Narrative:

We had just leveled off after departing det (altitude 2500' MSL, 160 KIAS). We were on the second flight of the day. A loud bang was heard and the aircraft shuddered. We reduced airspeed to 130 KTS and checked flight controls. The aircraft felt smooth and responsive. The bang was caused by the right engine inboard accessory inspection hatch separating from the airframe and taking part of the top cowling with it. We returned to pontiac and landed west/O incident. We later discovered that a safety communication had been issued on this subject prior to our taking over operation of this aircraft. The aircraft logs were searched and no mention was made of any compliance with the communication. A copy is included with this report. An FAA form 8010-4 malfunction or defect report was filed by our maintenance indicating that the communication had been complied with based on inspection of the other 3 remaining inspection hatches, all of which were found in need of adjustment. The safety communication does not stress the 'leading edge protruding' into the slipstream enough. The design is poor to start with and the adjacent surfaces and not just the fastener fit adjustment. Fortunately no personal injury or damage was caused.

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Original NASA ASRS Text

Title: INSPECTION HATCH ON ENGINE COWLING TORE OFF ACFT IN FLT.

Narrative: WE HAD JUST LEVELED OFF AFTER DEPARTING DET (ALT 2500' MSL, 160 KIAS). WE WERE ON THE SECOND FLT OF THE DAY. A LOUD BANG WAS HEARD AND THE ACFT SHUDDERED. WE REDUCED AIRSPD TO 130 KTS AND CHKED FLT CONTROLS. THE ACFT FELT SMOOTH AND RESPONSIVE. THE BANG WAS CAUSED BY THE RIGHT ENG INBOARD ACCESSORY INSPECTION HATCH SEPARATING FROM THE AIRFRAME AND TAKING PART OF THE TOP COWLING WITH IT. WE RETURNED TO PONTIAC AND LANDED W/O INCIDENT. WE LATER DISCOVERED THAT A SAFETY COMMUNICATION HAD BEEN ISSUED ON THIS SUBJECT PRIOR TO OUR TAKING OVER OPERATION OF THIS ACFT. THE ACFT LOGS WERE SEARCHED AND NO MENTION WAS MADE OF ANY COMPLIANCE WITH THE COMMUNICATION. A COPY IS INCLUDED WITH THIS RPT. AN FAA FORM 8010-4 MALFUNCTION OR DEFECT RPT WAS FILED BY OUR MAINT INDICATING THAT THE COMMUNICATION HAD BEEN COMPLIED WITH BASED ON INSPECTION OF THE OTHER 3 REMAINING INSPECTION HATCHES, ALL OF WHICH WERE FOUND IN NEED OF ADJUSTMENT. THE SAFETY COMMUNICATION DOES NOT STRESS THE 'LEADING EDGE PROTRUDING' INTO THE SLIPSTREAM ENOUGH. THE DESIGN IS POOR TO START WITH AND THE ADJACENT SURFACES AND NOT JUST THE FASTENER FIT ADJUSTMENT. FORTUNATELY NO PERSONAL INJURY OR DAMAGE WAS CAUSED.

Data retrieved from NASA's ASRS site as of August 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.