The operator reported that, during the initial climb, about 1,500 ft, the pilot and passengers reported hearing and feeling an impact. The upper left engine cowling separated and struck the windshield. The pilot declared an emergency, returned to the departure airport, and landed without further incident

Postaccident examination revealed traces of blood on the propeller, left wing leading edge, and the vertical stabilizer leading edge. The airplane sustained substantial damage to the empennage, which was consistent with impact damage from the separated engine cowling.

The operator reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.