Examination Details
The damaged left side windshield (part number NP139321-17, serial number 18338H6714) from aircraft N561NN was removed and shipped to PPG Aerospace in Huntsville, Alabama. PPG examined the window in November 2020. The windshield serial number indicated it was a new unit completed in December 2018.
Windshield History
The subject windshield was installed on N561NN and had accumulated 3,238.53 flight hours and 2,870 flight cycles. PPG Aerospace completed manufacture of the window in December 2018.
Teardown Findings
A teardown of the unit identified the failure origin underneath the power terminal block at the power braid A location. Removal of the terminal block and sealant revealed an arcing hot spot where the failure occurred at power braid wire position A. There was no visible solder at the connection point of braid wire A. The braid wire solder connection point at position B was still intact.