Hang on... he said "650C" ... hmmm freezing is 32F and 0C and boiling is 100C and 212F, right?
So we double it and add 30? Or is that just for speed limits?
Steel will soften at high temperatures (1000+ "normal" degrees) but a jet fuel fire won't do that, and like Will says it was a big burst of flame and a much lesser continous fire. Bet you could have touched those beams after that initial blast.