Page:CAB Accident Report, Braniff Airways Flight 542.pdf/12

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The separation of the rlght wlng occurred between Wlng statlon No. 329 and wlng: statlon No. 3h6. The lower No. 3 plank lnboard of Wlng statlon No. 3ho showed a shear buckle pattern from Wlng statlon do. 329 to Wlng statlon No. 3h6. The upper surface panels were bent sllghtly upward 1n the area of the break and the broken ends of the stlffeners were pulled rearward. The rlght w1ng showed no ev1dence of havlng been exposed to heat, smoke, soot or flame lmplngement.

The propeller, englne gear case, alr lnlet houSlng, and the qulck englne change structure of the No. l powerplant separated as a unlt as a result of fallure of nacelle and/or QEC longerons at the QEC — nacelle flttlngs. The englne unit aft of the compressor front face remalned 1n the No. l nacelle and descended wlth the left wlng.

The fOrward attach pelnt of the No. l EEC upper outboard longeron showed heawjr compresslon loadlng prlor to fallure and further dlsclosed multlple dlrectlons of local bendlng 1n the several longeron members.

The forward attach area of the No. 1 QEE upper lnboard longeron showed a tenSlon fallure followed by recentact of the fracture faces durlng a would-be compreSSlon load.

The electrlcal connectors and thelr erlng at the No. l nacelle flrewall were falled ln.nmlt1ple dlrectlons of bendlng.

At the No. l nacelle flrewall, the fuel 11118 was bent up/lnboard and down/outboar: prlor to the ultlmate fallure whlch was up/outboard.

Indentatlons were found 1n the nacelle shroud whlch were made by'the antl- swlrl assembly clamp, partlcularly 1n the area of the clamp bolts. There were 1ndlcatlons here of not less than seven contacts of the bosses Wlth the nacelle. There were also multlple clamp marks around the shroud but less pronouncsd than those at the clamp spllt—llne.

All panels and structure of the No. 2 QEC and nacelle were accounted for and lncluded the landlng gear door and starter compressor sectlon. Thls entlre sectlon wlth the exceptlon of the outboard starter compressor houSlng showed evldence of havlng been subjected to flre and heat exposure. A conSlderable amount of molten alumlnum dep051ts was found throughout the nacelle area, however, none of the dep031ts showed ev1dence of haVlng been blown by an alrstream.

The No. 3 QEC and nacelle were both completely demollshed by ground lmpact. All examlned pleces of thls area revealed no eVldence of haVlng been exposed to flre or heat nor was there any ev1dence of smoke or soot depOSlts ln thls area.

The No. h nacelle barrel outboard panel was peeled dlrectly outboard and aft, and rlvets 1n the lower forward corner of the lnboard barrel Slde panel were sheared 1n a forward directlon. All flrewall flttlngs were bent outboard and cables notched the flrewall 1n an outboard dlrectlon. Only those portlons of the Structure whlch were carrled to the ground w1th the englne showed any lndlcatlons of exposure to flre or heat.

The forward fuselage sectlon.from the nose through apprOleately fuselage Statlon No. 570 was subjected to severe lmpact forces when 1t struck the ground ami