Inquiry finds poor maintenance discipline and resource strain behind Voepass ATR 72 icing crash
Brazilian probe finds strained resources and pressure to meet flight schedules meant aircraft were knowingly operated in degraded condition. Pressure to ensure continuous aircraft availability despite limited maintenance resources led to poor discipline at Brazilian carrier Voepass, with technical faults left unrecorded and unresolved, investigators have disclosed. Investigation authority CENIPA has highlighted the failure to record an airframe de-icing malfunction in the Voepass ATR 72-500 which fatally stalled as a result of ice accumulation on 9 August 2024. The aircraft was dispatched without restrictions imposed by the minimum equipment list being recorded. Despite the malfunction the ATR was flown through icing conditions on its service from Cascavel to Sao Paulo Guarulhos, entering a flat spin over Vinhedo from which it did not recover. CENIPA has detailed a pervasive, and normalised, culture of deviation from rigorous maintenance practices arising from limited resources – particularly at secondary bases – and the pressure to avoid disruption to aircraft schedules. This even went as far as recording malfunctions as having been resolved, without corrective work being performed, in order to release an aircraft to operation without minimum equipment list restrictions. When the system malfunctioned on a subsequent flight, says CENIPA, it would again be recorded in the technical logbook, thereby "establishing a new rectification deadline". "This conduct resulted in the successive renewal of the [minimum equipment list] item without effective correction of the malfunction, masking its chronic nature and postponing its definitive resolution," it adds. "There was also the practice of replacing an inoperative component with another known to be malfunctioning and dispatching the aircraft for flight." This would similarly enable a new malfunction entry, and continuation of operation based on the minimum equipment list. ‘Superficial manner’ CENIPA says mechanics usually had only a few hours, during night-shift periods, to perform corrective maintenance – especially complex tasks – on aircraft which were scheduled to operate flights the following morning. "The pressure placed on mechanics to expedite the release of aircraft conflicted with the lack of time available for troubleshooting and resolving failures reported in the [logbook]," says the inquiry, "thereby contributing to the performance of maintenance tasks in a superficial manner." CENIPA says maintenance of the de-icing system boots was conducted exclusively at the company's main base at Ribeirao Preto. Despite evidence of airframe de-icing system faults on immediately preceding flights, there was "no record" of such malfunctions in the logbook, it adds. The aircraft was dispatched on its flight to Sao Paulo, under the conditions of the minimum equipment list, with 10 inoperative items – but the airframe de-icing system was not among them. CENIPA's inquiry learned of maintenance problems including qualified personnel shortages, exhausting work schedules, and fatigue, contributing to a "climate of pressure" on mechanics. "At the secondary bases, since the infrastructure was limited, there was an 'operational standard' focused on releasing aircraft with inoperative items dispatched under the [minimum equipment list], with the expectation that definitive resolution of the malfunction would occur when the aircraft returned to the main base," it says. While this model did not, itself, amount to non-compliance with requirements, it led to situations in which deadlines expired with faults remaining unresolved. "In practical terms, these combined actions resulted in aircraft being operated under knowingly degraded conditions, exceeding the time limits established by the regulations in force," says the inquiry. Pressure on pilots CENIPA adds that there was a "culture" among flight crews of not recording malfunctions in the logbook. "It was possible to ascertain that these patterns of deviation were encouraged by the company and directed toward the pilots," it adds. "This informal process constituted a form of pressure on pilots in command, aimed at avoiding the recording of discrepancies that could result in the prolonged unavailability of the aircraft for flight due to the need to correct the reported failures." Problems with the de-icing system, which had been perceived by several crews prior to the accident, were a "clear example" of this absence of formal reporting, it adds. "This conduct evidenced the normalisation of operational deviations in the face of recurrent failures," it says. "This behaviour generated a recurring pattern of verbal communications between pilots and mechanics without proper technical recording." None of the 58 passengers and four crew members survived the crash. Voepass was grounded last year . ATR has responded to the inquiry's conclusions, stating that the accident "further demonstrates that adherence to maintenance, operational procedures and training are essential to prevent re-occurrence". "Flight safety is the primary responsibility of the commercial aviation system and all its stakeholders," it says.
