Prince Harry flew commercially on British Airways as he spent the first night away from baby Archie to attend a charity polo match in Rome.
One passenger said she noticed the Duke of Sussex at the front of the jet sitting next to a security officer.
The new father went to Rome to support his Sentebale charity to raise funds and awareness for the organisation’s work supporting children and young people living with HIV.
Prince Harry was photographed onboard a British Airways flight from Rome to London earlier this week after he had attended a polo match which was organised to raise money for his charity Sentebale which supports young people in Africa living with HIV and AIDS
Prince Harry and his security officer were sitting at the front of the British Airways jet during the flight from Rome to London
Any eyewitness said Prince Harry went and thanked the flight crew after the aircraft landed safely at London Heathrow airport
Harry’s trip to Rome was the first night he spent apart from his new son Archie, pictured here with his wife Meghan in St George’s Hall, Windsor Castle
Prince Harry, left, played alongside Nacho Figueras, right, at the Roma Polo Club
Amy Garrick, who was on the flight said: ‘I haven’t had anything worth sharing, but this morning leaving Rome I got up to use the bathroom and I had to wait.
‘As I’m standing there, I look over and see a guy who looks like Prince Harry. And he has a wedding ring on and looks very tired.
‘The guy next to him looks like security and is glaring at me.
‘Finally I realise, it is Prince Harry on the way back to London from Rome.
‘He was at a polo tournament. He politely smiled and said hi when he realised I knew who he was. I tried to get a photo as he got off the plane. I didn’t want to harass him.’
Professional polo player Nacho Figueras, who captained Harry’s team, said the duke had begun a ‘very exciting part of his life’ with the birth of his son, and after resting had been ‘excited’ ahead of the match.
In the foreword to the Sentebale Polo Cup programme, Harry said the fight against Aids was being hampered by the stigma associated with the disease, which stopped young people being tested and others taking up the drugs and care on offer.
Mr Figueras, who was a guest at Harry’s wedding, was asked how the duke was coping with a new baby, born on May 6, and replied: ‘He’s doing great.’
The annual polo event has so far raised more than £6million for Sentebale since it was first held in Barbados in 2010
He added: ‘I just saw him, he’s ready for the game and had a good night’s sleep, so we’re excited about being able to do a great job today for Sentebale, which is why we’re here.
‘Being a father always changes you, he seems to be very, very happy, I think this is a very exciting part of his life. He was ready for it and I think he’s loving it.
‘I always thought that he would be an amazing father because he has a great affinity for children – two weeks is very, very soon, but I’m sure he’s changed.’
Harry left his wife Meghan and his baby son behind to fly out a day ahead of the match, and spent Thursday practising at the venue, the Roma Polo Club.
The annual event has raised more than £6 million for the work of Sentebale since it was first held in Barbados in 2010.
Sentebale was founded by the duke and Lesotho’s Prince Seeiso in 2006, to help the most vulnerable children and young people in Lesotho, Botswana and more recently Malawi get support to lead healthy and productive lives.
Harry and Seeiso said in their foreword to the official match programme: ‘There has been great progress made worldwide in combating the Aids epidemic but HIV remains one of the leading causes of death for adolescents in sub-Saharan Africa.
‘Three out of four new HIV infections in 15 to 19-year-olds are among young women.
‘Stigma is a major factor preventing young people knowing their HIV status and accessing life-saving treatment and care.
‘Since 2006 we have been working hard to deliver programmes that help the most vulnerable children in Lesotho, Botswana and more recently Malawi get the support they need.’