- The Seattle Times says it identified flaws in an internal safety analysis of the 737 Max’s MCAS software and had presented them to Boeing and the Federal Aviation Administration four days before the second fatal crash in five months involving the plane model.
- According to The Times, internal documents from Boeing misrepresented some features of the software being investigated as a possible cause in both the recent Ethiopian Airlines crash and that of Lion Air in October.
- MCAS is designed to pitch the plane’s nose down if it detects a stall, but investigators think the system could be falsely triggered.
Safety concerns involving Boeing’sMCAS software – the program under scrutiny following the recent crashes of two of Boeing’s 737 Max aircraft – were presented to both the company and the Federal Aviation Administration four days before the fatal Ethiopian Airlines crash last Sunday, The Seattle Times reported on Sunday.
The Times said it had identified issues with an internal safety report that was used as part of the plane model’s FAA certification. The paper cited current and former engineers involved or familiar with the report, which analysed the MCAS, or Manoeuvring Characteristics Augmentation System, software.
The MCAS software in place on newer 737 Max jets is being investigated as a possible cause in both the March 10 Ethiopian Airlines crash as well as the Lion Air crash in October. MCAS is designed to point the plane’s nose downward if conditions suggest the plane might stall. The feature was added because the new Max’s larger, more fuel-efficient engines disrupted the plane’s center of gravity, changing the way it would handle for pilots.
The Times said the internal report, however, “understated the power of the new flight control system,” “failed to account for how the system could reset itself each time a pilot responded,” and rated the severity of a system failure as being at a level that “should have precluded activation of the system based on input from a single sensor.”
While the causes of both crashes are unclear, evidence has suggested pilots from both planes might have fought against the MCAS system in the minutes before the planes crashed. Because the system is linked to a single sensor, observers have speculated that sensor issues might have caused the feature to activate mistakenly.
On Sunday, Ethiopia’s transport minister said the two crashes had “clear similarities.”
Boeing and federal officials have denied reports that a software update started after the October crash and now set to be released as soon as April was delayed because of the government shutdown earlier this year.
“While investigators continue to work to establish definitive conclusions, Boeing is finalising its development of a previously-announced software update and pilot training revision that will address the MCAS flight control law’s behaviour in response to erroneous sensor inputs,” CEO Dennis Muilenburg said in a statement Sunday.
The Times said it presented both Boeing and the FAA with the problems it identified in the safety report four days before the March 10 crash.
The company did not immediately respond to question from Business Insider about the timing of The Times’ questions.
The FAA declined to comment.
More about the investigation into Boeing’s 737 Max aircraft:
- The US government has reportedly subpoenaed a Boeing employee following the 737 Max’s two deadly crashes
- Boeing pauses 737 MAX deliveries in wake of deadly crashes
- US government reportedly investigating the FAA’s approval process of Boeing 737 Max planes
- Ethiopian Airlines and Lion Air crash black boxes reportedly showed ‘clear similarities,’ according to transport minister
- The government’s grounding of all Boeing 737 Max jets is a reminder that the US still doesn’t have a leader for its top air safety agency
- The worst outcome for Boeing after two deadly crashes involving its 737 Max 8 aircraft could lead airlines to lose trust in the company, an expert says
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