Narrative:

Aircraft was used as a propeller for filming and 'police' emblems were attached, by peel and stick type backing adhesive, to various doors and cowlings. One sticker of concern was affixed to the left-hand lower engine cowling and didn't appear to adhere well along the bottom due to protruding rivet heads along the bottom of that cowling. It was of concern to me that this may 'catch air' and be peeled off in flight. I pushed on the emblem and rubbed my hands across it several times to test its adhesion. During these checks, the cowling gave no indication of movement as if unsecured or being unlatched. The preflight had been accomplished previously. During a flight to the filming site, some turbulence was encountered and avoidance of a large bird was necessary by banking the aircraft to the right. It was during this maneuver that personnel on the ground saw 'something' (the cowling) depart the aircraft or otherwise fall toward the ground--its actual point of impact being obscured by the terrain and vegetation. Upon landing, it was apparent the left lower cowling was gone and had pulled away cleanly from the hinge support assembly with no damage to the aircraft. When located and retrieved, the cowling damage was noted to be minimal with only slight cracks radiating from 2 of the screw-rivet holes and the remaining holes to be enlarged and distorted slightly from the rivets pulling out of the cowl assembly backing. Also noted when found: the forward latch was open or unlatched and the rear latch was still closed in the latched position. The cowling was repaired and returned to service. Though the forward latch appears slightly worn, it is my belief that it was latched closed or seemed to be after preflight. The additional inspection of the emblems would certainly have indicated an unlatched condition by movement of the cowl. However, I wonder at the alignment of the latch and at the possibility of it being slightly or merely jammed some way, appearing to be fastened and ready at the slightest jolt or flexing to come unfastened. It is now standard procedure to double-check all latches and hinges, to ensure they are working properly.

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Original NASA ASRS Text

Title: HELICOPTER PLT AVOIDS BIRDS, LATER DISCOVERS COWLING SEPARATED FROM ACFT.

Narrative: ACFT WAS USED AS A PROP FOR FILMING AND 'POLICE' EMBLEMS WERE ATTACHED, BY PEEL AND STICK TYPE BACKING ADHESIVE, TO VARIOUS DOORS AND COWLINGS. ONE STICKER OF CONCERN WAS AFFIXED TO THE LEFT-HAND LOWER ENG COWLING AND DIDN'T APPEAR TO ADHERE WELL ALONG THE BOTTOM DUE TO PROTRUDING RIVET HEADS ALONG THE BOTTOM OF THAT COWLING. IT WAS OF CONCERN TO ME THAT THIS MAY 'CATCH AIR' AND BE PEELED OFF IN FLT. I PUSHED ON THE EMBLEM AND RUBBED MY HANDS ACROSS IT SEVERAL TIMES TO TEST ITS ADHESION. DURING THESE CHKS, THE COWLING GAVE NO INDICATION OF MOVEMENT AS IF UNSECURED OR BEING UNLATCHED. THE PREFLT HAD BEEN ACCOMPLISHED PREVIOUSLY. DURING A FLT TO THE FILMING SITE, SOME TURB WAS ENCOUNTERED AND AVOIDANCE OF A LARGE BIRD WAS NECESSARY BY BANKING THE ACFT TO THE RIGHT. IT WAS DURING THIS MANEUVER THAT PERSONNEL ON THE GND SAW 'SOMETHING' (THE COWLING) DEPART THE ACFT OR OTHERWISE FALL TOWARD THE GND--ITS ACTUAL POINT OF IMPACT BEING OBSCURED BY THE TERRAIN AND VEGETATION. UPON LNDG, IT WAS APPARENT THE LEFT LOWER COWLING WAS GONE AND HAD PULLED AWAY CLEANLY FROM THE HINGE SUPPORT ASSEMBLY WITH NO DAMAGE TO THE ACFT. WHEN LOCATED AND RETRIEVED, THE COWLING DAMAGE WAS NOTED TO BE MINIMAL WITH ONLY SLIGHT CRACKS RADIATING FROM 2 OF THE SCREW-RIVET HOLES AND THE REMAINING HOLES TO BE ENLARGED AND DISTORTED SLIGHTLY FROM THE RIVETS PULLING OUT OF THE COWL ASSEMBLY BACKING. ALSO NOTED WHEN FOUND: THE FORWARD LATCH WAS OPEN OR UNLATCHED AND THE REAR LATCH WAS STILL CLOSED IN THE LATCHED POS. THE COWLING WAS REPAIRED AND RETURNED TO SVC. THOUGH THE FORWARD LATCH APPEARS SLIGHTLY WORN, IT IS MY BELIEF THAT IT WAS LATCHED CLOSED OR SEEMED TO BE AFTER PREFLT. THE ADDITIONAL INSPECTION OF THE EMBLEMS WOULD CERTAINLY HAVE INDICATED AN UNLATCHED CONDITION BY MOVEMENT OF THE COWL. HOWEVER, I WONDER AT THE ALIGNMENT OF THE LATCH AND AT THE POSSIBILITY OF IT BEING SLIGHTLY OR MERELY JAMMED SOME WAY, APPEARING TO BE FASTENED AND READY AT THE SLIGHTEST JOLT OR FLEXING TO COME UNFASTENED. IT IS NOW STANDARD PROC TO DOUBLE-CHK ALL LATCHES AND HINGES, TO ENSURE THEY ARE WORKING PROPERLY.

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.