Passengers on board a flight from Edinburgh to London City Airport had to make an emergency exit following a suspected engine fire.
The passengers were taken off the London-bound aircraft
One passenger reported seeing flames shooting out of an engine on the aircraft as it prepared for take-off on Wednesday morning.
He described the situation as chaotic and said he left the aircraft via an emergency chute. No-one was hurt.
An investigation has been launched into the alert on flight BA8703.
The 0800 GMT CitiExpress flight to London had been taxiing to the main runway at Edinburgh for take off when the emergency happened.
Businessman Alasdair Morton said there was a power failure in the middle of the pre-flight safety briefing.
"As it came back on the second time I noticed some flames coming from the right hand engine," he said.
"I wasn't for hanging around so I got up straight away and went through the evacuation procedure down the chute. I was the first one off the plane."
Mr Morton said he was concerned that some passengers did not realise it was a real emergency.
Alasdair Morton said there was some confusion
"It was a bit chaotic," he went on.
"Some people were taking their bags from the overhead lockers and getting their coats, but I just got out and left everything there because the plane was full of fuel.
"When we got down the chute there was no-one there to take us further away from the plane.
"I suppose that was a bit of a risk, lots of passengers within 20m of a plane which had a report of engine on fire."
A British Airways spokesman said: "Eighty-six people were evacuated from a plane at Edinburgh Airport after a member of ground crew spotted something which gave cause for concern.
"The captain acted in the most appropriate manner by immediately shutting off the engines and evacuating the passengers. We are investigating whether this was caused by an engine fire."
Alternative travel arrangements were being made for the passengers while checks were carried out on the BAe Avro RJ 100 plane.