Rịba ama amaokwu a dị n'okpuru ma zaa ajụjụ ahụ mgbe e mesịrị n'otu asụsụ ahụ dị ka amaokwu ahụ:  Ịgafe: N'oge ndị e mesịrị n'usoro ule ụgbọelu ahụ, nnwale e mere iji hụ na nku ndị ahụ na-ama jijiji n'ọnọdụ ụfọdụ gosiri na ha na-ama jijiji. E doziri nsogbu a n'ụzọ ụfọdụ site n'ibelata nkwụsi ike nke akụkụ ụfọdụ nke nku ahụ. Otú ọ dị, a na-edozi nsogbu dị oke egwu na-agba ọsọ ọsọ ọsọ naanị site na itinye uranium na-emebi emebi dị ka ballast na engine nacelles nke mmalite 747s. Nke a mere ka ndị mmadụ na-echegbu onwe ha mgbe ụgbọelu ndị a dara, dịka ọmụmaatụ El Al Flight 1862 na Amsterdam na 1992 na 282 kilogram (622 lb) nke uranium na tailplane (horizontal stabilizer). Ihe isi ike gụnyere engine stalls mere site ngwa ngwa throttle mmegharị na distortion nke turbine casings mgbe a obere oge nke ọrụ. Nsogbu ndị a mere ka nnyefe nke ụgbọelu 747 were ọnwa ole na ole; ihe ruru ụgbọelu iri abụọ n'ụlọ ọrụ Everett nọ na-echere mgbe a ga-arụnye ha injin. A na-egbu oge mmemme ahụ mgbe otu n'ime ụgbọ elu nnwale ise ahụ merụrụ ahụ nke ukwuu n'oge a na-anwa ịbata na Renton Municipal Airport, saịtị nke ụlọ ọrụ Renton. Na December 13, 1969, a nọ na-ebupụ otu ụgbọelu e ji eme nnyocha ka e wepụ ngwá ọrụ e ji eme nnyocha na ya ma rụnye otu ụlọ n'ime ya mgbe onye na-anya ụgbọelu bụ́ Ralph C. Cokely gbapụrụ n'okporo ụzọ dị mkpirikpi nke ọdụ ụgbọelu ahụ. A dọkasịrị aka nri nke ụgbọelu 747 ahụ, a dọkasịrị ihe ndị e ji ebu ụgbọelu na-agbadata n'èzí ya, e mebisikwara ihe ndị e ji ebu ụgbọelu abụọ. Otú ọ dị, ihe isi ike ndị a egbochighị Boeing iwere ụgbọelu nnwale na 28th Paris Air Show na etiti 1969, ebe e gosipụtara ya ọha na eze na nke mbụ ya. The 747 natara ya FAA airworthiness akwụkwọ na December 1969, clearing ya maka iwebata n'ime ọrụ.  Ajụjụ: Olee nsogbu ndị bịaara ha?
engine stalls mere site ngwa ngwa throttle mmegharị na distortion nke turbine casings mgbe a obere oge nke ọrụ