Return land by B-737 with APU fire warning lit.

Attributes
ACN	274743
Time
Date	199406
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : msp
State Reference	MN
Altitude	msl bound lower : 3000 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : msp tower : msp tracon : stl
Operator	common carrier : air carrier
Make Model Name	B737-200
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude landing other other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : cfi
Experience	flight time last 90 days : 180 flight time total : 2150 flight time type : 175
ASRS Report	274743
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : declared emergency other
Consequence	Other
Supplementary
Primary Problem	Aircraft

Narrative:

After a normal takeoff from runway 11L and climbing out of 3000 ft MSL, the APU fire warning bell sounded and associated lights illuminated in the cockpit. As the PNF the captain was performing the after takeoff checklist and shut down the APU as the fire warning indication started. The PNF accomplished immediate action steps by pulling the APU fire handle and rotating the handle to send extinguishing agent to the APU. The fire light in the APU handle remained 'on,' so the PNF asked ATC for immediate vectors back to msp. The PF, first officer, leveled off at 4000 ft MSL and followed radar vector instructions to land back at msp runway 22. PNF contacted flight attendants sitting aft cabin and determined no smoke or fumes entering cabin from tail section, so captain and first officer decided not to prepare the cabin in time available before landing, but did call for emergency equipment to meet aircraft on landing rollout at end of runway 22 at msp. Tower could not see any signs of fire/smoke from APU tail section and the fire chief made a complete visual inspection of the aircraft walking around the tail of the aircraft. Captain again spoke to flight attendants to determine no smoke entering the cabin, yet APU fire handle remained on. No actual fire discovered, so captain and first officer decided not to evacuate/evacuation the passenger and taxied back to a gate for normal passenger deplaning (ie, jetway). Total time airborne (in-flight) was 8 mins. PA announcements were made 3 times to passenger. First PA announcement was made in-flight on modified downwind to runway 22 at 3000 ft, passenger were told we had a mechanical problem and would land back at msp. The captain's biggest fear was a passenger initiated evacuate/evacuation. On landing rollout, passenger were informed of our actual emergency indications and actions with no actual fire discovered. The final announcement explained our decision to taxi back to the gate to offload passenger. Crew performance was high with first officer doing all the flying (maintaining aircraft control). Captain making all radio calls, executing immediate actions, referring to checklist, talking to flight attendants, and communication between captain/first officer was open about analyzing situation, keeping passenger informed, and deplaning passenger normally.

Original NASA ASRS Text

Title: RETURN LAND BY B-737 WITH APU FIRE WARNING LIT.

Narrative: AFTER A NORMAL TKOF FROM RWY 11L AND CLBING OUT OF 3000 FT MSL, THE APU FIRE WARNING BELL SOUNDED AND ASSOCIATED LIGHTS ILLUMINATED IN THE COCKPIT. AS THE PNF THE CAPT WAS PERFORMING THE AFTER TKOF CHKLIST AND SHUT DOWN THE APU AS THE FIRE WARNING INDICATION STARTED. THE PNF ACCOMPLISHED IMMEDIATE ACTION STEPS BY PULLING THE APU FIRE HANDLE AND ROTATING THE HANDLE TO SEND EXTINGUISHING AGENT TO THE APU. THE FIRE LIGHT IN THE APU HANDLE REMAINED 'ON,' SO THE PNF ASKED ATC FOR IMMEDIATE VECTORS BACK TO MSP. THE PF, FO, LEVELED OFF AT 4000 FT MSL AND FOLLOWED RADAR VECTOR INSTRUCTIONS TO LAND BACK AT MSP RWY 22. PNF CONTACTED FLT ATTENDANTS SITTING AFT CABIN AND DETERMINED NO SMOKE OR FUMES ENTERING CABIN FROM TAIL SECTION, SO CAPT AND FO DECIDED NOT TO PREPARE THE CABIN IN TIME AVAILABLE BEFORE LNDG, BUT DID CALL FOR EMER EQUIP TO MEET ACFT ON LNDG ROLLOUT AT END OF RWY 22 AT MSP. TWR COULD NOT SEE ANY SIGNS OF FIRE/SMOKE FROM APU TAIL SECTION AND THE FIRE CHIEF MADE A COMPLETE VISUAL INSPECTION OF THE ACFT WALKING AROUND THE TAIL OF THE ACFT. CAPT AGAIN SPOKE TO FLT ATTENDANTS TO DETERMINE NO SMOKE ENTERING THE CABIN, YET APU FIRE HANDLE REMAINED ON. NO ACTUAL FIRE DISCOVERED, SO CAPT AND FO DECIDED NOT TO EVAC THE PAX AND TAXIED BACK TO A GATE FOR NORMAL PAX DEPLANING (IE, JETWAY). TOTAL TIME AIRBORNE (INFLT) WAS 8 MINS. PA ANNOUNCEMENTS WERE MADE 3 TIMES TO PAX. FIRST PA ANNOUNCEMENT WAS MADE INFLT ON MODIFIED DOWNWIND TO RWY 22 AT 3000 FT, PAX WERE TOLD WE HAD A MECHANICAL PROB AND WOULD LAND BACK AT MSP. THE CAPT'S BIGGEST FEAR WAS A PAX INITIATED EVAC. ON LNDG ROLLOUT, PAX WERE INFORMED OF OUR ACTUAL EMER INDICATIONS AND ACTIONS WITH NO ACTUAL FIRE DISCOVERED. THE FINAL ANNOUNCEMENT EXPLAINED OUR DECISION TO TAXI BACK TO THE GATE TO OFFLOAD PAX. CREW PERFORMANCE WAS HIGH WITH FO DOING ALL THE FLYING (MAINTAINING ACFT CTL). CAPT MAKING ALL RADIO CALLS, EXECUTING IMMEDIATE ACTIONS, REFERRING TO CHKLIST, TALKING TO FLT ATTENDANTS, AND COM BTWN CAPT/FO WAS OPEN ABOUT ANALYZING SIT, KEEPING PAX INFORMED, AND DEPLANING PAX NORMALLY.

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.