This plane had been flying air races since the '40s. Had been heavily modified. I heard from a pilot friend that some recent additional modifications had been done. It was thought that a hose on cooling system failed in some fashion allowing some sort of toxic (don't know what might have been used) coolant/material loose that took out the pilot. Is why we now have coolant rules about flammability/toxicity. And yes, it might be death knell for Reno.
An additional note: The aircraft was carrying ~90 gallons of race gasoline, 30 gallons of ADI fluid, and ~90 gallons of boil-off fluid at the time of the accident. Both ADI and boil-off are ~50-50 methanol and water. On impact, the 90 gal of fuel, 60 gal of methanol, and 60 gal of water vaporized. The water content was sufficient to prevent any fire or explosion.
This would not be true of aircraft not using large amounts of ADI and boil off. Post crash injuries may have been far worse without this modification to the cooling system that essentially converted a potential explosion into its own extinguisher.
