Narrative:

While on climb out to practice instrument approachs, smoke came into the cabin from under the right panel. We immediately made a contact approach back to the runway. Cause: a loose defroster duct allowed smoke off the manifold to enter the cabin. Oil had dripped on the manifold during preflight inspection of the oil level. Corrective actions: the loose clamp was only detected by an a&P after the flight. The defroster's poor performance should have been a clue that something was not correct. The pilot's and instructor's relative experience did not detect this. Although no rules were violated, this distraction could have led to loss of control by distraction in low IFR conditions. I hope this helps other pilots be more aware of having a more complete emergency plan prior to flight.

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Original NASA ASRS Text

Title: PA28 PLT EXPERIENCED SMOKE IN THE COCKPIT DURING CLBOUT.

Narrative: WHILE ON CLBOUT TO PRACTICE INST APCHS, SMOKE CAME INTO THE CABIN FROM UNDER THE R PANEL. WE IMMEDIATELY MADE A CONTACT APCH BACK TO THE RWY. CAUSE: A LOOSE DEFROSTER DUCT ALLOWED SMOKE OFF THE MANIFOLD TO ENTER THE CABIN. OIL HAD DRIPPED ON THE MANIFOLD DURING PREFLT INSPECTION OF THE OIL LEVEL. CORRECTIVE ACTIONS: THE LOOSE CLAMP WAS ONLY DETECTED BY AN A&P AFTER THE FLT. THE DEFROSTER'S POOR PERFORMANCE SHOULD HAVE BEEN A CLUE THAT SOMETHING WAS NOT CORRECT. THE PLT'S AND INSTRUCTOR'S RELATIVE EXPERIENCE DID NOT DETECT THIS. ALTHOUGH NO RULES WERE VIOLATED, THIS DISTR COULD HAVE LED TO LOSS OF CTL BY DISTR IN LOW IFR CONDITIONS. I HOPE THIS HELPS OTHER PLTS BE MORE AWARE OF HAVING A MORE COMPLETE EMER PLAN PRIOR TO FLT.

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.