|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||0601 To 1200|
|Locale Reference||airport : zzzz.airport|
|Operator||common carrier : air carrier|
|Make Model Name||B767-300 and 300 ER|
|Operating Under FAR Part||Part 121|
|Flight Phase||cruise : level|
descent : approach
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Anomaly||aircraft equipment problem : less severe|
non adherence : far
non adherence : published procedure
non adherence : company policies
|Independent Detector||aircraft equipment other aircraft equipment : eng vibration/radio alt authothrottle|
|Resolutory Action||none taken : anomaly accepted|
Flight Crew Human Performance
Out of ZZZ1 experienced some kind of electrical glitch that started with a warning signal emanating from beneath the cockpit ultimately shutting down the APU leaving us in the dark. After returning to the gate a review of events with maintenance generated this explanation. According to our maintenance supervisor the B767-300's have some slight modifications. Apparently with wind up the APU tailpipe; it begins to shut down causing the audible warning signal heard not only on the flight deck but as far back as the first class passenger section. Warning signal is an alert/precursor to losing cooling air over the IRU's as the flow inhibitor is triggered in the APU shutdown process. Then the APU finally quit leaving us all in the dark. Noting the winds were only around 5 to 8 KTS. Interesting. Started engines at the gate signed off logbook and departed normally. Airborne on climb out noted right engine fan vibration around 1.9 to 2.3 small but detectable vibration in the floor boards; but acceptable. During intermediate leveloff and climbs from departure to approximately abc noted right engine fan vibration getting incrementally worse with noted higher egt and vibration throughout the aircraft. Satcom teleconference with dispatch revealed an aircraft history of degradation in status of the right engine. Real time engine monitor and event status record confirmed mounting degradation of the right engine fan vibration. Our conclusion to slow the aircraft reducing power kept the right engine fan vibration within acceptable limits while continuing with the flight. WX was going down at our destination and our first alternate required a climb and cruise over hazardous mountainous terrain. We discussed our status and options and elected to use our second alternate which kept us predominately away from the mountains so as to preserve the right engine should it continue to degrade. Upon arrival our destination WX was up and down as we approached. To avoid any unnecessary higher thrust settings I declared with ATC a precaution status of our flight requested no holding and notification of destination arf equipment simply of our status. Upon our arrival a CAT 3 approach and landing was required due to reported field conditions. I understand the brief one fly one approach procedures we fly as professionals at our company. However; as we approached our destination on final approach we began to visually acquire the familiar and required airport landing environment required for making a normal landing. At 300 ft the autothrottles uncommanded disconnected and the radio altimeter system failed. At this point with our current status as outlined above I exercised my captain's authority/authorized; disconnected the autoplts took over manually and made the landing.
Original NASA ASRS Text
Title: A B767-300 WITH AN ENGINE ANOMALY WAS FLOWN CONSERVATIVELY TO A FOREIGN DESTINATION. DURING A CAT 3 APCH THE CAPT LANDED VMC FOLLOWING RADIO ALT AND AUTOTHROTTLE ANOMALIES.
Narrative: OUT OF ZZZ1 EXPERIENCED SOME KIND OF ELECTRICAL GLITCH THAT STARTED WITH A WARNING SIGNAL EMANATING FROM BENEATH THE COCKPIT ULTIMATELY SHUTTING DOWN THE APU LEAVING US IN THE DARK. AFTER RETURNING TO THE GATE A REVIEW OF EVENTS WITH MAINT GENERATED THIS EXPLANATION. ACCORDING TO OUR MAINT SUPVR THE B767-300'S HAVE SOME SLIGHT MODIFICATIONS. APPARENTLY WITH WIND UP THE APU TAILPIPE; IT BEGINS TO SHUT DOWN CAUSING THE AUDIBLE WARNING SIGNAL HEARD NOT ONLY ON THE FLT DECK BUT AS FAR BACK AS THE FIRST CLASS PAX SECTION. WARNING SIGNAL IS AN ALERT/PRECURSOR TO LOSING COOLING AIR OVER THE IRU'S AS THE FLOW INHIBITOR IS TRIGGERED IN THE APU SHUTDOWN PROCESS. THEN THE APU FINALLY QUIT LEAVING US ALL IN THE DARK. NOTING THE WINDS WERE ONLY AROUND 5 TO 8 KTS. INTERESTING. STARTED ENGS AT THE GATE SIGNED OFF LOGBOOK AND DEPARTED NORMALLY. AIRBORNE ON CLBOUT NOTED RIGHT ENG FAN VIBRATION AROUND 1.9 TO 2.3 SMALL BUT DETECTABLE VIBRATION IN THE FLOOR BOARDS; BUT ACCEPTABLE. DURING INTERMEDIATE LEVELOFF AND CLBS FROM DEP TO APPROX ABC NOTED R ENG FAN VIBRATION GETTING INCREMENTALLY WORSE WITH NOTED HIGHER EGT AND VIBRATION THROUGHOUT THE ACFT. SATCOM TELECONFERENCE WITH DISPATCH REVEALED AN ACFT HISTORY OF DEGRADATION IN STATUS OF THE R ENG. REAL TIME ENG MONITOR AND EVENT STATUS RECORD CONFIRMED MOUNTING DEGRADATION OF THE R ENG FAN VIBRATION. OUR CONCLUSION TO SLOW THE ACFT REDUCING PWR KEPT THE RIGHT ENG FAN VIBRATION WITHIN ACCEPTABLE LIMITS WHILE CONTINUING WITH THE FLT. WX WAS GOING DOWN AT OUR DEST AND OUR FIRST ALTERNATE REQUIRED A CLB AND CRUISE OVER HAZARDOUS MOUNTAINOUS TERRAIN. WE DISCUSSED OUR STATUS AND OPTIONS AND ELECTED TO USE OUR SECOND ALTERNATE WHICH KEPT US PREDOMINATELY AWAY FROM THE MOUNTAINS SO AS TO PRESERVE THE R ENG SHOULD IT CONTINUE TO DEGRADE. UPON ARR OUR DEST WX WAS UP AND DOWN AS WE APCHED. TO AVOID ANY UNNECESSARY HIGHER THRUST SETTINGS I DECLARED WITH ATC A PRECAUTION STATUS OF OUR FLT REQUESTED NO HOLDING AND NOTIFICATION OF DEST ARF EQUIP SIMPLY OF OUR STATUS. UPON OUR ARR A CAT 3 APCH AND LNDG WAS REQUIRED DUE TO RPTED FIELD CONDITIONS. I UNDERSTAND THE BRIEF ONE FLY ONE APCH PROCS WE FLY AS PROFESSIONALS AT OUR COMPANY. HOWEVER; AS WE APCHED OUR DEST ON FINAL APCH WE BEGAN TO VISUALLY ACQUIRE THE FAMILIAR AND REQUIRED ARPT LNDG ENVIRONMENT REQUIRED FOR MAKING A NORMAL LNDG. AT 300 FT THE AUTOTHROTTLES UNCOMMANDED DISCONNECTED AND THE RADIO ALTIMETER SYS FAILED. AT THIS POINT WITH OUR CURRENT STATUS AS OUTLINED ABOVE I EXERCISED MY CAPT'S AUTH; DISCONNECTED THE AUTOPLTS TOOK OVER MANUALLY AND MADE THE LNDG.
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.