A CRJ170 had intermittent EICAS and aural fire warnings during climbout. The warnings continued sporadically after landing and at the gate where the engine was shutdown using the Fire Handle.
Synopsis
A CRJ170 had intermittent EICAS and aural fire warnings during climbout. The warnings continued sporadically after landing and at the gate where the engine was shutdown using the Fire Handle.
Narrative
My crew and I departed for our first destination with 31 passengers. Every member of the crew performed all 'first-flight' preflight checks as required. Upon departure; ATC instructed us to climb to FL320. The First Officer was flying the aircraft at this time. At approximately 19;000 FT; an alarm sounded in the cockpit (and was annunciated on the EICAS) as an 'ENG 1 FIRE.' As we proceeded to start the appropriate checklists (Quick Reference Card); the indication and associated alarms disappeared. As we were trying to diagnose the problem; the alarms returned. As before; the alarms stopped within approximately six to ten seconds. Both the First Officer and I evaluated the situation. There were NO abnormal indications; there was NO loss of thrust; and other aircraft systems continued to have normal indications and operation. Because of the confusing nature of the problem and the sporadic indications of an ENG 1 FIRE; we elected to declare an emergency and return to the departure airport. Dispatch was informed of this via ACARS. I contacted the flight attendants at this time to inform them of the situation. They were provided information such as the nature of the emergency; the time to prepare; and that we would continue to evaluate the problem and determine if an evacuation would be required. We also asked them to look outside and see if any flames/smoke was visible at this time. We were informed that nothing looked abnormal. As the descent continued; the ENG 1 FIRE indication appeared sporadically as described above. No other additional indications of a fire were noticed; nor were any other aircraft systems operating abnormally. At no point did the fire indication remain illuminated for more than six to ten seconds; to the best of our knowledge. After evaluating everything that had transpired up to this point; I felt that the safest decision at this time was to continue to monitor engine number one. The controls remained guarded by the pilot flying until after landing. ATC gave us vectors for a straight-in approach. Fire equipment was standing by. Upon final approach; both engines (and all other associated aircraft systems) continued to show normal indications. The Captain took over as the flying pilot when the aircraft was established on the ILS approach. On short final; the ENG 1 FIRE indication illuminated again. A normal; flaps FULL landing was performed. The aircraft was stopped using thrust reversers and maximum braking. The flight attendants also made a 'BRACE' command prior to touchdown that was very appropriate (it was audible from the flight deck). At that point; the ENG 1 Fire handle was pulled and one fire bottle was discharged into the engine. I made a PA announcement for everyone to remain seated (I had previously told the flight attendants that I would make an evacuation command over the PA if it were required. I also stated that any evacuation would be on the right side of the aircraft.). Fire crews informed us that no fire or smoke was present and the aircraft was taxied to the gate on the number two engine. Passengers deplaned normally and without injury. The company was contacted after passengers were deplaned. It was asked if the aircraft had an overweight landing. I distinctly remember the aircraft weight being 70;000 pounds. This was checked shortly after departure; so an overweight landing did not occur. It should also be noted that after the aircraft was parked at the gate with both engines shut down (and the fire handle to ENG 1 pulled) an 'ENG 1 FIRE' indication appeared on the EICAS (this happened after the aircraft was at the gate for 15-20 minutes). The unusual actions of the ENG 1 Fire message (sporadically coming and going); coupled with other normal indications and the absence of visual indications made us think that this was an indicator/sensor problem. Reflecting on the entire situation; it would have been more prudent to shut the engine down on the first indication of a possible fire and proceed with a single-engine emergency landing.
Second reporter narrative
After departing; while climbing through FL190 for FL320 'ENG 1 Fire' associated annunciations illuminated. I was the pilot flying; the Captain initiated the QRC. Seconds later; the alarms disappeared. We both continued to analyzing the ENG for status. The alarm sounded for a second time. We declared the emergency with ATC; requested vectors back to our departure airport and initiated a descent. We still had normal thrust and all ENG indications appeared normal throughout the entire flight. The Captain informed the Flight Attendants of the situation and asked them to check the engine for smoke. None was observed. He also instructed them to prepare for the return and possible evacuation of the aircraft; if warranted; on the ground. I remained pilot flying; my entire was focused on monitoring the engine and guarding the controls. During the return the Captain coordinated for emergency equipment and the ILS approach. Once established on the approach the Captain requested the flight controls to execute the approach. We elected to do a full flap; max braking landing. We heard the Flight Attendant give the brace call upon landing. Upon reaching a full stop we discharged a fire bottle into the #1 ENG. The Captain made a PA announcement to remain seated while I coordinated with the fire department to have a fireman inspect the engine for fire. After it was determined that there was no fire; we taxied to the gate. After we had been at the gate; for several minutes; with both engines shutdown; #1 ENG fire alarm sounded again.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.