Narrative:

During transition from climb to cruise, top half of engine cowl came loose on right side. Cowl blew back against windshield obscuring visibility ahead. I called gary tower and declared emergency, requesting runway 30. Return flight was uneventful since left side of cowl remained secure and wind pressure held it in place against the windshield even after landing. I had removed the cowl prior to flight for visual inspection of engine. The cowl on this model does not fit well, necessitating several trips from left to right side of aircraft. I believe that I must have failed to finally secure the right side. A proper preflight inspection should have disclosed this. Collateral damage: cracked windshield, destroyed the cowl, and some trailing edge damage on both propeller blades. Callback conversation with reporter revealed the following information: pilot indicated the propeller was replaced, the engine given a top overhaul and the windshield replaced. He indicated he was only about 3 mins from the airport where he landed. The aircraft is now back in service.

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Original NASA ASRS Text

Title: PA28 PLT HAD THE TOP COWLING OF A PA28 CAME OPEN INFLT AFTER IT WAS IMPROPERLY REINSTALLED.

Narrative: DURING TRANSITION FROM CLB TO CRUISE, TOP HALF OF ENG COWL CAME LOOSE ON R SIDE. COWL BLEW BACK AGAINST WINDSHIELD OBSCURING VISIBILITY AHEAD. I CALLED GARY TWR AND DECLARED EMER, REQUESTING RWY 30. RETURN FLT WAS UNEVENTFUL SINCE L SIDE OF COWL REMAINED SECURE AND WIND PRESSURE HELD IT IN PLACE AGAINST THE WINDSHIELD EVEN AFTER LNDG. I HAD REMOVED THE COWL PRIOR TO FLT FOR VISUAL INSPECTION OF ENG. THE COWL ON THIS MODEL DOES NOT FIT WELL, NECESSITATING SEVERAL TRIPS FROM L TO R SIDE OF ACFT. I BELIEVE THAT I MUST HAVE FAILED TO FINALLY SECURE THE R SIDE. A PROPER PREFLT INSPECTION SHOULD HAVE DISCLOSED THIS. COLLATERAL DAMAGE: CRACKED WINDSHIELD, DESTROYED THE COWL, AND SOME TRAILING EDGE DAMAGE ON BOTH PROP BLADES. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: PLT INDICATED THE PROP WAS REPLACED, THE ENG GIVEN A TOP OVERHAUL AND THE WINDSHIELD REPLACED. HE INDICATED HE WAS ONLY ABOUT 3 MINS FROM THE ARPT WHERE HE LANDED. THE ACFT IS NOW BACK IN SVC.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.