Narrative:

On initial climb; started smelling an electrical fire smell. About 5 seconds later; at about 500 feet AGL; saw smoke coming into the cockpit through the vent on the dash. I turned immediately; called an emergency; and tear-dropped with power in to land on the opposite runway I had just taken off from. Once I saw I was high enough to glide in; I pulled power to idle and lowered the nose to try and put the fire out. I decided to leave the engine running as I was over a congested area with housing tracts below; and decided it would be more dangerous to try and make an emergency landing off airport than to leave engine on and fly back to airport as I was only maybe half a mile away. The smoke dissipated by the time I landed; and I taxied quickly back to the terminal where I shut down and exited the aircraft. Upon investigation and talking to the mechanics who inspected the aircraft; it turned out the muffler's back end had blown off; directing all the extremely hot exhaust gases towards the firewall; where the battery and other electrical components were; which was what started the fire. According to the mechanics; when the aircraft was bought the pre-buy inspection did not inspect the muffler well enough as there would have been cracks in the muffler; indicating a potentiality for a malfunction. I felt that my training really prepared me to deal with this emergency in a timely and professional manner. The only things I can really think of that I should improve upon was my radio communications; I spent too much time (thinking after the fact) on radio calls when I could have just said 'mayday mayday; emergency landing.' but the fact that my imsafe checklist was good; and both individuals in the aircraft were aware of emergency procedures; made this an invaluable learning experience. Also; checking the muffler is highly important!

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Original NASA ASRS Text

Title: C152 pilot reports smelling electrical fumes shortly after takeoff then seeing smoke coming into the cockpit through the vent on the dash. An emergency is declared and a tear drop turn is made back to land opposite direction on the departure runway. Maintenance discovers a failed muffler blowing hot exhaust on the firewall.

Narrative: On initial climb; started smelling an electrical fire smell. About 5 seconds later; at about 500 feet AGL; saw smoke coming into the cockpit through the vent on the dash. I turned immediately; called an emergency; and tear-dropped with power in to land on the opposite runway I had just taken off from. Once I saw I was high enough to glide in; I pulled power to idle and lowered the nose to try and put the fire out. I decided to leave the engine running as I was over a congested area with housing tracts below; and decided it would be more dangerous to try and make an emergency landing off airport than to leave engine on and fly back to airport as I was only maybe half a mile away. The smoke dissipated by the time I landed; and I taxied quickly back to the terminal where I shut down and exited the aircraft. Upon investigation and talking to the mechanics who inspected the aircraft; it turned out the muffler's back end had blown off; directing all the extremely hot exhaust gases towards the firewall; where the battery and other electrical components were; which was what started the fire. According to the mechanics; when the aircraft was bought the pre-buy inspection did not inspect the muffler well enough as there would have been cracks in the muffler; indicating a potentiality for a malfunction. I felt that my training really prepared me to deal with this emergency in a timely and professional manner. The only things I can really think of that I should improve upon was my radio communications; I spent too much time (thinking after the fact) on radio calls when I could have just said 'mayday mayday; emergency landing.' But the fact that my IMSAFE checklist was good; and both individuals in the aircraft were aware of emergency procedures; made this an invaluable learning experience. Also; checking the muffler is highly important!

Data retrieved from NASA's ASRS site as of July 2013 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.