What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
Narrative: the pilot stated that he was at cruise altitude (9,000 MSL) when he experienced a vibration in the #1 engine. The pilot reduced power then leaned and enriched the mixture with no effect. The aircraft was 3 miles and 9,000' MSL from mke. Engine was secured and as a precautionary measure the aircraft was landed with out further incident. The chief mechanic for C8AA, Mr. N.b. umpstead arrived and performed maintenance on the #1 engine. The mechanic replaced a bad spark plug. (Champion rem 40E). The engine was operationally tested and returned to service.
As the FAA filed it
NARRATIVE: THE PILOT STATED THAT HE WAS AT CRUISE ALTITUDE (9,000 MSL) WHEN HE EXPERIENCED A VIBRATION IN THE #1 ENGINE. THE PILOT REDUCED POWER THEN LEANED AND ENRICHED THE MIXTURE WITH NO EFFECT. THE AIRCRAFT WAS 3 MILES AND 9,000' MSL FROM MKE. ENGINE WAS SECURED AND AS A PRECAUTIONARY MEASURE THE AIRCRAFT WAS LANDED WITH OUT FURTHER INCIDENT. THE CHIEF MECHANIC FOR C8AA, MR. N.B. UMPSTEAD ARRIVED AND PERFORMED MAINTENANCE ON THE #1 ENGINE. THE MECHANIC REPLACED A BAD SPARK PLUG. (CHAMPION REM 40E). THE ENGINE WAS OPERATIONALLY TESTED AND RETURNED TO SERVICE.