We took a flight from Johannesburg to Sydney recently on Qantas Flight 64. It is operated by a 747-400 with Rolls-Royce RB211-524G-T engines.
We were sitting on the right outside window, and could see engine #4 (and none other). On taxi we noticed smoke coming from a port on the side of the engine. Swirling, not jetting. This continued during takeoff, and climbout, but obviously became a smoother stream on climbout.
It is disconcerting to see this at the start of a 12 hour flight across the Southern Ocean (Went down to 51 degree south). I assumed they knew what they were doing though...
The smoke was white, probably oil related? As the sun set pretty quick after climbout, didn't pay it a second thought. Taxiing on the ground in Sydney, the swirling smoke was still billowing out.
Was this engine burning oil? does it need a seal replacement?
Here is a good photo, on a different airline though, but same port - just under the Rolls Royce decal. http://www.airliners.net/photo/Cathay-Pa...732b0b51c77ef00http://www.gcmap.com/mapui?P=jnb-syd