Narrative:

Just after takeoff from iah, passing through approximately 1900', the master caution/engine fire warning lights began intermittently flickering, no bell. The aircraft was leveled off and the warning lights went out. Shortly thereafter, the same intermittent warning lights began flickering again, this time bringing on the engine #2 fire light and bell. The bell was silenced, then all warnings lights went out and did not recur. All engine instruments remained normal throughout the flight. Departure control was notified of our warnings lights and intention to return to land. Emergency equipment was offered, and as a precaution was accepted. A normal but overweight landing was accomplished back at iah. No engine was secured in-flight. Total flight time was 8 mins, during which the passenger and F/a's were notified that we were returning to land. Approximately 1 1/2 hours after landing, maintenance discovered a broken pneumatic duct on the #2 engine. The aircraft's log book indicated the same problem had occurred a day prior, with the bottom fire loop being changed. No evidence of a fire was found.

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Original NASA ASRS Text

Title: ACR MLG DUCT OVERHEAT TRIGGERS ENGINE FIRE WARNING AFTER TKOF FROM IAH. RETURN LAND.

Narrative: JUST AFTER TKOF FROM IAH, PASSING THROUGH APPROX 1900', THE MASTER CAUTION/ENG FIRE WARNING LIGHTS BEGAN INTERMITTENTLY FLICKERING, NO BELL. THE ACFT WAS LEVELED OFF AND THE WARNING LIGHTS WENT OUT. SHORTLY THEREAFTER, THE SAME INTERMITTENT WARNING LIGHTS BEGAN FLICKERING AGAIN, THIS TIME BRINGING ON THE ENG #2 FIRE LIGHT AND BELL. THE BELL WAS SILENCED, THEN ALL WARNINGS LIGHTS WENT OUT AND DID NOT RECUR. ALL ENG INSTRUMENTS REMAINED NORMAL THROUGHOUT THE FLT. DEP CTL WAS NOTIFIED OF OUR WARNINGS LIGHTS AND INTENTION TO RETURN TO LAND. EMER EQUIP WAS OFFERED, AND AS A PRECAUTION WAS ACCEPTED. A NORMAL BUT OVERWT LNDG WAS ACCOMPLISHED BACK AT IAH. NO ENG WAS SECURED INFLT. TOTAL FLT TIME WAS 8 MINS, DURING WHICH THE PAX AND F/A'S WERE NOTIFIED THAT WE WERE RETURNING TO LAND. APPROX 1 1/2 HRS AFTER LNDG, MAINT DISCOVERED A BROKEN PNEUMATIC DUCT ON THE #2 ENG. THE ACFT'S LOG BOOK INDICATED THE SAME PROB HAD OCCURRED A DAY PRIOR, WITH THE BOTTOM FIRE LOOP BEING CHANGED. NO EVIDENCE OF A FIRE WAS FOUND.

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.