Abantu abayishumi nanye bashonile izolo ebusuku e-Oahu, ngenkathi indiza ye-Beech 65-A90 iphahlazeka ngemuva nje kokusuka e-Dillingham Airfield on North Shore yase-Oahu, eHawaii. Kuthathwa njengenhlekelele yendiza yezentengiselwano ebulala kakhulu e-US State of Hawaii kule minyaka engamashumi amabili edlule.
Indiza ngokusobala inomlando wezinkinga. Ngo-2016 iNational Transportation Safety Board (NTSB) yathumela umbiko olandelayo mayelana nesigameko lapho le ndiza isetshenziswa eCalifornia.
Ngomhla zingama-23 kuJulayi, 2016, cishe ngo-1900 isikhathi sasemini sase-Pacific, i-Beech 65-A90, N256TA, yathola umonakalo omkhulu kulandela ukulahlekelwa ukulawula ngenkathi ikhuphuka eduze kwase-Byron Airport (C83) Byron, California. Umshayeli wendiza yezohwebo kanye nabagibeli abangu-14 abalimalanga. Indiza yayibhaliswe ku-N80896 LLC, futhi isetshenziswa yi-Bay Area Skydiving ngaphansi kwezinhlinzeko ze-14 Code of Federal Regulations Ingxenye 91. Izimo ezibukwayo zezulu zazikhona futhi alukho uhlelo lwendiza olufakiwe lwendiza yokutshuza esibhakabhakeni. Indiza yasendaweni yasuka i-C83 cishe ngo-1851.
Ngokusho komshayeli wendiza, njengoba indiza isondela endaweni yokugxuma kanye nokuphakama okuhleliwe, cishe i-12,500 ft, okusho izinga lolwandle, waqala ukujikela kwesokunxele ukuze ahlele indawo yokudonsa. Uthe isivinini sendiza sahamba kancane wabe esethi “kuthe kusenjalo indiza yama kungazelelwe, yagingqika kwesokunxele, yaqala ukuzungeza ikhala yehle.” Uthe indiza "yenza imiphongolo ebheke phansi embalwa." Omunye wabagxumayo, ohlezi esihlalweni somshayeli wendiza, wezwa “umsindo omkhulu” phakathi nochungechunge lokululama futhi wathi “umshayeli wendiza akazange ayibambezelele imisindo phakathi nokululama, okwabangela ukuba indiza ithuthuke kakhulu.” Uqhube wathi ngesikhathi elulama wezwa i-g-force esiswini sakhe. Umshayeli wendiza uthe ubuyisele indiza okwesikhashana esimweni esisezingeni lamaphiko imizuzwana embalwa futhi waqaphela ukuthi indiza ibicishe ibe ngu-90° esihlokweni ebesihleliwe, futhi ihamba kancane ngesivinini somoya.
Kamuva, umshayeli wendiza wathi kukhona “ukushaqeka” kwezilawuli futhi “ngaso leso sikhathi indiza yaphuka kanzima kwesokunxele,” yama okwesibili, yaqala ukuzungeza ibheke phansi. Umshayeli wendiza utshele abatshuzi besibhakabhaka ukuthi bagxume baphume endizeni. Ama-parachutists athobela, futhi wonke aphuma ngempumelelo endizeni phakathi nalo mcimbi wesibili wokuzungeza. Umshayeli wabe eseqala izinqubo zokubuyisela i-spin ngaphandle komphumela obonakalayo ngokuzungezisa okungaba ngu-9 futhi wathi izinga lokugoqa lalishesha kakhulu kunomcimbi wokuqala wokuzungeza. Wabe esedonsa zombili izinsimbi zokulawula uphephela endaweni yophaphe futhi wakwazi ukuphuma ku-spin. Wabuyisela indiza esimweni sengqondo sephiko neleveli, kodwa ngokushesha ngemva kwalokho, indiza “yaphuka kwesokunxele” futhi yama okwesithathu. Umshayeli waphinde wabuyisela indiza ngokwehlisa izinga lendiza futhi andise isivinini.
Umshayeli wajikela emuva ebheke esikhumulweni sezindiza futhi njengoba indiza yayiphethe ngendlela engavamile, walungisa ikheshi ukuze lifinyelele endaweni yalo egcwele ikhala ukuze limsize abambe indiza eqondile futhi ileveli. Uthe kusetshenziswe ukusetha okugcwele kwekhala kuze kusetshenziswe endleleni. Ngaphezu kwalokho, umshayeli undize amafindo angu-15 ngokushesha kunalokho okudingekayo, ukuze anxephezele udaba lokulawula lokwehla okuphawulekayo ekusebenzeni kwekheshi.
Umshayeli wendiza uchaze ukuthi le ndawo ifike ishone phansi uma iqhathaniswa nokuhlala okuvamile. Ngemva kokufika ku-C83, ufakazi wabona ukuthi isizinzisi esivundlile sendiza esingakwesokudla, nekheshi elinamathiselwe, sasingekho. Izingxenye zendiza ezihlukanisiwe zabe sezitholakala endaweni engamakhilomitha ambalwa eningizimu yesikhumulo sezindiza.
Umshayeli wendiza ubike ukuthi akukho okungahambi kahle ngendiza ezindizeni zangaphambilini ngalolo suku, noma ngesikhathi sokuhlolwa kwakhe ngaphambi kokundiza kwendiza yengozi. Uveze ukuthi izulu belicwebile kanti bekukhona ne-light chop. Ngaphezu kwalokho, akazange abike izinkinga zenjini phakathi nendiza.
Ukuhlolwa kwendiza ngemuva kwengozi kwembula ukuthi izikhumba zephiko ezingaphezulu nezangaphansi aziphawuleki. Izigingqiki zenjini kanye namaphoyinti okunamathiselwe okuzinzisa angakwesokunxele ahlolelwe ukucindezela, kodwa akukho okubonwayo. Azikho izimpawu ze-flutter ezibonwe ku-stabilizer evundlile kwesokunxele.
Isizinzisi esivundlile esingakwesokudla, esifakwe ikheshi, esasihlukene nendiza, sahlolwa. I-lifti engakwesokudla kanye nethebhu yokunquma ikheshi ihlale inamathele ezindaweni zazo zokunamathisela ngokulandelana kwazo. Ukuqhekeka kubonwe onqenqemeni oluyinhloko nolulandela ngemuva kwe-spars evundlile kusinzinzisi esivundlile kwesokudla. Kwakukhona ukushwabana endaweni yesikhumba. Ubakaki wokunamathiselwe oxhume isizinzisi esingakwesokudla esivundlile endizeni, nakwesinye isizinzisi esivundlile, babonise izindawo zokuphuka kwesokudla lapho kunamathiselwe khona isizinzisi esivundlile kwesokudla.
Izingxenye zesizinzisi esivundlile kwesokudla, ikheshi, kanye nabakaki abanamathiselwe kuthunyelwe ku-National Transportation Safety Board Materials Laboratory ukuze kuqhutshekwe nokuhlolwa. Ukuhlolwa kokubona okukhulisiwe kwezindawo zokuphuka kwembula izici ezihambisana nokuhlukaniswa kokucindezeleka ngokweqile. Akukho sibonakaliso sokukhathala noma ukugqwala okubonwayo. Ukuguquguquka namaphethini okuphuka kuma-spars okuzinzisa avundlile angakwesokudla ayebonisa ithiphu le-stabilizer eligobayo futhi i-spar engezansi nayo ibe nokudabuka phezulu kwamawebhu.
I-spin spin ye-flight manual yendiza ithi: “susa ikholomu yokulawula igcwale phambili ngokushesha, sebenzisa iphini eligcwele elibhekene nendawo lapho i-spin, bese unciphisa amandla kuzo zombili izinjini ukuze zingenzi lutho. Lezi zenzo ezintathu kufanele zenziwe eduze ngesikhathi esisodwa ngangokunokwenzeka, bese uqhubeke ubambe lesi sikhundla sokulawula kuze kube yilapho ukuzungezisa kuma bese unciphisa zonke izilawuli futhi ukhiphe ukudonsa okushelelayo. U-Ailerons kufanele angathathi hlangothi ngesikhathi sokululama. ”
Isisindo sendiza kanye nebhalansi kubalwe ngendiza yengozi. Isikhungo samandla adonsela phansi (CG) silinganiselwa ukuthi singamayunithi angu-6-7 ngemva komkhawulo. Ngenxa yokuthi isikhungo samandla adonsela phansi (cg) singaphezu komkhawulo, isisindo esiphelele esivumelekile asikwazanga ukunqunywa ngesikhathi sengozi. Ngokwe-FAA Pilot Handbook of Aeronautical Knowledge ithi, “njengoba i-CG inyakaza, kuba nesimo esingazinzi kangako, esinciphisa ikhono lendiza lokuziqonda kahle ngemva kokuzulazula noma ukuyaluza.”
