A 17-year-old pilot has become the youngest person to fly alone around the world.Mack Rutherford, who holds British and Belgian citizenship, completed his trip Wednesday.He landed his small plane in Bulgaria’s capital, Sofia.That is also where he started his trip five months ago.Rutherford, who turned 17 during his trip, broke the Guinness World Record for youngest male to fly around the world.That record had been held by Travis Ludlow of Britain.Ludlow was 18 when he made his flight around the world last year.Rutherford also became the youngest person to fly around the world in an ultralight plane.His sister, Zara, finished her own around-the-world flight in January at age 19.Until Wednesday, she held the ultralight record.Zara also set the record as the youngest woman to fly alone around the world.His trip, which began March 23, took Rutherford through 52 countries across five continents.To set a mark recognized by the Guinness World Records, he crossed the equator twice.