As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) BLACK SOOT NOTED ON RIGHT HAND OUTBOARD LANDING GEAR DOOR AND OUTBOARD COWL FLAP. EXHAUST STACK FOUND SEPARATED. NO OTHER LOOSE AREAS NOTED. SUBMITTER SUGGESTS THAT THE REAR STACK WAS TOO SHORT AND THE SPRING ACTION OF REAR SUPPORT CAUSED THE SEPARATION OR VIBRATION OR BACK FIRE ON PREVIOUS START.