Narrative:

June 2009. B747-400 aircraft at international station. Left L-1 windshield delamination. During my preflight; I noticed three problems with the cockpit windows: 1. Four inches of window (left) L-2 exterior bedding compound was delaminated at the lower right corner of the window 2. The captain's windshield (L-1) had a 14 inch delamination on the bottom edge of the window; measuring approximately 14 inches by 1 inch. This delamination was cloudy (opaque) in appearance. 3. Both upper corners of window L-1 appeared to have delaminations with moisture ingress; each measuring approximately 1 inch by .5 inch. Both delaminations were cloudy and had ragged edges. We advised maintenance control that the delaminations were cloudy. According to the maintenance manual; MM 56-11-00; the delamination is seen as a shiny; flat bubble. These delaminations were opaque and the corner areas had ragged edges. 4. Further investigation by the station mechanic revealed that the entire perimeter of L-1 was delaminated except for about a 16 inch section on the bottom edge of the window. We notified maintenance control via dispatch and entered the items into maintenance computer history. There was some question about the water ingress issue; which would require a window change in accordance with the 747-400 maintenance manual 56-11-00 (4)(a)(b).station maintenance took pictures of the affected areas and sent them to maintenance control for review. Maintenance controller sent us an ACARS message stating; I concur with window replacement required. Since no parts; required equipment; and adequate personnel were available at ZZZ for the window change; operations decided to assign us to perform a type ii maintenance ferry to the international maintenance station. I discussed this with the first officer. We decided that we would be agreeable to perform the ferry flight if the L-1 window heat were to be disabled.this decision was based upon the following: 1. Our only safety concern was potential arcing and possible failure of window L-1. 2. No arcing would be possible if the window heat was disabled. We contacted dispatch to flight plan the ferry. However; the dispatcher advised us that flight into known; or forecast icing conditions was prohibited with this deferral and; therefore; he could not dispatch the flight to the international maintenance station; because of thunderstorms in the terminal area. We (dispatch; pilots; maintenance control) collectively explored all possible strategies to legally and safely ferry the aircraft to the international maintenance station; but could not come up with a suitable plan. I also had a telephone conversation with the chief pilots office and they concurred.a subsequent review of the B747-400's maintenance history revealed that maintenance inspected the cockpit windows june 2009; and found all windows to be within limits.it seems unconceivable that window L-1 could have developed a nearly total circumferential delamination with moisture ingress in two corners in just 3 days; but I guess anything is possible. I have written recent reports about the lack of adequate maintenance. The flight subsequently was canceled.

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Original NASA ASRS Text

Title: During preflight at an international station; a B747-400 Captain noticed three problems with the L-1 and L2 cockpit windows involving delaminations; cloudy opaque sections and moisture ingress indications. Captain also questioned how window L-1 could have developed a nearly total circumferential delamination; with moisture ingress in two corners; in just three days; since the last maintenance check.

Narrative: June 2009. B747-400 aircraft at International station. Left L-1 WINDSHIELD DELAMINATION. During my preflight; I noticed three problems with the cockpit windows: 1. Four inches of window (left) L-2 exterior bedding compound was delaminated at the lower right corner of the window 2. The Captain's windshield (L-1) had a 14 inch delamination on the bottom edge of the window; measuring approximately 14 inches by 1 inch. This delamination was cloudy (opaque) in appearance. 3. Both upper corners of window L-1 appeared to have delaminations with moisture ingress; each measuring approximately 1 inch by .5 inch. Both delaminations were cloudy and had ragged edges. We advised Maintenance Control that the delaminations were cloudy. According to the Maintenance Manual; MM 56-11-00; the delamination is seen as a shiny; flat bubble. These delaminations were opaque and the corner areas had ragged edges. 4. Further investigation by the Station Mechanic revealed that the entire perimeter of L-1 was delaminated except for about a 16 inch section on the bottom edge of the window. We notified Maintenance Control via Dispatch and entered the items into Maintenance computer history. There was some question about the water ingress issue; which would require a window change in accordance with the 747-400 Maintenance Manual 56-11-00 (4)(a)(b).Station maintenance took pictures of the affected areas and sent them to Maintenance Control for review. Maintenance Controller sent us an ACARS message stating; I concur with window replacement required. Since no parts; required equipment; and adequate personnel were available at ZZZ for the window change; Operations decided to assign us to perform a Type II Maintenance Ferry to the international maintenance station. I discussed this with the First Officer. We decided that we would be agreeable to perform the Ferry flight if the L-1 window heat were to be disabled.This decision was based upon the following: 1. Our only safety concern was potential arcing and possible failure of window L-1. 2. No arcing would be possible if the window heat was disabled. We contacted Dispatch to flight plan the ferry. However; the Dispatcher advised us that flight into known; or forecast icing conditions was prohibited with this deferral and; therefore; he could not dispatch the flight to the international maintenance station; because of thunderstorms in the terminal area. We (Dispatch; Pilots; Maintenance Control) collectively explored all possible strategies to legally and safely ferry the aircraft to the international maintenance station; but could not come up with a suitable plan. I also had a telephone conversation with the chief pilots office and they concurred.A subsequent review of the B747-400's Maintenance history revealed that Maintenance inspected the cockpit windows June 2009; and found all windows to be within limits.It seems unconceivable that window L-1 could have developed a nearly total circumferential delamination with moisture ingress in two corners in just 3 days; but I guess anything is possible. I have written recent reports about the lack of adequate maintenance. The flight subsequently was canceled.

Data retrieved from NASA's ASRS site as of April 2012 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.