Despite a £5m security operation to keep protesters away from the presidential party, the paraglider flew past police snipers and in front of the hotel, trailing a banner reading "Trump: well below par #resist".
Greenpeace said it had informed police about the stunt 10 minutes before the glider arrived.
Detective Inspector Stephen McCulloch said: "We are investigating a breach of the air exclusion zone over Turnberry Hotel, which is a criminal offence".
The incredible incident took place moments after Mr Trump arrived at the resort in Ayrshire, with flying protester branding him "well below par" - a popular golf reference.
Among the placards carried by campaigners in George Square were messages against the United States president's policies including "Give the weans Irn Bru not iron cages" while others urged him to go home, with signs saying "Bolt ya rocket and make Scotland great again".
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In a statement on the website Wilshere said, " It feels good, it feels special ". Let us know in the comment section below.
The visit was met with massive protests across the U.K, with tens of thousands congregating in central London. It is 6.5m tall and was bought with crowd-funding Image caption There was even a Trump coconut shy at the protest Image caption Armed police were at Carnival of Resistance in The Meadows Image caption Froydis Fossli Moe, said: 'I came here to show my support to the leftist part of society.
"We agreed today that as the UK leaves the European Union we will pursue an ambitious US-UK free trade agreement", she said.
Meanwhile a 20ft inflatable "Trump Baby" - an unflattering model of the president wearing a nappy - was blown up outside parliament.
"But personally, I don't think we should have been rolling out the red carpet for Donald Trump".
"I don't think anything gets the message across to Trump, but I hope demonstrations like these encourage people in the States to fight the Trump regime", he said.
At Turnberry, protesters climbed a hill to ensure the president could see them as they shouted: "No Trump, no KKK, no racist U.S.".
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The wing-back then whipped it into the corridor of uncertainty where Thomas Meunier had ventured into to tap it in. Kevin De Bruyne ( Belgium): How England desperately need a player like the Manchester City magician.
Aides had said Mr. Trump would spend the weekend preparing for Monday's meeting with Putin.
At a press conference later in the grounds of the PM's country residence, Mr Trump insisted he "didn't criticise" the Prime Minister and hit out at "fake news".
Trump participated in the North Atlantic Treaty Organisation summit in Brussels, Belgium, this week before continuing on for meetings with Prime Minister Theresa May and a first meeting with Queen Elizabeth II in the U.K. He is in Scotland for two days before heading to Helsinki, Finland, for bilateral meetings with Putin.
Protestors on the A77 protest against the visit by US President Donald Trump and first lady Melania Trump, near Turnberry, Scotland, Saturday July 14, 2018.
Zainab Hussnain, 21, from Edinburgh, said she painted "Dump Trump" on her face and joined the protest after seeing children in cages on TV.
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When the final whistle blew, the Croatians ran straight to their fans, jumping into the sea of red and white. Croatia take on England in the second semi-final of the World Cup.