Narrative:

While cruise climbing through 17000 ft; we received a master caution fire loop alert recognizing 'B' loop only; 5 seconds later a consequential 'a' loop then fire warning; left engine. After silencing the bell and reducing power to level at FL180; the fire light went out and the captain decided for me to continue flying the aircraft. We decided because of the warning to declare the emergency and return to ZZZ. The captain completed all pertinent checklists; notified company of the situation to return to ZZZ under emergency authority/authorized. The landing was made uneventful; stopping on the runway; then shutting down the engine; then to allow crash fire rescue equipment to read an infrared read of the left engine temperature. After a good report from crash fire rescue equipment; we continued with ATC to the gate.

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Original NASA ASRS Text

Title: AN MD83 EXPERIENCED A FIRE WARNING DURING CLB AFTER TKOF. THE CREW DECLARED AN EMER; AND RETURNED TO LAND WITH THE FIRE WARNING EXTINGUISHED WHILE THE ENG IDLED. AFTER LNDG; ENG WAS SHUT DOWN.

Narrative: WHILE CRUISE CLBING THROUGH 17000 FT; WE RECEIVED A MASTER CAUTION FIRE LOOP ALERT RECOGNIZING 'B' LOOP ONLY; 5 SECONDS LATER A CONSEQUENTIAL 'A' LOOP THEN FIRE WARNING; L ENG. AFTER SILENCING THE BELL AND REDUCING PWR TO LEVEL AT FL180; THE FIRE LIGHT WENT OUT AND THE CAPT DECIDED FOR ME TO CONTINUE FLYING THE ACFT. WE DECIDED BECAUSE OF THE WARNING TO DECLARE THE EMER AND RETURN TO ZZZ. THE CAPT COMPLETED ALL PERTINENT CHKLISTS; NOTIFIED COMPANY OF THE SITUATION TO RETURN TO ZZZ UNDER EMER AUTH. THE LNDG WAS MADE UNEVENTFUL; STOPPING ON THE RWY; THEN SHUTTING DOWN THE ENG; THEN TO ALLOW CFR TO READ AN INFRARED READ OF THE L ENG TEMP. AFTER A GOOD RPT FROM CFR; WE CONTINUED WITH ATC TO THE GATE.

Data retrieved from NASA's ASRS site as of January 2009 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.