Risk assessment of fuel quantity indicator replacement in ATR 72 aircraft

Aircraft maintenance activities are rife with opportunities for error. The concurrent in-flight failure of all of the engines of a non-scheduled airline flight and the following list of human lives highlight one of these opportunities. As commonly recognized among flight operators, each flight safety agency follows the criteria of the International Civil Aviation Organization Annex 16 in which all the evidences of the technical investigation pave the way for avoiding future flight accidents or incidents. On the other hand, when the Italian penal procedure code was applied for the Tuninter aircraft ATR 72 (identification code TS-LBB) crash at issue on 6 August 2005 near Palermo (Italy), the investigation is also carried out for finding (if concurrent or not) the personal and professional responsibilities. This was the task of the first author (R.M.A.M.). Now, this article briefly reports the findings of the investigation and discusses more in detail how both human factors of design and human factors in the published instructions for the completion of a maintenance task contributed to this accident.