In-flight fire. Air carrier crew has an in-flight fire indication due to improper maintenance work.

Attributes
ACN	299128
Time
Date	199503
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : sfo
State Reference	CA
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	other personnel other
Qualification	other other : other
ASRS Report	299128
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	other flight crewa
Resolutory Action	flight crew : declared emergency none taken : detected after the fact
Consequence	faa : investigated Other Other
Supplementary
Primary Problem	Aircraft

Narrative:

On mar/tue/95, an airline flight departing from sfo had a fire warning on the #1 engine shortly after takeoff requiring an engine shutdown. The aircraft returned to sfo at which time an air leak was discovered at the thrust reverser blocker valve location. This leak heated the fire loop which is within approximately 4-6 inches of this area causing the fire indication. The blocker valve had been replaced per our airline's operational and maintenance manual written documentation. This paperwork did not contain a leak check requirement, only an operational check per our airline's jet handbook section which checks reverser operation with engine running. The engineering department for this aspect of engine maintenance was contacted and will be incorporating a leak check into the aforementioned paperwork, as well as evaluating a preload problem at the same area. This condition has been noted with some installations where a gap of up to 1 inch will exist between the mating flanges of the blocker valve and the pneumatic ducting with one of the connecting 'V' clamps removed.

Original NASA ASRS Text

Title: INFLT FIRE. ACR CREW HAS AN INFLT FIRE INDICATION DUE TO IMPROPER MAINT WORK.

Narrative: ON MAR/TUE/95, AN AIRLINE FLT DEPARTING FROM SFO HAD A FIRE WARNING ON THE #1 ENG SHORTLY AFTER TKOF REQUIRING AN ENG SHUTDOWN. THE ACFT RETURNED TO SFO AT WHICH TIME AN AIR LEAK WAS DISCOVERED AT THE THRUST REVERSER BLOCKER VALVE LOCATION. THIS LEAK HEATED THE FIRE LOOP WHICH IS WITHIN APPROX 4-6 INCHES OF THIS AREA CAUSING THE FIRE INDICATION. THE BLOCKER VALVE HAD BEEN REPLACED PER OUR AIRLINE'S OPERATIONAL AND MAINT MANUAL WRITTEN DOCUMENTATION. THIS PAPERWORK DID NOT CONTAIN A LEAK CHK REQUIREMENT, ONLY AN OPERATIONAL CHK PER OUR AIRLINE'S JET HANDBOOK SECTION WHICH CHKS REVERSER OP WITH ENG RUNNING. THE ENGINEERING DEPT FOR THIS ASPECT OF ENG MAINT WAS CONTACTED AND WILL BE INCORPORATING A LEAK CHK INTO THE AFOREMENTIONED PAPERWORK, AS WELL AS EVALUATING A PRELOAD PROB AT THE SAME AREA. THIS CONDITION HAS BEEN NOTED WITH SOME INSTALLATIONS WHERE A GAP OF UP TO 1 INCH WILL EXIST BTWN THE MATING FLANGES OF THE BLOCKER VALVE AND THE PNEUMATIC DUCTING WITH ONE OF THE CONNECTING 'V' CLAMPS REMOVED.

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.