Narrative:

While in level cruise at FL330, right engine detector b-loop light came on and we complied with pilot handbook. A few mins later the loop a light for left engine came on, followed by a full fire warning on the right engine. While the captain and I considered our immediate actions, the left engine fire warning activated. At this point we both concurred that the warnings had to be false (no other indications of fire), and we declared an emergency while diverting to knoxville. A safe landing was made, and we stopped on the runway to allow crash crew to verify no indication of fire in either engine. No fire was evident, and we taxied to a gate. After shutdown, both fire lights remained on for about 30 mins. In 20 yrs of flying, this was truly one of the roughest emergency sits I have faced. Had we immediately complied with the memory items for an engine fire on right engine, we would have shut it down and been on APU generator only at night (left engine generator was on MEL with CSD disconnected). Then, the left engine fire warning would have been staring us in the face a few mins later. As a former navy pilot, I am a firm believer in 'sitting on your thumbs' for a few mins during such an emergency, and it has paid off once again. Fortunately for me, the captain (also former military) feels the same way, and recommends that your first action in such an emergency should be to 'wind the clock.'

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Original NASA ASRS Text

Title: FLC OF AN MLG DECLARED AN EMER AND DIVERTED TO LAND AFTER HAVING FIRE WARNINGS IN FIRST ONE, AND THEN THE OTHER, ENG DURING HIGH ALT CRUISE. ACFT SUCCESSFULLY LANDED WITH EMER EQUIPMENT STANDING BY AND FOUND NO EVIDENCE OF FIRE. ALL PAX WERE DEPLANED AT THE GATE.

Narrative: WHILE IN LEVEL CRUISE AT FL330, R ENG DETECTOR B-LOOP LIGHT CAME ON AND WE COMPLIED WITH PLT HANDBOOK. A FEW MINS LATER THE LOOP A LIGHT FOR L ENG CAME ON, FOLLOWED BY A FULL FIRE WARNING ON THE R ENG. WHILE THE CAPT AND I CONSIDERED OUR IMMEDIATE ACTIONS, THE L ENG FIRE WARNING ACTIVATED. AT THIS POINT WE BOTH CONCURRED THAT THE WARNINGS HAD TO BE FALSE (NO OTHER INDICATIONS OF FIRE), AND WE DECLARED AN EMER WHILE DIVERTING TO KNOXVILLE. A SAFE LNDG WAS MADE, AND WE STOPPED ON THE RWY TO ALLOW CRASH CREW TO VERIFY NO INDICATION OF FIRE IN EITHER ENG. NO FIRE WAS EVIDENT, AND WE TAXIED TO A GATE. AFTER SHUTDOWN, BOTH FIRE LIGHTS REMAINED ON FOR ABOUT 30 MINS. IN 20 YRS OF FLYING, THIS WAS TRULY ONE OF THE ROUGHEST EMER SITS I HAVE FACED. HAD WE IMMEDIATELY COMPLIED WITH THE MEMORY ITEMS FOR AN ENG FIRE ON R ENG, WE WOULD HAVE SHUT IT DOWN AND BEEN ON APU GENERATOR ONLY AT NIGHT (L ENG GENERATOR WAS ON MEL WITH CSD DISCONNECTED). THEN, THE L ENG FIRE WARNING WOULD HAVE BEEN STARING US IN THE FACE A FEW MINS LATER. AS A FORMER NAVY PLT, I AM A FIRM BELIEVER IN 'SITTING ON YOUR THUMBS' FOR A FEW MINS DURING SUCH AN EMER, AND IT HAS PAID OFF ONCE AGAIN. FORTUNATELY FOR ME, THE CAPT (ALSO FORMER MIL) FEELS THE SAME WAY, AND RECOMMENDS THAT YOUR FIRST ACTION IN SUCH AN EMER SHOULD BE TO 'WIND THE CLOCK.'

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.