As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) UNUSUAL SOUND HEARD FROM THE A/C ON COOL DOWN COMING FROM THE ENGINE INLET AREA. UPON FURTHER INVESTIGATION THE COMPRESSOR HAD FOD. A NUTPLATE ON THE FORWARD SIDE OF THE PARTICLE SEPERATOR, THAT FASTEN THE FOWARD INLET COWLS ON, HAD SPLIT AND HALF OF THE NUT PLATE WENT THRU THE PARTICLE SEPERATOR AND WAS INGESTED BY THE ENGINE. THE NUT PLATE MADE IT THRU THRU THE ENTIRE ENGINE.