As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WITH AC EXTERNAL SELECTED ON BATT BUS, CAPT AND F/O ON BOARD PERFORMING PRE FLT DUTIES, OBSERVED A RUSHING AIR SOUND, COCKPIT AND FED CABIN QUICKLY FILLED WITH SMOKE. EXTERNAL AC WAS DE-SELECTED AND BATT TURNED OFF. WHILE EXITING A/C, FIRE WAS OBSERVED PENETRATING A/C SKIN AFT OF CAPT SIDE WINDOW.