As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DIPSTICK VIBRATED LOOSE DURING SUSTAINED INVERTED FLIGHT AND 4 QUARTS OF OIL WERE LOST. ENGINE HAD OPERATED NORMALLY FOR 30 MINUTES OF AEROBATIC FLIGHT AND 30 MINUTES OF NORMAL FLIGHT BEFORE LOOSENING. ENGINE MANUFACTURER AND AIRCRAFT BUILDER DO NOT PROVIDE INFORMATION AS TO PROPER TIGHTENING OF THIS PORT IN OPERATOR'S MANUELS.