Alaska Airlines 737 Possibly Left Boeing Factory Without Bolts, N.T.S.B. Says The N.T.S.B. revealed that a photo suggests bolts in a fuselage panel were taken out at a Boeing factory but not replaced. Four bolts securing the panel were removed at the Renton, Wash., factory and may not have been reinstalled, leading to the panel blowing off during a recent flight. The report did not identify who removed the bolts, but it indicated that not all bolts were put back after repairs. A photo from the N.T.S.B. showed three missing bolts and one covered with insulation. The safety board found no evidence that the panel was opened again after leaving the factory. The plane was delivered to Alaska Airlines in October. Source: https://ift.tt/zRrTI79