Incident Overview
On August 13, 2015, a Saab 340A aircraft experienced a crack in the left front windshield during cruise at flight level 150. The crew assessed that the crack was confined to the outer layer of the windshield and that no cabin decompression had occurred. Due to the short distance remaining to the destination airport, the flight was continued as planned. After landing, the aircraft was handed over to maintenance personnel for inspection.
Details
Examination of the windshield confirmed that the crack affected only the outer heating layer. The inner acrylic layers, which bear structural loads and are significantly thicker than the glass layer, remained intact. According to the scheduled maintenance program, cockpit windshields are not classified as "hard time" or "life-limited parts" and therefore are not subject to periodic replacement. Instead, they undergo routine checks for delamination between layers.
Findings
The investigation found no evidence of decompression or any immediate safety hazard during the flight. The crack did not compromise the structural integrity of the windshield. The crew's decision to continue to the destination was deemed appropriate given the circumstances.
Probable Cause
The probable cause was most likely wear or a short circuit of the windshield heating element, which led to cracking of the outer protective glass layer.
Preventive Actions
As preventive measures, the operator notified both flight and maintenance personnel about the incident. The case was also scheduled for discussion during the next periodic training session. No safety recommendations were issued by the investigation committee.