2 ms·

Aren't all these scenarios tested in simulators and in the actual aircraft? If it's not possible to recover the aircraft why was this not know and why was this

• acqq 8y ago
  > Aren't all these scenarios tested in simulators and in the actual aircraft? In this case the answer is, no: "During nine to 12 months of MAX flight testing, test pilots injected errors into the flight system that tested stall conditions and runaway stabilizer, among other scenarios, the people said. But no one was aware of a specific test of an MCAS failure mode triggered by erroneous sensor data." March 29, https://www.reuters.com/article/us-ethiopia-airplane-boeing-analysis/no-call-for-simulators-in-new-boeing-737-max-training-proposals-idUSKCN1RA006 https://www.reuters.com/article/us-ethiopia-airplane-boeing-...
• prewett 8y ago
  Planes are complicated, and you can't test for all n! different things that can go wrong. I think the case that: a) an MCAS sensor is giving incorrect data AND b) the data is leading MCAS to set the trim to the max AND c) the plane is going so fast that the force of the air over the elevator is too great to manually override AND d) the plane is too low to temporarily drop altitude to reduce the force on the elevator to allow a manual override I don't think this is an obvious set of things to foresee happening, especially D. It's the same way with software. There's just too many things to think of, and errors that slip through the test cases are inevitable. I've had what I've considered to be pretty thorough test cases and had a bug that was "obvious". I'm not excusing Boeing, but it isn't gross incompetence either.