ariane V failure
to llondel...
Ariane V failure was definately a software failure.
Without going into details the onboard computers
contained inertial reference software which was not
needed after launch. On Ariane IV which it was designed for
it was normally left running, this practice also used on V.
Due (I remember) to higher slew rate of the short fat Ariane V
some kind of data conversion error occured. This caused
an error to be presented to the flight computer, which in turn
demanded full delection of the motors, ie game very over.
Someone will correct me I'm sure.
Lessons to be learned....
At least try to validate under flight conditions, but I'm not
sure how that would relate to aviation software