Mack Rutherford, a British-Belgian 17-year-old, landed in Bulgaria on Wednesday to become the youngest person to fly solo around the world.

Five months and a day after taking off from Bulgaria in March, Rutherford returned to the small airport near the town of Radomir, an hour from the capital Sofia, to claim his record.

"I am trying to show with this trip that young people can make a difference, just follow your dreams," the teenager said after landing.

"I am not sure there are any other records I want to break at all, I just want to go back to school to catch up," he added.

Dressed in an airman's suit, with his dark curly hair tamed by a blue cap, the slight teenager voiced regret that the adventure was over, describing a "definite sense of freedom when you are flying".

Rutherford comes from a line of pilots. His family boasts four generations of flyers, and Mack got his first taste of being at the controls when he was just seven.

His record-breaking flight covered 54,000 kilometres (34,000 miles) in 221 hours of flying time across 30 countries.

He had to face temperatures of up to 48 degrees, not least during the many hours spent waiting for overflight authorisations.

His solo ordeal also included a forced landing on the uninhabited island of Attu, west of Alaska, due to strong winds.

- Ukraine war changed plans -

His sister and parents, who were at the Radomir airport to greet the young aviator, also said his food supply had become soaked with fuel at one stage, forcing him to make do with some chocolate cakes.

Even before Rutherford took off in March, his preparations were upended by Russia's invasion of Ukraine, forcing a change in the flight path.

Instead of flying over Russia, Rutherford diverted south through Pakistan, India, South Korea and Japan before flying for 10 hours over the Pacific Ocean to reach the United States: "The most difficult stage," he said.

"This kind of journey requires a lot of control at all levels, you have to be able to control your emotions, your stress," his mother, Beatrice de Smet told AFP.

"He did it like a boss," said Sam Rutherford, the adventurer's father and a retired military pilot.

Mack Rutherford's feat was recognised by the Guinness World Records group, with a certificate confirming that he had beaten the record set last year by 18-year-old Travis Ludlow of Britain.

He also achieved the feat in an ultralight aircraft, taking the record from his sister Zara as the youngest pilot to do so.

A good loser, Zara said she was "very happy" for her brother.

She remains the youngest woman to complete a solo round-the-world flight, which she did at the start of the year at the age of 19.