Today Spanair announced that the reason for returning to the gate was the heating system of the temperature sensor. In other words the heating to prevent ice getting on the temperature probe. It was disactivated by the mechanic according to the MEL. The airplane is aloud to fly with it for 10 days before it needs to be repaired. Since the weather was good and there were no icing conditions the decision to depart was correct if what Spanair sais is correct.
The mechanic is 41 years old and has 20 experience. He is at home with a depression after the accident. I sure feel sorry for him.
The take of was filmed and there were no visible flames from the engine and some sources now say it was the right engine.
It will take some time before we will know what happened but for sure it is an extremely said event.