A long distance swimmer on a mammoth global charity challenge is one step closer to the finish line after completing his latest channel crossing in Los Angeles.

Andy Donaldson, 31, has already completed five of the world’s toughest channel crossings, and smashed the Catalina Channel swim earlier this week.

The swimmer, originally from West Kilbride, broke a new British record with a time of nine hours and 22 minutes to cross the 32.5km route across the body of water.

Andy revealed he was even joined by some friends as he neared the end of the American crossing.

He explained: “The water was like glass out there, although there were some really tough cross-currents beneath the surface.

“As we neared the shore, a huge pod of dolphins swam alongside cheering us on, but nothing could beat the noise coming from my team on the boat.

“It was electric, and they helped carry me to the end of the crossing when everything was hurting.”

The swimmer is hoping to raise $100,000 for mental health charities as he swims seven of the world’s hardest crossings.

He is now turning his focus to the final crossing, when he will tackle the 20km Tsugaru Strait in Japan.

Andy said: “I'm really proud of the effort there, especially having not been 100 per cent in the days leading up to the swim.

“Out there on the water, I couldn't have given that anything more so I have come away very happy. It is now time to rest up, recover, and start getting ready for the final leg of this journey.”

Andy has raised tens of thousands of dollars so far to benefit the Black Dog Institute, which undertakes studies around the world to better understand mental health.

He now holds the British record for the English Channel, North Channel and Gibraltar Strait, alongside the world record for the Cook Strait in New Zealand.

He has also taken on and completed the Molokai Strait in Hawaii, his longest swim of the lot at 15 hours.

You can donate at www.teamblackdog.org.au/fundraisers/oceansseven.