THE PURPOSE OF THE FLT WAS TO CHECK THE ACFT AFTER REPLACING A WOODEN PROP WITH AN ALL METAL PROP & TO PREPARE FOR ENTRY IN THE RENO AIR RACES. BFR ENTERING THE AIR RACES. THE PLT NEEDED TO DEMONSTRATE HIS ABILITY TO MAKE A 'BARREL ROLL' & TO MAKE 3 LNDGS. THERE WAS NO OPERABLE RADIO IN THE ACFT, SO THE PLT USED A HAND HELD VHF TRANSCEIVER. AFTER HE TOOK OFF, RADIO COMM WITH THE ACFT WAS LOST, SO TWR PSNL USED VISUAL LGT SIGNALS FOR CONTROL. THE PLT MADE 2 TOUCH-&-GO LNDGS & HAD BGN A DSCNDG TURN TO FINAL APCH (3RD PATTERN), WHEN THE ACFT ROLLED INVERTED & PLUNGED TO THE GND. ONE WITNESS THOUGHT THE ACFT SNAP ROLLED. ANOTHER SAID IT WAS SWAYING FM SIDE TO SIDE AS IT PLUNGED TO THE GND. IT CRASHED IN A NOSE DWN ATTITUDE & THERE WAS LITTLE MOVEMENT AFTER IMPACT. NO PREIMPACT PART PROBLEM WAS FND. THE PLT'S BLOOD WAS CHECKED AT 2 LABS. ONE CHECK SHOWED AN ALCOHOL LVL OF 0.238%; THE OTHER SHOWED A LVL OF 0.200%. A CHECK OF THE PLT'S URINE SHOWED AN ALCOHOL LVL OF 0.207%. THE ARPT ELEV WAS 4151 FT.