Narrative:

Preflight at ZZZ showed all cowlings and doors secured. Cruise speed 190 KTS. Upon reaching 200 KTS in descent, small shudder and vibration began coming from left engine area. Alternator for deice equipment failed on left side. All other engine indications normal. Upon arrival at sgf, postflt found accessory gear box door on top of engine missing. I believe internal latch on gear box door may not have been fully latched. This could not be determined from outside preflight. Callback conversation with reporter revealed the following information: the reporter stated this door is located on the top of the engine nacelle and is used to service the engine and gear box oil. The reporter said the crew cannot see the door and can only see the latch handles on each side of the nacelle. The reporter stated the mechanics in ZZZ advised the reporter that the door needed work as it had to be wiggled to get closed and latched. The reporter stated when the door departed it left a portion of the door and one latch intact, still latched.

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Original NASA ASRS Text

Title: AN FK27-500 IN DSCNT AT 8000 FT HAD #1 ENG GEAR BOX ACCESS DOOR DEPART THE ACFT.

Narrative: PREFLT AT ZZZ SHOWED ALL COWLINGS AND DOORS SECURED. CRUISE SPD 190 KTS. UPON REACHING 200 KTS IN DSCNT, SMALL SHUDDER AND VIBRATION BEGAN COMING FROM L ENG AREA. ALTERNATOR FOR DEICE EQUIP FAILED ON L SIDE. ALL OTHER ENG INDICATIONS NORMAL. UPON ARR AT SGF, POSTFLT FOUND ACCESSORY GEAR BOX DOOR ON TOP OF ENG MISSING. I BELIEVE INTERNAL LATCH ON GEAR BOX DOOR MAY NOT HAVE BEEN FULLY LATCHED. THIS COULD NOT BE DETERMINED FROM OUTSIDE PREFLT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THIS DOOR IS LOCATED ON THE TOP OF THE ENG NACELLE AND IS USED TO SVC THE ENG AND GEAR BOX OIL. THE RPTR SAID THE CREW CANNOT SEE THE DOOR AND CAN ONLY SEE THE LATCH HANDLES ON EACH SIDE OF THE NACELLE. THE RPTR STATED THE MECHS IN ZZZ ADVISED THE RPTR THAT THE DOOR NEEDED WORK AS IT HAD TO BE WIGGLED TO GET CLOSED AND LATCHED. THE RPTR STATED WHEN THE DOOR DEPARTED IT LEFT A PORTION OF THE DOOR AND ONE LATCH INTACT, STILL LATCHED.

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.