I just saw the Hindenburg episode and wanted to tell what I have heard about the ignition of the blaze. From an ex-military source I heard that the fire may have been started accidentally by a high-power military radar test. The arcing in the aluminum supports from this supposedly caused the burn, not only as a point source, but almost over the entire airship, creating the near instantaneous flash-burn. Hindenburg revisited?

why was the radar near the airship? and where did an arc like that come from?

This seems somewhat unlikely since the Hindenburg crashed in 1937 and no serious work was done on high power radar in the US until the Rad Lab was formed at MIT in 1940 and it would have require phenomenally large amounts of radiated power to induce arcing in the duralumin structure of the airship which wasn't available either.