Mr Entwistle said his son, who was wearing a sunflower disability lanyard and had a diagnosis letter, shouted the word “bomb” several times when they arrived at the gate.
As they tried to board the flight, a manager wearing a BA lanyard denied the family entry and, in a video of the confrontation, said: “We are not refusing him because he’s got a disability. We are refusing him because there’s been a threat made that he has a bomb in his bag.”
She added: “Sir, today you’ve been refused travel only based off of security and the safety and welfare of other customers, yourselves, and our cabin crew … because of the threats made on multiple occasions up at the gate and down at the aircraft. We have to take it incredibly seriously.”
Mr Entwistle later told The Sun: “He was literally on the floor crying – apologising to everyone.
“It’s horrendous. I’m not a very emotional person, so to speak. But, you know, my wife was in floods of tears, my daughter was in floods of tears.”
‘He deserves to go on holiday’
Armed police escorted the 13-year-old boy out of the airport with his father and mother, Gemma Entwistle, 36, as well as his one-year-old sister, Ariella.
They spent the night in a hotel before paying £2,400 for new flights with Vueling on Sunday.
The couple’s 16-year-old daughter was permitted to board the flight with her friends.
Mr Entwistle added: “My wife and son just wanted to go home. The only reason I rebooked the flights is because I want to teach him that he can do whatever he wants.
“I don’t want him thinking ‘I can never go on holiday’. It’s about principle. I want to take him on holiday, he deserves to go on holiday.”
The family has also said it hoped BA staff would learn lessons from the incident.
The BA spokesman added: “Due to a number of contributing factors, the decision was made not to allow the group to travel on the flight.”