Narrative:

Shortly after takeoff; below 1;000 ft; a fire loop detection light illuminated and a burning smell was noted in the cockpit and cabin. I was the flying pilot. The captain advised me to fly the plane and work the radios while he ran the QRH and coordinated with the cabin crew. I engaged the autopilot to lighten the work load while the captain communicated twice with the cabin crew about the cabin odor; intensity; location and asked if any fumes/smoke were visible. None was visible; but the odor intensified; both in the cabin and cockpit. The captain started to run the fire loop detection checklist from the e-qrh. It was the right engine b-loop. I suggested we land to deal with the problem on the ground in case we were on fire. The captain wanted more time in flight to run the check lists and trouble shoot the problem. However; if we continued and the cabin filled with smoke or any other more severe situation would have occurred; it would have been bad for us and the company. We were already getting vectored to a right down wind for runway xxr at ZZZ. We asked to have equipment standing by; but did not declare an emergency. The tower declared an emergency for us. Once on the ground we directed emergency services to the right engine for observation; through the tower. We also coordinated with the fire department on a separate VHF frequency and received the all clear before returning to the gate. In flight; the captain had completed about 3/4 of the e-qrh procedure. He was not able to complete the fire test for the single loop. Time was a critical factor as we were returning immediately for landing. I made a soft landing at about 200 FPM vertical speed descent. It was a 130;000 pound landing weight maximum; we weighed 133;800. That was noted in the log book.

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Original NASA ASRS Text

Title: A DC9-80 flight crew elected to return to their departure airport when a fire loop detection light illuminated accompanied by a burning smell in the cockpit and cabin.

Narrative: Shortly after takeoff; below 1;000 FT; a fire loop detection light illuminated and a burning smell was noted in the cockpit and cabin. I was the flying pilot. The Captain advised me to fly the plane and work the radios while he ran the QRH and coordinated with the cabin crew. I engaged the autopilot to lighten the work load while the Captain communicated twice with the cabin crew about the cabin odor; intensity; location and asked if any fumes/smoke were visible. None was visible; but the odor intensified; both in the cabin and cockpit. The Captain started to run the Fire Loop Detection checklist from the E-QRH. It was the right engine B-loop. I suggested we land to deal with the problem on the ground in case we were on fire. The Captain wanted more time in flight to run the check lists and trouble shoot the problem. However; if we continued and the cabin filled with smoke or any other more severe situation would have occurred; it would have been bad for us and the company. We were already getting vectored to a right down wind for Runway XXR at ZZZ. We asked to have equipment standing by; but did not declare an emergency. The Tower declared an emergency for us. Once on the ground we directed emergency services to the right engine for observation; through the Tower. We also coordinated with the Fire Department on a separate VHF frequency and received the all clear before returning to the gate. In flight; the Captain had completed about 3/4 of the E-QRH procedure. He was not able to complete the fire test for the single loop. Time was a critical factor as we were returning immediately for landing. I made a soft landing at about 200 FPM vertical speed descent. It was a 130;000 LB landing weight maximum; we weighed 133;800. That was noted in the log book.

Data retrieved from NASA's ASRS site as of April 2012 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.