British Airways' first Boeing 787-8 has emerged from the airframer's paint facility with its engine nacelles painted in the carrier's traditional blue scheme.
The colours mark a departure from the white nacelles which have featured on virtually all 787s delivered so far, a restriction which had resulted from laminar flow considerations.
BA's 787s are being fitted with Rolls-Royce Trent 1000 engines. The carrier's original publicity material had shown the aircraft with white nacelles.
But Boeing says it is evaluating customer requests to paint the nacelles on a "case by case basis".
"We need to evaluate each custom colour request because different colours may require different thicknesses to achieve the desired appearance," the airframer says.
"We need to ensure that the thickness required does not exceed the design tolerance."
British Airways' first 787 has been photographed at the Seattle production facility with blue nacelles, in contrast to the initial artistic impressions but in keeping with the scheme on the rest of its fleet.
Boeing says that specific discussions with its customers regarding the colours are "considered confidential".
The paint is crucial to the aircraft's economics because laminar flow reduces skin friction drag, and cuts fuel burn, but it requires a smooth surface with minimal boundary disruption.
Even the thickness of paint layers can interrupt the laminar flow between the engine inlet and the surface of the nacelle.
Qatar Airways' 787s have been painted pale grey, while other carriers have retained the white nacelles.
BA has ordered 42 787s of which the first 24 comprise eight 787-8s and 16 787-9s. The carrier is awaiting notification of delivery dates for the type.