There has been much discussion as to whether faulty software or Electromagnetic Interference (EMI) played a part in this accident. Before we can ascribe fault to either, we need to know just what the software does. The fuel control has multiple inputs but, presumably, only two outputs, fuel metering valve and inlet guide vane positioning, both of which have been reported by the AAIB to have functioned properly.
What else does the fuel control ultimately do? If the fuel control does more, can someone help us out here? If not, to blame the software or EMI looks to me like barking up the wrong tree. Again, apparently appropriate electrical signals reached the engines and individual parts of the engines responded accordingly but the engines just didn't produce the demanded power.
If there are no other fuel control outputs, it would seem that, since the high-pressure fuel pumps have been reported by the AAIB to work normally and there was enough fuel flow to keep the engines running at just above flight idle, it boils down to some characteristic of the fuel which reduced its ability to burn properly OR some flow restriction, presumably upstream of the high-pressure pumps.
Of course, there is a
third possibility, the tanks simply started to run dry.
