Narrative:

The C152 I train out of generally has an exhaust smell when the cabin heat is on. My instructor said it was normal so I usually ignore it. On the date of the event; I was flying with an instructor to do patterns. After doing the first touch and go; my instructor asked if I smelled any exhaust smell. I said I did; but I thought it was normal. A few seconds later my instructor noticed smoke in the cabin (but I didn't); so he took over controls; did a 180 and made a short landing. After taxiing to a parking spot; I got out of the plane and my instructor ran the plane to full power; and I noticed smoke coming out the bottom of the plane. After cutting the power and the mechanic drove over; he pointed out that the engine hull was cracked; and dripping engine oil onto the exhaust; causing the smoke.contributing factors was (according to the mechanic) probably that the engine was in warranty to 100;000 hours and it was at 130;000 hours; and the crack was due to engine fatigue.my main problem was that I didn't recognize there was anything wrong with the engine even after the plane was landed because (1) I didn't think the exhaust smell was out of place and (2) I didn't notice smoke. If the instructor wasn't around I probably wouldn't have known anything was wrong until the engine actually caught on fire.

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Original NASA ASRS Text

Title: A student pilot reported that while training with a flight instructor in a C152; smoke was observed in the cabin. After the instructor performed a precautionary landing; oil was discovered to be leaking from a crack in the engine case.

Narrative: The C152 I train out of generally has an exhaust smell when the cabin heat is on. My instructor said it was normal so I usually ignore it. On the date of the event; I was flying with an instructor to do patterns. After doing the first touch and go; my instructor asked if I smelled any exhaust smell. I said I did; but I thought it was normal. A few seconds later my instructor noticed smoke in the cabin (But I didn't); so he took over controls; did a 180 and made a short landing. After taxiing to a parking spot; I got out of the plane and my instructor ran the plane to full power; and I noticed smoke coming out the bottom of the plane. After cutting the power and the mechanic drove over; he pointed out that the engine hull was cracked; and dripping engine oil onto the exhaust; causing the smoke.Contributing factors was (according to the mechanic) probably that the engine was in warranty to 100;000 hours and it was at 130;000 hours; and the crack was due to engine fatigue.My main problem was that I didn't recognize there was anything wrong with the engine even after the plane was landed because (1) I didn't think the exhaust smell was out of place and (2) I didn't notice smoke. If the instructor wasn't around I probably wouldn't have known anything was wrong until the engine actually caught on fire.

Data retrieved from NASA's ASRS site 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.