Narrative:

Upon arrival at aircraft for flight; noticed strong odor of oil in the cockpit and throughout the aircraft. Started APU and ran packs and smell cleared up for the most part. Notified maintenance with a write-up and were told that there had been a recent APU change and there was possibly some oil in the ducting and that it would clear out. After takeoff; all seemed well until we were at about FL200 when the purser called and said there was some smoke in the business class area; and they were investigating and would keep us informed. A few mins later; passing high 20's; he called and said there was a lot more smoke in the cabin. Captain asked for a cart and guard at the door so he could open it and look for himself. He looked and said you could not see through the cabin and there was no question we were going back. We immediately informed ATC that we wished to return and they responded by leveling us and almost immediately got us turned around. I called dispatch and informed them of our intentions and he said he would notify operations. No emergency was declared as we both felt with the flight attendant input that it was a result of the oil in the ducting but nothing more. All went smoothly and we were expeditiously brought back to the airport and given a gate when asked; instead of a stand; so we could get the passenger off. Emergency vehicles were standing by but were not requested or needed. A flight attendant had needed to use oxygen but felt better at landing and no one needed attention. At no time did we experience smoke in the cockpit.

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Original NASA ASRS Text

Title: A B777 BUSINESS CLASS CABIN FILLED WITH SMOKE AFTER TKOF. THE FLT RETURNED TO LAND. APU OIL IN A/C DUCTING WAS SUSPECTED.

Narrative: UPON ARR AT ACFT FOR FLT; NOTICED STRONG ODOR OF OIL IN THE COCKPIT AND THROUGHOUT THE ACFT. STARTED APU AND RAN PACKS AND SMELL CLRED UP FOR THE MOST PART. NOTIFIED MAINT WITH A WRITE-UP AND WERE TOLD THAT THERE HAD BEEN A RECENT APU CHANGE AND THERE WAS POSSIBLY SOME OIL IN THE DUCTING AND THAT IT WOULD CLR OUT. AFTER TKOF; ALL SEEMED WELL UNTIL WE WERE AT ABOUT FL200 WHEN THE PURSER CALLED AND SAID THERE WAS SOME SMOKE IN THE BUSINESS CLASS AREA; AND THEY WERE INVESTIGATING AND WOULD KEEP US INFORMED. A FEW MINS LATER; PASSING HIGH 20'S; HE CALLED AND SAID THERE WAS A LOT MORE SMOKE IN THE CABIN. CAPT ASKED FOR A CART AND GUARD AT THE DOOR SO HE COULD OPEN IT AND LOOK FOR HIMSELF. HE LOOKED AND SAID YOU COULD NOT SEE THROUGH THE CABIN AND THERE WAS NO QUESTION WE WERE GOING BACK. WE IMMEDIATELY INFORMED ATC THAT WE WISHED TO RETURN AND THEY RESPONDED BY LEVELING US AND ALMOST IMMEDIATELY GOT US TURNED AROUND. I CALLED DISPATCH AND INFORMED THEM OF OUR INTENTIONS AND HE SAID HE WOULD NOTIFY OPS. NO EMER WAS DECLARED AS WE BOTH FELT WITH THE FLT ATTENDANT INPUT THAT IT WAS A RESULT OF THE OIL IN THE DUCTING BUT NOTHING MORE. ALL WENT SMOOTHLY AND WE WERE EXPEDITIOUSLY BROUGHT BACK TO THE ARPT AND GIVEN A GATE WHEN ASKED; INSTEAD OF A STAND; SO WE COULD GET THE PAX OFF. EMER VEHICLES WERE STANDING BY BUT WERE NOT REQUESTED OR NEEDED. A FLT ATTENDANT HAD NEEDED TO USE OXYGEN BUT FELT BETTER AT LNDG AND NO ONE NEEDED ATTN. AT NO TIME DID WE EXPERIENCE SMOKE IN THE COCKPIT.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.