The woman was abroad the XiamenAir flight as it was about to take off from the runway at Beijing Capital International Airport in China.
Other passengers on the Boeing 757 claimed the woman flipped the lever to deploy the inflatable emergency slide despite being told not to.
She was sitting two rows behind the emergency exit door on the left hand side at the time.
The woman was immediately restrained by flight attendants, with the situation forcing the plane to be severely delayed.
According Chinese media site Weibo, the woman deployed the slide at 11:50am, just seconds after cabin crew warned over the PA system against touching any of the emergency equipment.
The plane had to be inspected from top to bottom after the slide was restored.
After being removed from the flight, the passenger is now at the hands of Chinese tourism authorities.
She faces a possible travel ban pending an investigation into the incident.
It’s believed the man has a pregnant fiancee who was at home at the time.
The pair – who reportedly met that evening – were on a flight from Manchester to Ibiza when the incident unfolded.
Passengers have claimed that crew did nothing to break up the romp, even after one woman asked if she could move seats.
Ryanair said it is looking into the incident but does not tolerate “unruly behaviour”.
