Asiana flight crash at San Francisco
Suninmyeyes has probably got it close. It seems fairly obvious the aircraft got low and slow, impacting with a high angle of attack, the question of course is why that should happen on such a benign day.
My guess is that the crew were relying on the A/T to control their speed and failed to notice it wasn't . I know there will be howls,especially from those gents who flew older stuff about poor flying skills but I think that those of us who are completely honest with ourselves and fly modern aircraft like the 777 and the Airbus would admit that scanning the engine indications has almost dropped out of the scan pattern and that speed is perhaps not as well scanned as it should be.
Not for one second saying this is how it SHOULD be just being realistic. For most operators the crews are forbidden from practising A/T off approaches ( despite a U/S A/T not being a no dispatch item).
So my guess would be that the A/T was in a mode which did not auto wake up or had dropped out or been disconnected and the crew failed to notice the speed decay. A cognitive failure could also cause someone to press the A/T disconnect on the side of the thrust lever rather than the TOGA on the front of the thrust lever.