Two pilots were arrested on suspicion of being under the influence of alcohol as they prepared to fly a transatlantic passenger jet from Scotland to the US.
Concerns were reportedly raised over the pilots before the 9am United Airlines UA162 flight to Newark, New Jersey, was due to depart from Glasgow Airport on Saturday.
Police said the two men - aged 35 and 45 - were arrested and detained in police custody.
The flight, carrying 141 passengers, eventually took off on Saturday evening with a new crew on board.
The incident follows the appearance in court last month of two Canadian pilots charged with being drunk as they prepared to fly a passenger jet from Scotland to Toronto.
Jean-Francois Perreault, 39, and Imran Zafar Syed, 37, were arrested on Monday July 18 before they were due to take off on the Air Transat flight from Glasgow Airport.
Under the Scottish Railways and Transport Safety Act 2003, Section 93, the limit of alcohol for pilots in the case of breath is nine microgrammes of alcohol in 100 millilitres.
A spokesman for United Airlines said: "The two pilots have been removed from service and their flying duties.
According to the Independent, the two pilots are expected to appear at Paisley Sheriff Court today.