Narrative:

On rotation loud thump was heard under fuselage. Pilot presumed bird or animal strike, or other object. Pilot called tower, returned for low pass for landing gear check. Tower reported observer on field stated gear was intact. Pilot then returned to land. When asked by tower if emergency equipment needed, pilot decided yes. Pilot landed plane, inspected plane, gave pertinent data to fire crash crew, took off and flew to destination. On daylight inspection plane was found to have missing cowl flap assembly, torn off by strike or defect! We do not know at present, could not find parts to date. Callback conversation with reporter revealed the following: the problem was loss of cowling flap door due to hinge pin coming out. Not certain if caused by improper maintenance or failure of the pin. Ascertained was single engine aircraft and pilots license type and location of incident.

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Original NASA ASRS Text

Title: GA SMA LOST ENGINE COWLING FLAP DOOR ON TKOF. RETURN AND LAND, THEN ILLEGAL FLT TO DESTINATION WITH PART MISSING.

Narrative: ON ROTATION LOUD THUMP WAS HEARD UNDER FUSELAGE. PLT PRESUMED BIRD OR ANIMAL STRIKE, OR OTHER OBJECT. PLT CALLED TWR, RETURNED FOR LOW PASS FOR LNDG GEAR CHK. TWR RPTED OBSERVER ON FIELD STATED GEAR WAS INTACT. PLT THEN RETURNED TO LAND. WHEN ASKED BY TWR IF EMER EQUIP NEEDED, PLT DECIDED YES. PLT LANDED PLANE, INSPECTED PLANE, GAVE PERTINENT DATA TO FIRE CRASH CREW, TOOK OFF AND FLEW TO DEST. ON DAYLIGHT INSPECTION PLANE WAS FOUND TO HAVE MISSING COWL FLAP ASSEMBLY, TORN OFF BY STRIKE OR DEFECT! WE DO NOT KNOW AT PRESENT, COULD NOT FIND PARTS TO DATE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: THE PROB WAS LOSS OF COWLING FLAP DOOR DUE TO HINGE PIN COMING OUT. NOT CERTAIN IF CAUSED BY IMPROPER MAINT OR FAILURE OF THE PIN. ASCERTAINED WAS SINGLE ENG ACFT AND PLTS LICENSE TYPE AND LOCATION OF INCIDENT.

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.