Narrative:

Shortly after takeoff, smoke started to enter the cockpit. We donned our oxygen masks and advised the tower that we were returning for landing and declaring an emergency. We ran all of the appropriate checklists, contacted our dispatcher, and spoke to the flight attendant and passenger. We landed without further incident and taxied the aircraft to the gate where we were met by customer service personnel, maintenance, and the fire department. This was our first flight of the trip. When we first arrived at the aircraft, maintenance was deferring the APU, so we needed an air start. The next day we found out that the cause of the smoke was from the APU contaminating the environmental system. Supplemental information from acn 541089: flight was first leg of 4 day trip. Got to aircraft and found maintenance working on APU. We continued preflight and eventually maintenance deferred APU. Captain and I decided to do a 'bleeds open' takeoff because of our light weight. Rest of ground operations normal. Upon initial takeoff, immediately after gear retraction, smoke filled cockpit. I put on my mask, took control of aircraft upon captain's direction, then captain donned his mask. I then gave control back to captain. I contacted departure and informed them we needed an emergency return to airport. The captain then took the ATC radios and flew while we cleaned up the aircraft, did normal and emergency checklists, and contacted dispatch. We were airborne approximately 20 mins, yet it seemed like 2! I spoke to the flight attendant, passenger, then took ATC radios. Landing was uneventful. We taxied to gate and did a normal egress. Subsequently, we were told that oil from APU leaked onto/into packs, which caused the smoke.

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Original NASA ASRS Text

Title: CL65 CREW HAD SMOKE IN THE COCKPIT AFTER TKOF AT CVG.

Narrative: SHORTLY AFTER TKOF, SMOKE STARTED TO ENTER THE COCKPIT. WE DONNED OUR OXYGEN MASKS AND ADVISED THE TWR THAT WE WERE RETURNING FOR LNDG AND DECLARING AN EMER. WE RAN ALL OF THE APPROPRIATE CHKLISTS, CONTACTED OUR DISPATCHER, AND SPOKE TO THE FLT ATTENDANT AND PAX. WE LANDED WITHOUT FURTHER INCIDENT AND TAXIED THE ACFT TO THE GATE WHERE WE WERE MET BY CUSTOMER SVC PERSONNEL, MAINT, AND THE FIRE DEPT. THIS WAS OUR FIRST FLT OF THE TRIP. WHEN WE FIRST ARRIVED AT THE ACFT, MAINT WAS DEFERRING THE APU, SO WE NEEDED AN AIR START. THE NEXT DAY WE FOUND OUT THAT THE CAUSE OF THE SMOKE WAS FROM THE APU CONTAMINATING THE ENVIRONMENTAL SYS. SUPPLEMENTAL INFO FROM ACN 541089: FLT WAS FIRST LEG OF 4 DAY TRIP. GOT TO ACFT AND FOUND MAINT WORKING ON APU. WE CONTINUED PREFLT AND EVENTUALLY MAINT DEFERRED APU. CAPT AND I DECIDED TO DO A 'BLEEDS OPEN' TKOF BECAUSE OF OUR LIGHT WT. REST OF GND OPS NORMAL. UPON INITIAL TKOF, IMMEDIATELY AFTER GEAR RETRACTION, SMOKE FILLED COCKPIT. I PUT ON MY MASK, TOOK CTL OF ACFT UPON CAPT'S DIRECTION, THEN CAPT DONNED HIS MASK. I THEN GAVE CTL BACK TO CAPT. I CONTACTED DEP AND INFORMED THEM WE NEEDED AN EMER RETURN TO ARPT. THE CAPT THEN TOOK THE ATC RADIOS AND FLEW WHILE WE CLEANED UP THE ACFT, DID NORMAL AND EMER CHKLISTS, AND CONTACTED DISPATCH. WE WERE AIRBORNE APPROX 20 MINS, YET IT SEEMED LIKE 2! I SPOKE TO THE FLT ATTENDANT, PAX, THEN TOOK ATC RADIOS. LNDG WAS UNEVENTFUL. WE TAXIED TO GATE AND DID A NORMAL EGRESS. SUBSEQUENTLY, WE WERE TOLD THAT OIL FROM APU LEAKED ONTO/INTO PACKS, WHICH CAUSED THE SMOKE.

Data retrieved from NASA's ASRS site as of July 2007 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.