Narrative:

While cruising at FL330 and heading east nebound, roughly 10 mi south of cimarron, NM, a very loud bang and jolt was experienced in the aircraft and cockpit. The captain disconnected the autoplt and hand flew the aircraft straight and level while he and the first officer assessed the situation. The crew quickly saw that the right engine indications were rapidly unwinding and that the right engine had lost power. Hydraulic and flight controls appeared to be normal, and cabin pressure remained unaffected. There was no unusual difficulty in controling the aircraft although airspeed had begun to decay as a result of thrust loss. The right engine indications showed engine rotation, which could roughly be described as a low idle power setting, with corresponding egt and fuel flow. Oil pressure and quantity were normal, but oil temperature appeared somewhat high. There was no fire warning and no further vibration to suggest an unbalanced engine with compressor blade or turbine failure. The exact nature of our problem was difficult to determine, as it did not reflect the common characteristics of a classic engine failure, yet it was obvious that we had some sort of serious engine distress. The autothrottles were disconnected. There was no discernible response to retarding the right throttle, but because it appeared that the engine might be operating, and because he wished to avoid an unnecessary shutdown, the captain chose to slowly re-advance the power lever to determine if power could be restored. There was little to no engine response, and the crew agreed that there was probably damage to the engine that would warrant a shutdown. The captain called for the QRH, engine fire/severe damage/separation checklist, and a driftdown speed. As the first officer pulled the QRH out of the rack, there was a discussion concerning potential diversion airports. WX appeared to be more favorable off to the north towards denver. The crew worked through the first few steps of the QRH and shut the engine down using the fuel control lever and the fire handle. The captain held the checklist for a few moments to declare an emergency to ATC and ask for vectors towards denver. We asked for a lower altitude and were cleared to FL270 on a northerly heading. We consulted with ATC and checked our commercial manuals and found that a suitable airport was only 111 NM north of our initial position, and that it had a 10000 ft runway. The first officer checked ATIS and found the airport reporting good WX with scattered clouds at 11000 ft, 8 mi visibility, and east winds. The captain was reluctant to descend any further until the nearest suitable airport had been idented, and held FL270 for several mins. Once it became clear that ZZZ airport was the nearest suitable, ATC cleared the flight to 11000 ft, and we began our descent. At this point, the crew continued to work through applicable QRH procedures while dealing with numerous ATC calls, a call to the flight attendants to brief them on our situation, and making a PA to the passenger. This was, perhaps, the most difficult period in that managing the overall situation, which became very complex, given the numerous interruptions to any one task or focus. In addition, the QRH procedures did not entirely fit our circumstances, and it was necessary to modestly improvise to insure that the APU was started, and that the engine sync was turned off. The captain concluded that the landing would not require procedures be implemented in the cabin. He indicated to the flight attendants that it would not be necessary to brace the passenger for landing. Since the aircraft had been held at FL270 until determining that the airport was the most suitable, and the descent started relatively close in, the aircraft was somewhat high for the approach, and it became apparent that the aircraft needed to break off the approach while continuing to descend. The captain decided to break off the approach to the north, and to make a 360 degree turn to the left, which would again roll out on the final approach course. The intent of making the turn to the left was to enable the captain to visually acquire the runway more easily, as the aircraft rolled out on final. Shortly after reaching a northerly heading, the tower controller informed us of a tv antenna approximately 5 mi north at about 6300 ft MSL. At the time, our altwas just under 5900 ft. Because we could not locate the tower visually, we became concerned, and as we approached 3 mi from the tower, the captain abandoned the idea of the left 360 degree turn in favor of turning to the right, back across the airport to the south to re-enter a right downwind for runway 8. A normal single engine approach and landing was flown from the right downwind. Crash fire rescue equipment trucks followed the aircraft. They reported no visible damage and no fluid leaking. When the aircraft was stopped for this inspection, the first officer contacted occ and informed them of the diversion. At no time during flight was there an opportunity to contact occ and amend the dispatch release to reflect ZZZ as the new destination airport, and as such, the captain has exercised his emergency authority/authorized under the far's. I am seriously concerned about the FAA's position which requires air carrier's to adopt manufacturer's emergency procedures verbatim. Manufacturer's afm procedures tend to be 'switchology' or engineering responses to system malfunctions, as opposed to real life operational management tools. It has become difficult for operators to modify procedures to enhance their value and usefulness to the flight crew's in the real world. In addition, while the immediate return checklist does provide for APU start, it does not mention turning engine sync 'off' prior to landing gear extension. Even if we assume that the climb check has not been started, there are some occasions when the engine sync is turned on prior to actually calling for the climb check as part of turning on the automatic throttles. This makes it advantageous to add the engine sync 'off' item in the immediate return checklist as well. Supplemental information from acn 572141: I went to hangar to look at the removed right engine. The mechanic showed me that the #3 turbine rotor stage appeared to be the cause of the failure. The stator vanes were damaged, and the #4 turbine rotor stage was sheared off -- somewhere in pieces in northwest NM. Have there been a bad history with this rotor stage on JT8D engines?

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Original NASA ASRS Text

Title: MD-82 FLC EXPERIENCE R ENG MALFUNCTION AND COMMENTS ON USE OF MANUFACTURER CHECKLISTS DURING ABNORMAL PROCEDURES.

Narrative: WHILE CRUISING AT FL330 AND HEADING E NEBOUND, ROUGHLY 10 MI S OF CIMARRON, NM, A VERY LOUD BANG AND JOLT WAS EXPERIENCED IN THE ACFT AND COCKPIT. THE CAPT DISCONNECTED THE AUTOPLT AND HAND FLEW THE ACFT STRAIGHT AND LEVEL WHILE HE AND THE FO ASSESSED THE SIT. THE CREW QUICKLY SAW THAT THE R ENG INDICATIONS WERE RAPIDLY UNWINDING AND THAT THE R ENG HAD LOST PWR. HYD AND FLT CTLS APPEARED TO BE NORMAL, AND CABIN PRESSURE REMAINED UNAFFECTED. THERE WAS NO UNUSUAL DIFFICULTY IN CTLING THE ACFT ALTHOUGH AIRSPD HAD BEGUN TO DECAY AS A RESULT OF THRUST LOSS. THE R ENG INDICATIONS SHOWED ENG ROTATION, WHICH COULD ROUGHLY BE DESCRIBED AS A LOW IDLE PWR SETTING, WITH CORRESPONDING EGT AND FUEL FLOW. OIL PRESSURE AND QUANTITY WERE NORMAL, BUT OIL TEMP APPEARED SOMEWHAT HIGH. THERE WAS NO FIRE WARNING AND NO FURTHER VIBRATION TO SUGGEST AN UNBALANCED ENG WITH COMPRESSOR BLADE OR TURBINE FAILURE. THE EXACT NATURE OF OUR PROB WAS DIFFICULT TO DETERMINE, AS IT DID NOT REFLECT THE COMMON CHARACTERISTICS OF A CLASSIC ENG FAILURE, YET IT WAS OBVIOUS THAT WE HAD SOME SORT OF SERIOUS ENG DISTRESS. THE AUTOTHROTTLES WERE DISCONNECTED. THERE WAS NO DISCERNIBLE RESPONSE TO RETARDING THE R THROTTLE, BUT BECAUSE IT APPEARED THAT THE ENG MIGHT BE OPERATING, AND BECAUSE HE WISHED TO AVOID AN UNNECESSARY SHUTDOWN, THE CAPT CHOSE TO SLOWLY RE-ADVANCE THE PWR LEVER TO DETERMINE IF PWR COULD BE RESTORED. THERE WAS LITTLE TO NO ENG RESPONSE, AND THE CREW AGREED THAT THERE WAS PROBABLY DAMAGE TO THE ENG THAT WOULD WARRANT A SHUTDOWN. THE CAPT CALLED FOR THE QRH, ENG FIRE/SEVERE DAMAGE/SEPARATION CHKLIST, AND A DRIFTDOWN SPD. AS THE FO PULLED THE QRH OUT OF THE RACK, THERE WAS A DISCUSSION CONCERNING POTENTIAL DIVERSION ARPTS. WX APPEARED TO BE MORE FAVORABLE OFF TO THE N TOWARDS DENVER. THE CREW WORKED THROUGH THE FIRST FEW STEPS OF THE QRH AND SHUT THE ENG DOWN USING THE FUEL CTL LEVER AND THE FIRE HANDLE. THE CAPT HELD THE CHKLIST FOR A FEW MOMENTS TO DECLARE AN EMER TO ATC AND ASK FOR VECTORS TOWARDS DENVER. WE ASKED FOR A LOWER ALT AND WERE CLRED TO FL270 ON A NORTHERLY HDG. WE CONSULTED WITH ATC AND CHKED OUR COMMERCIAL MANUALS AND FOUND THAT A SUITABLE ARPT WAS ONLY 111 NM N OF OUR INITIAL POS, AND THAT IT HAD A 10000 FT RWY. THE FO CHKED ATIS AND FOUND THE ARPT RPTING GOOD WX WITH SCATTERED CLOUDS AT 11000 FT, 8 MI VISIBILITY, AND E WINDS. THE CAPT WAS RELUCTANT TO DSND ANY FURTHER UNTIL THE NEAREST SUITABLE ARPT HAD BEEN IDENTED, AND HELD FL270 FOR SEVERAL MINS. ONCE IT BECAME CLR THAT ZZZ ARPT WAS THE NEAREST SUITABLE, ATC CLRED THE FLT TO 11000 FT, AND WE BEGAN OUR DSCNT. AT THIS POINT, THE CREW CONTINUED TO WORK THROUGH APPLICABLE QRH PROCS WHILE DEALING WITH NUMEROUS ATC CALLS, A CALL TO THE FLT ATTENDANTS TO BRIEF THEM ON OUR SIT, AND MAKING A PA TO THE PAX. THIS WAS, PERHAPS, THE MOST DIFFICULT PERIOD IN THAT MANAGING THE OVERALL SIT, WHICH BECAME VERY COMPLEX, GIVEN THE NUMEROUS INTERRUPTIONS TO ANY ONE TASK OR FOCUS. IN ADDITION, THE QRH PROCS DID NOT ENTIRELY FIT OUR CIRCUMSTANCES, AND IT WAS NECESSARY TO MODESTLY IMPROVISE TO INSURE THAT THE APU WAS STARTED, AND THAT THE ENG SYNC WAS TURNED OFF. THE CAPT CONCLUDED THAT THE LNDG WOULD NOT REQUIRE PROCS BE IMPLEMENTED IN THE CABIN. HE INDICATED TO THE FLT ATTENDANTS THAT IT WOULD NOT BE NECESSARY TO BRACE THE PAX FOR LNDG. SINCE THE ACFT HAD BEEN HELD AT FL270 UNTIL DETERMINING THAT THE ARPT WAS THE MOST SUITABLE, AND THE DSCNT STARTED RELATIVELY CLOSE IN, THE ACFT WAS SOMEWHAT HIGH FOR THE APCH, AND IT BECAME APPARENT THAT THE ACFT NEEDED TO BREAK OFF THE APCH WHILE CONTINUING TO DSND. THE CAPT DECIDED TO BREAK OFF THE APCH TO THE N, AND TO MAKE A 360 DEG TURN TO THE L, WHICH WOULD AGAIN ROLL OUT ON THE FINAL APCH COURSE. THE INTENT OF MAKING THE TURN TO THE L WAS TO ENABLE THE CAPT TO VISUALLY ACQUIRE THE RWY MORE EASILY, AS THE ACFT ROLLED OUT ON FINAL. SHORTLY AFTER REACHING A NORTHERLY HDG, THE TWR CTLR INFORMED US OF A TV ANTENNA APPROX 5 MI N AT ABOUT 6300 FT MSL. AT THE TIME, OUR ALTWAS JUST UNDER 5900 FT. BECAUSE WE COULD NOT LOCATE THE TWR VISUALLY, WE BECAME CONCERNED, AND AS WE APCHED 3 MI FROM THE TWR, THE CAPT ABANDONED THE IDEA OF THE L 360 DEG TURN IN FAVOR OF TURNING TO THE R, BACK ACROSS THE ARPT TO THE S TO RE-ENTER A R DOWNWIND FOR RWY 8. A NORMAL SINGLE ENG APCH AND LNDG WAS FLOWN FROM THE R DOWNWIND. CFR TRUCKS FOLLOWED THE ACFT. THEY RPTED NO VISIBLE DAMAGE AND NO FLUID LEAKING. WHEN THE ACFT WAS STOPPED FOR THIS INSPECTION, THE FO CONTACTED OCC AND INFORMED THEM OF THE DIVERSION. AT NO TIME DURING FLT WAS THERE AN OPPORTUNITY TO CONTACT OCC AND AMEND THE DISPATCH RELEASE TO REFLECT ZZZ AS THE NEW DEST ARPT, AND AS SUCH, THE CAPT HAS EXERCISED HIS EMER AUTH UNDER THE FAR'S. I AM SERIOUSLY CONCERNED ABOUT THE FAA'S POS WHICH REQUIRES ACR'S TO ADOPT MANUFACTURER'S EMER PROCS VERBATIM. MANUFACTURER'S AFM PROCS TEND TO BE 'SWITCHOLOGY' OR ENGINEERING RESPONSES TO SYS MALFUNCTIONS, AS OPPOSED TO REAL LIFE OPERATIONAL MGMNT TOOLS. IT HAS BECOME DIFFICULT FOR OPERATORS TO MODIFY PROCS TO ENHANCE THEIR VALUE AND USEFULNESS TO THE FLT CREW'S IN THE REAL WORLD. IN ADDITION, WHILE THE IMMEDIATE RETURN CHKLIST DOES PROVIDE FOR APU START, IT DOES NOT MENTION TURNING ENG SYNC 'OFF' PRIOR TO LNDG GEAR EXTENSION. EVEN IF WE ASSUME THAT THE CLB CHK HAS NOT BEEN STARTED, THERE ARE SOME OCCASIONS WHEN THE ENG SYNC IS TURNED ON PRIOR TO ACTUALLY CALLING FOR THE CLB CHK AS PART OF TURNING ON THE AUTO THROTTLES. THIS MAKES IT ADVANTAGEOUS TO ADD THE ENG SYNC 'OFF' ITEM IN THE IMMEDIATE RETURN CHKLIST AS WELL. SUPPLEMENTAL INFO FROM ACN 572141: I WENT TO HANGAR TO LOOK AT THE REMOVED R ENG. THE MECH SHOWED ME THAT THE #3 TURBINE ROTOR STAGE APPEARED TO BE THE CAUSE OF THE FAILURE. THE STATOR VANES WERE DAMAGED, AND THE #4 TURBINE ROTOR STAGE WAS SHEARED OFF -- SOMEWHERE IN PIECES IN NW NM. HAVE THERE BEEN A BAD HISTORY WITH THIS ROTOR STAGE ON JT8D ENGS?

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.