Engine-Separation during Take off in Kappstatt

[Dirk Kunze]

Beim Start in Kappstatt ging das Triebwerk einer B 737 verloren. Nähere Beschreibungen zum Umstand in diesen Foreneintrag. Allerdings war mir bislang nicht bekannt, dass die B 732 oder auch die NG Treibstoff ablassen können.

Trotzdem ist so eine engine separation heavy stuff und mich würde der entsprechende Untersuchungsbericht, insbesondere aber die statements der Piloten interessieren.

Prepare for the unexpected!

[Holger Illgen]

die 732 hat kein fuel jettison, steht glaub auch schon alles dazu im verlinkten Thread

Fotos

[Edgar Lindner]

Servus,

ist schon öfter vorgekommen, wie ich einem anderen Forum entnehmen konnte. Ich füge den Text einfach mal hier ein.

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Judging from earlier cases, readers should be skeptical about any ThReverser interaction before this latest ENGINE SEPARATION. See history of B737-200 cases.

Cone pins were used on B737-100s and -200s, and B727s (fuse pins employed on B747, B767, B757, and B737-300/400/500s).

NTSB sought hardware changes. A safety cable system had previously been used to hold engine after failure of primary structure -- then secondary support structure designed and installed (which also fractured in the DAL case).

[See also B707 and B747 cases where #3 Eng separates and then spears the #4 Eng.]

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Delta B737-200 7Jan92 DFW. Engine separation on takeoff. After T/O at 200' breakaway safety bolts called "Cone Pins" sheared for right engine. Engine bounced on grass on right side of runway.
http://www.ntsb.gov/ntsb/brief.asp?e...11X13985&key=1
... FTW92IA055 ....
... DELTA AIR LINES ...
... Tuesday, January 07, 1992 in DFW ...
... BOEING 737-232 ... N322DL ...

THE RIGHT ENGINE SEPARATED ... CLIMBING THROUGH 200 FEET AFTER TAKEOFF. ... UNEVENTFUL LANDING ...

ENGINE SEPARATION WAS THE RESULT OF THE FAILURE OF THE AFT CONE BOLT AND THE ENGINE SECONDARY SUPPORT ASSEMBLY. THE AFT CONE BOLT FAILED AS RESULT OF A PREEXISTING FATIGUE CRACK, WHILE THE ENGINE SECONDARY SUPPORT ASSEMBLY FAILED AS RESULT OF THE DYNAMIC LOADS THAT EXCEEDED THE DESIGNED CAPACITY OF THE MOUNTING BOLTS.

THE TWO FORWARD CONE BOLTS FAILED IN OVERLOAD AS THE ENGINE SWUNG FORWARD DURING THE SEPARATION SEQUENCE.

METALLURGICAL TESTING REVEALED THAT THE FATIGUE OF THE AFT CONE BOLT WAS A RESULT OF LUBRICANT INADVERTENTLY INTRODUCED INTO THE CONICAL SURFACE OF THE CONE BOLT.

...Board determines the probable cause ...
THE FAILURE OF THE AFT CONE BOLT AS RESULT OF PREEXISTING FATIGUE CRACKING DUE TO IMPROPER MAINTENANCE, AND THE FAILURE OF THE SECONDARY SUPPORT STRUCTURE AS A RESULT OF LOADS THAT EXCEEDED THE CAPACITY OF THE ATTACHING HARDWARE AND THE CRUSHABLE HONEYCOMB CORE.

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Piedmont Airlines B737-200, 20Jan89, right engine separated from aircraft after T/O at Chicago. Newly designed secondary support structure had not yet been installed.
http://www.ntsb.gov/ntsb/brief.asp?e...13X27558&key=1
... CHI89MA046 ....
... PIEDMONT AIRLINES
... Friday, January 20, 1989 in CHICAGO, IL ...
... BOEING 737-201 ... N242US ...

AN IN-FLIGHT TEARAWAY OF THE RIGHT ENGINE (FROM THE RIGHT WING) OCCURRED AS THE AIRPLANE LIFTED OFF FROM THE RUNWAY. ... CONTINUED THE TAKEOFF ... RETURNED ...

AN EXAM OF ITS WING & SEPARATED ENGINE REVEALED THE AFT CONE (ENG MOUNTING) BOLT HAD FAILED FROM FATIGUE, THEN THE TWO FORWARD CONE BOLTS FAILED FROM DUCTILE OVERSTRESS.

A RAISED MECHANICAL DEFORMATIVE WAS FOUND ON THE CONICAL SURFACE OF THE AFT BOLT. THE DEFORMITY WAS INDICATIVE OF DAMAGE PRODUCED PRIOR TO OR DURING ASSEMBLY OF THE CONE BOLT IN THE ISOLATION MOUNT. A MATCHING CAVITY WAS NOTED ON THE ISOLATION MOUNT. THERE WAS EVIDENCE THAT THE MECHANICAL IRREGULARITY RESULTED IN A NONUNIFORM FIT WHICH ALLOWED THE TORQUED FITTING TO LOOSEN DURING CYCLIC LOADING.

AD 88-01-07 REQUIRED THAT ULTRASONIC INSPECTION OF THE CONE BOLTS BE PERFORMED AT INTERVALS NOT TO EXCEED 600 CYCLES. AN ULTRASONIC INSPECTION OF THE BOLTS HAD BEEN ACCOMPLISHED ABOUT 330 CYCLES BEFORE THE ENGINE SEPARATED.

... Board determines the probable cause ...
PREVIOUS DAMAGE TO THE AFT CONE (ENGINE MOUNTING) BOLT, WHICH RESULTED IN MISMATCHED SURFACES BETWEEN THE BOLT AND ISOLATION MOUNT, LOSS OF TORQUE DURING CYCLIC LOADING OF THE MOUNTING BOLT, AND SUBSEQUENT FATIGUE FAILURE OF THE BOLT.

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US Air B737-200 PHL 5Dec87 #2 engine separated shortly after takeoff. Cracks caused by metal fatigue in one of three bolts; after rear bolt failed the two forward bolts and support cable failed in overload. http://www.ntsb.gov/ntsb/brief.asp?e...13X32769&key=1
... NYC88FA050 ....
... USAIR
... Saturday, December 05, 1987 ... DEPTFORD, NJ ...
... BOEING 737-2B7 ... N319AU ...

DRG TKOF, AS USAIR FLT 224 WAS CLBG THRU 4000', THE ACFT YAWED/ROLLED RGT. SIMULTANEOUSLY, THE CREW NOTICED THE #2 THROTTLE SLAM/LOCK TO THE IDLE PSN & A CONTINUOUS AIRFRAME BUFFET BEGAN.

SOON THEREAFTER, THE #2 ENG SEPD FM THE ACFT & THE BUFFET STOPPED.

THE ENG IMPACTED IN AN OPEN FLD, 6 MI FM THE ARPT.

JUST BFR IT SEPD, A PAX SAW THE AFT END OF THE #2 ENG MOMENTARILY DROOP ABOUT 30 DEG.

AFTER ENG SEPN, THE 'B' HYD SYS LOST PRES & THE TE FLAPS WOULD ONLY EXTD 10 DEG.

THE ACFT WAS LNDD SAFELY AFTER AN EMERG GEAR EXTN & DIFFERENTIAL BRAKING WAS USED FOR STEERING.

AN EXAM REVEALED THE AFT MOUNT CONE BOLT FOR THE #2 ENG HAD FAILED FM FATIGUE THRU THE THREAD RELIEF UNDERCUT RADIUS. FATIGUE CRACKS HAD INITIATED ON DIAMETRICALLY OPPOSITE SIDES OF THE RADIUS. SUBSEQUENTLY, THE FWD MOUNT CONE BOLTS & SECONDARY SUPPORT CABLE FAILED FROM OVERLOAD.

... Board determines the probable cause ...
ENGINE INSTALLATION, MOUNTING BOLT ..FATIGUE

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"Southwest 223" / 3Jan86 B737-2H4, after T/O from Love Field (Dallas), Rt Engine rear mount Cone Bolt sheared, mount failed and restraining cable broke; leaving the engine attached by only the two fwd mount bolts; returned safely. [AWST 124:31 Ja 13'86, photo.]

http://www.ntsb.gov/ntsb/brief.asp?e...10X00187&key=1
... FTW86MA030
... SOUTHWEST ...
... January 03, 1986 in DALLAS, TX
... BOEING 737-2H4 ... N86SW ...

THIS INCIDENT OCCURRED WHEN THE NO. 2 ENGINE EXPERIENCED AN AFT ENGINE MOUNT CONE BOLT FAILURE AND THE SUBSEQUENT FAILURE OF THE SECONDARY SUPPORT LINK (STAINLESS STEEL CABLE).

THE FAILURE OF BOTH AFT ENGINE SUPPORT ASSEMBLIES DURING THE TAKEOFF ROLL ALLOWED THE AFT SECTION OF THE ENG TO HANG DOWN TO WITHIN 4' [sic, transcription err] OF THE GROUND. AS A RESULT, THE NO.2 THRUST REVERSER ACTUATOR ASSEMBLY DRUG THE RUNWAY ON ROTATION.
... RETURNED ... LANDED...

METALLURGICAL EXAMINATION OF THE CONE BOLT REVEALED THAT IT FAILED AS A RESULT OF FATIGUE, MOST PROBABLY DUE TO IMPROPER INSTALLATION OF THE BOLT, SPECIFICALLY, THAT IT WAS UNDER TORQUED WHEN THE OPERATOR RE-INSTALLED THE ENG.

THE SAFETY CABLE FAILED AS A RESULT OF OVERSTRESS, PROBABLY INDUCED WHEN THE ACFT ENCOUNTERED A ROUGH STRETCH OF RUNWAY DURING THE TAKEOFF ROLL.

... Board determines the probable cause ...
ENGINE INSTALLATION, SUSPENSION MOUNTS .. FAILURE, PARTIAL
... FATIGUE ... SEPARATION ... OVERLOAD ... UNDERTORQUED
MAINTENANCE, INSTALLATION .. IMPROPER ...

Contributing Factors ... RUNWAY / LANDING AREA CONDITION ... ROUGH /UNEVEN

[Michael Koppenhöfer]

Wie war das? --- "BOEING" = Broken Off Engines In Numerous Gardens...

Cheers, Michael

[Andreas Boehme]

Zitat von Michael Koppenhöfer

Wie war das? --- "BOEING" = Broken Off Engines In Numerous Gardens...

Cheers, Michael

Wenn du das schreibst hast du bestimmt noch ein paar dokumentierte Beispiele auf Lager oder? Falls nicht finde ich das etwas unangebracht.

[Ben Becker]

Zitat von Andreas Boehme

Wenn du das schreibst hast du bestimmt noch ein paar dokumentierte Beispiele auf Lager oder? Falls nicht finde ich das etwas unangebracht.

Naja da gab's schon noch andere Fälle, wie den der El Al Cargo in Amsterdam. Daher stammt auch der BOEING-Spruch, wenn ich mich recht entsinne..

[Edgar Lindner]

Servus,

im Oktober 2004 hat eine 747 nach dem Start in Chicago ein Triebwerk verloren. Das Triebwerk fiel in den Lake Michigan.

http://www.airdisaster.com/forums/sh...ad.php?t=81108

Hier noch ein paar Beispiele (alles Frachter):

On Mar. 31, 1993, the No. 2 engine separated from a Japan Airlines Boeing 747-121 during climbout from Anchorage International Airport. Investigators determined the failure occurred when the engine pylon's ultimate lateral load capability was exceeded during the 747's encounter with severe or possibly extreme turbulence. The three crewmembers survived; the aircraft, manufactured in 1970, was substantially damaged. It had accumulated 83,906 hr. and its engines, 18,387 cycles.

On Dec. 29, 1991, the No. 3 engine separated from a China Airlines Boeing 747-2R7F during a high-speed climbout from Taiwan's Chiang Kai-Shek International Airport. The Pratt & Whitney JT9D-7R4G2 struck the No. 4 engine, which also detached from the 1980-manufactured aircraft. All five crew died in the subsequent crash. The 747 had accumulated 45,868 hr., and 9,094 engine cycles at the time of the accident.

On Oct. 4, 1992, the No. 3 Pratt & Whitney JT9D-7J engine and pylon separated from an El Al Israel Boeing 747-258F during climbout from Amsterdam Schipol Airport. As was the case with the China Airlines crash (above), the engine struck the No. 4 powerplant, detaching it from the 747. All four on board were killed when the aircraft crashed into an apartment building. The 1979-built 747 had 45,746 airframe hr. and its engines, 10,107 cycles.

U.S. Federal Aviation Aministration safety actions include a June 13, 2001, Airworthiness Directive (AD) requiring inspection and replacement of certain bolts in underwing fittings on Boeing 747-100, -200, -300 and SP series aircraft. According to the FAA, the action was necessary to prevent loss of the underwing fitting load path, which could result in separation of the engine.

In addition, on July 19 2004, the FAA issued an AD on the Boeing 747-100/B; 100B SUD; and -200B/C/F, -300, SR and SP aircraft equipped with Pratt & Whitney JT9D-3,-7-7Q and -7R4G2-series engines. The AD required drilling witness holes through the cowl skin at the cowl latch locations on the left side of the cowl panel assembly of each engine. The action is necessary to prevent the latch from disconnecting, which could result in separation of a cowl panel from the aircraft.

Gruß