Service difficulty report · Skin · Dhav DHC8102

Difficulty date
February 10, 2011
Submitted
March 15, 2011
Operation
Air carrier
Make and model
Dhav DHC8102
Aircraft time
47,824 hours
Engine
Pwa PW120A
Propeller
Hamstd 14SF7
Part
Skin
Condition
Delaminated
Location
Otbd Flap Lt
Part time
50,134 hours
Component
Flap · Bombdr
Component part number
85750244009
Stage of operation
IN
How discovered
V
Nature of condition
O
Precautionary procedure
K

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

CREW REPORTED, EXCEEDING 180 KNOTS WITH FLAP SELECTED AT 5 DEGREES. THIS WARRANTED A SPECIAL INSP AFTER EXCEEDING WING FLAPS DOWN SPEEDS IAW MM CHAP 05-50-51. FDR WAS PULLED AND A READ OUT SHOWED SPEEDS UP TO 195 KNOTS MOMENTARILY. DURING THE COURSE OF THE INSP, AME NOTICED SOME EXPOSED COMPOSITE IN A CORNER OF THE LT SIDE OTBD FLAP T/E. A SIMPLE TAP TEST LOOKED SUSPECT OF DISBOND IN THE AREA. EDDY CURRENT WAS CARRIED OUT ALONG THE SURFACE OF THE T/E AND IT REVEALED FURTHER DISBOND. T/E PN 85750244-009 WAS R & R. WE DO NOT BELIEVE THE FLAP OVERSPEED CONDITION WAS A CONTRIBUTING FACTOR TO THIS COMPOSITE DELAMINATION. HOWEVER MOISTURE INGRESSION WAS QUITE OBVIOUS. DURING THIS INSP, THE INBD FLAP BALLSCREW ACTUATOR PN 8SC0121 ON THIS LT SIDE OTBD FLAP WAS ALSO REPLACED DUE TO EXCESSIVE PLAY AT THE ACTUATOR T/O JACKSCREW ATTACH POINT. UNABLE TO ASCERTAIN IF THE FLAP OVERSPEED WAS A CONTRIBUTING FACTOR OR IF IT WAS NORMAL WEAR OVER SERVICE LIFE. THE ACTUATOR AND FLAP T/E WERE REPLACED. FLAP SYS CHECKED SERVICEABLE AND ACFT RETURNED TO SERVICE.