737 MAX FLIGHT CONTROL SYSTEM INSTALL
737 MAX FLIGHT CONTROL SYSTEM MANUAL
737 MAX FLIGHT CONTROL SYSTEM SOFTWARE

737 MAX FLIGHT CONTROL SYSTEM MANUAL

5īoeing decided pilots were the 'backup' for MCAS, but the company did not explain in the 737 MAX operations manual how MCAS worked and how little time pilots had to respond. Lion Air did not relay to the pilots that crashed the next day the seriousness of the repair or details of a near-disaster on the prior flight, narrowly avoided with help from a third pilot who knew about MCAS and happened to be in the cockpit. 13 Indeed, the day before the Lion Air crash, a maintenance worker had replaced a malfunctioning sensor. 9 A 2018 Boeing memo also revealed pilots had only four seconds to recognize an MCAS misfire and 10 seconds to correct it. 14 The external sensor was prone to damage from birds as well as errors in maintenance and calibration. Yet, in 2015, Boeing documented MCAS was vulnerable to sensor failure. In particular, the final design-with one sensor-assumed pilots could intervene if data was faulty or if anything else went wrong with MCAS. Boeing engineers also continually increased the power of MCAS to push down the nose of the aircraft, without changing assumptions about data and safety. However, one sensor was cheaper and simpler, and that became the final design. The original MCAS design had two external 'angle of attack' (AOA) air sensors, one on each of the outer sides of the aircraft.

737 MAX FLIGHT CONTROL SYSTEM SOFTWARE

The idea was that MCAS software would enable the 737 MAX to emulate the handling characteristics of the 737NG model by pushing down the front of the plane when sensor readings indicated the nose was too high.

737 MAX FLIGHT CONTROL SYSTEM INSTALL

Rather than redesign the plane, Boeing chose to install MCAS, which it adapted from another aircraft. But the new engines significantly changed the pitch angle and stability of the older 737. Boeing was responding to intense competition from Airbus and demand from airline customers for more fuel-efficient, single-aisle planes. The company wanted to put bigger, more fuel-efficient engines on an older aircraft, the 737NG (Next Generation). We can start with Boeing's decision to deploy MCAS. In a series of decisions, they put profits before safety, did not think through the consequences of their actions, or did not speak out loudly enough when they knew something was wrong. Nonetheless, executives, managers, and engineers at Boeing were not stumped by the complexity or unpredictability of a new technology. Were the 737 MAX crashes truly a failure of technology, an advanced aircraft-control system? Or was it a failure of management? Of course, at many levels, technology and management are inseparable. A technical system failure was the proximate cause of the disasters, which cost billions of dollars in losses to Boeing and the airlines, and, much more tragically, the lives of 346 passengers and crew.įounded in 1916, Boeing remains one of the world's most renowned engineering companies. The 737 MAX had been Boeing's fastest-selling plane in history before government authorities worldwide grounded the fleet of nearly 400 aircraft-but only after the second crash. 5 The report blamed the two crashes in October 2018 (Lion Air, in Indonesia) and January 2019 (Ethiopian Airlines, in Ethiopia) on the computerized flight-control system called Maneuvering Characteristics Augmentation System (MCAS). House of Representatives released a 238-page report on the 737 MAX debacle, concluding an 18-month investigation. Federal Aviation Administration cleared the Boeing 737 MAX for flight, but the history of how Boeing got to this point remains disturbing.

737 max flight control system