the best sailors in the world and they have worked for years to sail these boats and develop the systems on their boats. They don't want to crash their boats, they don't want to capsize. You won't win races doing that," he added.
"The difficulty is when they fall off the front or fall underneath ... that's the world of foiling sailing boats."
In recent decades foils - slender underwater "wings" that can lift a speeding vessel out of the water, minimising its drag - have become ubiquitous in racing sailing.
Murray's right-hand man Richard Slater, who is chief umpire at the event, has also had some tough calls to make during the racing leading up to the America's Cup final.
Slater was on the receiving end of some vocal protests by Artemis Racing's Team Manager Iain Percy during the Swedish team's semi-final races after imposing penalties on them, but said that was to be expected given the intensity of racing.
"You're dealing with the heat of the battle and that's one thing, as umpires, you have to remember," Slater told Reuters, adding that the sailors were in the "red zone" physically and this was bound to result in them reacting strongly to decisions.
The umpires are armed with a graphics system called "UmpApp", which allows them to make calls based on information that is accurate to millimetres and milliseconds, and are focused on that to make sure they make the right call quickly.
"If anything, when he was yelling at us we weren't even listening at that point," Slater said, adding that the teams have access to the same information within seconds, so that they can see why a decision has been made.
"UmpApp is kind of like a game," Murray said, saying it was easy for the younger sailors to get their heads around.
Editing by Andrew Roche