Passengers filmed the man standing up in the middle of his aisle and reading aloud on his phone as the Aer Lingus flight to Dublin was preparing to leave.
"We have two generations of human civilisation left if we carry on doing what we're doing", the unidentified man said, holding up a smartphone. The plane underwent a full security check before leaving at 11.16am local time.
"By non-violently shutting down this airport, in homage to the style of the Hong Kong democracy protesters, we are demonstrating the utter frailty of the transport systems that countries such as ours, unwisely, have come to depend upon", said an Extinction Rebellion spokesman, Rupert Read, according to The Guardian.
Videos showed the man, identified by the group as para-athlete James Brown, lying on the British Airways aircraft for over 20 minutes as authorities attempted to help him down.
A partially blind climate activist was busted Thursday afternoon at a London airport for clambering atop a British Airways plane, the Evening Standard reported.
To applause from an audience of Labour activists he said: Those women that stood up for the right of women to vote, the suffragettes, were condemned mercilessly by nearly every newspaper int he country, and they are now on postage stamps. While some protesters got inside the terminal building, flights were continuing, though some were delayed.
The environmental protests have been taking place in cities around the world.
The protest proceeded down Pearse Street onto Tara Street and then cross the river going around the Customs House to make its way to the Extinction Rebellion camp at Merrion Square via Lombard Street and Westland Row.
Aer Lingus said that a passenger was removed from the flight to Dublin due to "disruptive behavior on board".
Two women had earlier been arrested as they arrived at the scene, a witness said. "I managed to get on the roof".
Extra security measures at the airport meant that most of the protesting happened well away from the runway.
"Any assembly linked to the Extinction Rebellion "Autumn Uprising" and those linked to it who wish to continue their assembly MUST go Trafalgar Square and only assemble in the pedestrian area", it said.