Although not directly related to the OAT error which caused this incident, is anyone else reading this thread and the AAIB report wondering why it took the pushback crew to notice the nose gear tyres were so badly worn they both needed replacing before the airplane actually departed ? Surely an item that should have been spotted on the crews pre-flight inspection of the airplane. Did they miss it, or if they notice it, did they still deem the airplane airworthy ? Who would the pushback crew inform after they noticed this, apart from the crew ? And who would make the actual call to have them changed ? The crew or operator ? To me that points to lack of attention to detail and preparation. Maybe the FMC programming suffered the same way. Just a thought.