As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING FLIGHT 2737 OUT OF MSP, LT ENGINE COWLING CAME LOOSE INFLIGHT. AIR RETURN TO MSP. MAINTENANCE REMOVED AND REPLACED UPPER FAIRING P/N 7254501-88 AND PROP IAW SAAB 340 JOB CARD 6110-303. REINSTALLED FIGURE 8 COWL AS REQUIRED. RE-SCUFFED METAL, PRIMED AND PAINTED IAW SAAB AMM 51-20-00.