First of all, lucky it did not bring down an airliner. Scary to think about the potential outcome.
Would be interesting to know if it was an unintentional release (finger-trouble), launched as either a MADDOG or against a FCR target by mistake, or if it was an inadvertent release caused by a system malfunction. If not an airliner it could have been Pierre flying around in his Deux Mille, acting as opponent on a 2v2 training sortie, sucking it up or defeating it with electrons.
Would also be interesting to know how the Amraam is mech'ed on the Typhoon, and what procedures Pedro has in place for training flights with live missiles.
In the Viper it takes at least four switch actions to fire the Amraam. Select Master Arm switch to ARM, select A/A mastermode (or MSL OVRD/DGFT mode), designate on a target to get a FCR lock (or depress and hold manual range/uncage for MADDOG), press the pickle button. I assume its roughly the same steps in the Typhoon.
I always regarded flying an armed QRA jet as redair, on A/A training sorties as an accident waiting to happened, yet in my airforce we do it on a day to day basis. Of course we have procedures in place and so on, but it does not take more then a short lapse in concentration, in the heat of the fight, to forget that one has live missiles under the wings. It has happened before and it will probably happened again.