About how hot jet fuel burns... I have seen videos and pictures of jets burning. The metal completely melts and desintegrates. Granted, most of the aircraft is aluminum, and I don't know much about the melting point of aluminum compared to steel, but this all happens in a matter of minutes. Jet fuel (JP-8) is hard to ignite, but once it is ignited, it burns really well.
Found the melting points: steel-1510 degrees C (2750°F). Aluminum- 660.37 °C (933.52 °K, 1220.666 °F)
And about government conspiracies... of course they exist! Do you think that it would be good to know everything our government knows? I don't think so.