They've been variously described as stupid, crazy and idiots, but two brothers yesterday insisted their voyage across the Atlantic on a tiny open-topped boat was not a suicide mission.

Ralph and Bob Brown's 21 foot flats boat — normally designed for shallow water fishing — was tested to the limit as they trekked nearly 800 miles from North Carolina to Bermuda in an unescorted 51-hour journey.

They arrived in St. George's on Wednesday afternoon to book themselves a place in the Guinness Book of World Records, as nobody before has ever travelled so far in such a vessel.

However, even though the trip has been dubbed The Ultimate Bermuda Suicide Challenge by the pair's publicity team, the daredevils claim the risk factor was minimal.

"People are always saying we're stupid or idiots to do this," said Ralph. 48, who built Intruder 21, "but it wasn't our idea to call it a suicide mission.

"People do much more dangerous things than this. Look at those guys serving in Iraq, that's dangerous.

"We had no problems at all. We anticipated going through waves ten to 15 feet and they didn't even come that big.

"People can't comprehend these boats can go through big waves, so we wanted to show it could cross an ocean, and we've done that.

"The suicide run was not the boat — the real suicide is what Bob's doing when he goes home and confronts his wife!"

Bob, a painter, explained he had to step in against the will of wife Jill after Ralph's intended voyage partner "chickened out" two days before the journey on the advice of his family.

"I was supposed to be going camping, so I had to call her in my lunch break to let her know there'd been a change of plan," said Bob, 49.

"She never said it was too dangerous. I think she was more concerned that I would be away from the family.

"I had a few butterflies the night before, but the boat ran fine. No sweat."

Ralph said he declined his wife Anne's offer to be his substitute partner.

"I'm not afraid of big waves, but I am afraid of her standing there screaming at me for two and a half days. I wasn't going to subject myself to that," he said.

On the trip over, the brothers, from Florida, averaged 13 mph and used 220 gallons of fuel. They took turns to leave the cockpit and were fastened to the boat by rope when they did.

They are expected to leave the Island for New York in a few days for the second leg of their journey, providing the weather is predictable enough.

Ralph said: "We're not going to set off when there's a front — we're not that crazy."

Ralph, who makes and sells flats boats, said he hopes the completion of the mission will help encourage more people to buy his vessels.

When the pair arrived on Wednesday, Bermuda Maritime Operations Centre raised concerns about the perils of tackling the ocean in a small open-top boat.

They advised them not to go back out to sea, but the brothers have stressed their determination to continue regardless.

"We were concerned about the size of the craft — it's quite small and quite open as well. We asked them what would happen if it took water on board," said a Maritime spokesman.

"But we can't stop them from going back out. We have chatted about their safety on board and we will make sure we keep an eye on them."