Years ago a airplane landed on a highway (Manitoba or Ontario), that plane lost all its engines. It was able to land because it could glide. Most planes designed today, are not made to glide. it needs a powerplant/engine to push it through the air and generate lift on its wings. If you need to know more search stall airplane.
If you have been in a nice new car, and seen all the electronic gadgets in them, well the same goes for your engine electronics too. In the past to measure something you had a analog meter that gave a pretty good indication of what was being measured. Nowadays the meter could be something else. for temperature its a thermo-couple (which has to be calibrated). this thermo-couple might not be where you think its gonna be. An oil temperature gauge, could be on the outside of the oil pan, not in the oil itself. Its an indirect way of measuring to save money on time, design, and maintenance.
Planes are no different. the meters are inputs for computer programs (which means the analog is converted to digital by some means). The program (algorithm) takes digital inputs; puts it through its logic centers and comes out with a response. If a digital meter fails and that is crucial to the program, it can adversely affect the output the program is responsible for. The response for all these system is either P, PI, PID control, depending on the set point or parameters you need. Bad input can mean really bad output from a controller.... This is bad enough on stationary systems, let alone an airplane moving through the air.
The crash could be a variety of parameters; to make the plane go wonky after takeoff.
Whatever it is, Boeing sure fucked up somewhere, cause they usually are better than this ...
Just to note my college physic teacher told me that elevators have a safety factor of 10. Meaning that if the weights says 2000 lbs, it is tested for 20,000 lbs. I think he mentioned the safety factor for planes was between 1 and 3.
