Narrative:

On wednesday I took of from ZZZ to practice some commercial maneuvers out in the ZZZ area. After finishing out my maneuvers; I decided to head back home to ZZZ. While heading back to ZZZ I called tower and notified them that I was 10 miles from the north inbound at 3;000 ft MSL with ATIS and that I request any option. I was clear for the option and was told to come in for a right downwind for runway 24. As I was turning for a right downwind for runway 24; 3 miles from ZZZ smoke appeared in my cockpit. I then proceeded on checking my wings; gauges; and all my instruments to see for any traces of flames; there were none. I then told tower; 'C152 has smoke in the cockpit; requesting a straight in for runway 6.' tower then replied to me; 'C152 will you need me to send out the fire trucks?' I then replied; 'no this is not an emergency. Smoke has appeared in my cockpit am ok and I still have control of the aircraft.' tower then replies; 'ok I am still going to send out the trucks for you and you are cleared to land on runway 6.' I landed on runway 6 and after landing; I called tower and said; 'ZZZ tower may I taxi on taxiway a and back to the west ramp.' tower replies; 'C152; no. I prefer you shut the aircraft off and let the fire department take a look at the aircraft.' I then replied; 'C152 shutting down. Thanks.'callback conversation with reporter revealed the following information: the smoke appeared in the cockpit shortly after turning on the heater. Post flight inspection revealed that oil had been spilled during servicing and had gotten into heater manifold.

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Original NASA ASRS Text

Title: C152 PLT RPTS SMOKE IN HIS COCKPIT THEN LANDS SAFELY.

Narrative: ON WEDNESDAY I TOOK OF FROM ZZZ TO PRACTICE SOME COMMERCIAL MANEUVERS OUT IN THE ZZZ AREA. AFTER FINISHING OUT MY MANEUVERS; I DECIDED TO HEAD BACK HOME TO ZZZ. WHILE HEADING BACK TO ZZZ I CALLED TWR AND NOTIFIED THEM THAT I WAS 10 MILES FROM THE NORTH INBOUND AT 3;000 FT MSL WITH ATIS AND THAT I REQUEST ANY OPTION. I WAS CLEAR FOR THE OPTION AND WAS TOLD TO COME IN FOR A RIGHT DOWNWIND FOR RUNWAY 24. AS I WAS TURNING FOR A RIGHT DOWNWIND FOR RUNWAY 24; 3 MILES FROM ZZZ SMOKE APPEARED IN MY COCKPIT. I THEN PROCEEDED ON CHKING MY WINGS; GAUGES; AND ALL MY INSTRUMENTS TO SEE FOR ANY TRACES OF FLAMES; THERE WERE NONE. I THEN TOLD TOWER; 'C152 HAS SMOKE IN THE COCKPIT; REQUESTING A STRAIGHT IN FOR RWY 6.' TWR THEN REPLIED TO ME; 'C152 WILL YOU NEED ME TO SEND OUT THE FIRE TRUCKS?' I THEN REPLIED; 'NO THIS IS NOT AN EMER. SMOKE HAS APPEARED IN MY COCKPIT AM OK AND I STILL HAVE CTL OF THE ACFT.' TWR THEN REPLIES; 'OK I AM STILL GOING TO SEND OUT THE TRUCKS FOR YOU AND YOU ARE CLRED TO LAND ON RWY 6.' I LANDED ON RWY 6 AND AFTER LNDG; I CALLED TOWER AND SAID; 'ZZZ TWR MAY I TAXI ON TXWY A AND BACK TO THE WEST RAMP.' TWR REPLIES; 'C152; NO. I PREFER YOU SHUT THE ACFT OFF AND LET THE FIRE DEPARTMENT TAKE A LOOK AT THE ACFT.' I THEN REPLIED; 'C152 SHUTTING DOWN. THANKS.'CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE SMOKE APPEARED IN THE COCKPIT SHORTLY AFTER TURNING ON THE HEATER. POST FLT INSPECTION REVEALED THAT OIL HAD BEEN SPILLED DURING SERVICING AND HAD GOTTEN INTO HEATER MANIFOLD.

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.