Narrative:

During preflight; I noticed that my forward windshield L1 had what appeared to be the following defects: 1. Interlayer cracking 2. Heat crackling 3. Delamination 4. Moisture ingress 5. A 1 inch scratch on the inner pane 6 inches in from the left edge which was deep enough to catch a fingernail 6. Dark discoloration along the bus bar. We called maintenance but at this point; I was mostly concerned with the scratch because I know that it can be a structural issue and a no-go item. I am very concerned about 747-400 cockpit windows after the incident on another B747 which suffered decompression due to right hand flight deck window failure. The mechanic came to the cockpit and immediately dismissed the crack; stating it was ok. Having some knowledge of MM 56-11-00; I asked him to show me the limitations; and he went off to get them. During his absence; I called maintenance control through dispatch via satcom to discuss the window. The maintenance controller; also immediately dismissed the scratch. I asked him to read me the limits. At this point; maintenance control could see that I was not going to be a pushover; and began deferring the decision to local maintenance. After awhile; the local mechanic returned to the cockpit with 56-11-00; which indicates that any scratch that catches a fingernail is deep enough to warrant a measurement with special micrometer. A scratch on a triplex window is a no-go item. A scratch on a ppg window is acceptable. The mechanic did not use any tools except a flashlight in his assessment of the window. The mechanic and maintenance control could not determine which type of window was installed because it was unlabeled. Apparently; maintenance control also could not determine the type by looking in the maintenance records. It took about 30 minutes before the mechanic determined that the window was a ppg window based upon his looking at the panes with his flashlight. The mechanic also dismissed the other defects; which affected the entire periphery of the L1 windshield. The maintenance release stated the following: ok window 1L lh side lower has scratch. 1/4 inch .002 inch depth. Per. MM56-11-00. I have a few concerns: 1. The scratch was 1 inch long. I measured it with a ruler. The mechanic never used any tool to determine its length or its depth. How; then; did he determine its length and depth? Can he really eyeball .002 inches? 2. What about the other defects which were clearly visible? At the very least; the window should have been noted for future replacement. 3. The window showed at least three no-go defects: moisture ingress; discoloration at the bus bar; and signs of arcing evidenced by dark brown spots. There is no mention of these in the action. 4. Had we not pressed the issue about the scratch; both maintenance control and maintenance would have dismissed it without performing the required MM determination of airworthiness. 5. It appears that maintenance is not adequately inspecting the B-747-400 windows on a timely basis to discover serious defects. This is the second defective window in a 4-flight trip. I would estimate; based on my recent experience; that up to 25% of the 400 fleet is flying today with cockpit windows having reportable defects. Yet; no action is being taken unless pilots write them up. 6. It is apparent that both maintenance control and line maintenance are not adequately educated about the requirements contained in 56-11-00. This incident is a clear case-in-point. 7. Pilots are required to preflight the windows but receive almost no training on reportable window defects. 8. I felt very intimidated when I was recently put on no-fly status for a short time as a result of my safety advocacy and my writing up a cockpit window defect in accordance with the fom and the far. This report is difficult for me to write under the circumstances; but I feel that it is my moral; ethical; and legal obligation to do so in the interest of air safety. We had an FAA maintenance inspector in the cockpit giving us a line check. He stated that he thought we had done the right thing in reporting the defects.

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Original NASA ASRS Text

Title: B747 Captain reports lack of proper maintenance action to replace damaged cockpit windows which he has encountered in his company's fleet.

Narrative: During preflight; I noticed that my forward windshield L1 had what appeared to be the following defects: 1. Interlayer cracking 2. Heat crackling 3. Delamination 4. Moisture ingress 5. A 1 inch scratch on the inner pane 6 inches in from the left edge which was deep enough to catch a fingernail 6. Dark discoloration along the bus bar. We called maintenance but at this point; I was mostly concerned with the scratch because I know that it can be a structural issue and a no-go item. I am very concerned about 747-400 cockpit windows after the incident on another B747 which suffered decompression due to right hand flight deck window failure. The mechanic came to the cockpit and immediately dismissed the crack; stating it was ok. Having some knowledge of MM 56-11-00; I asked him to show me the limitations; and he went off to get them. During his absence; I called Maintenance Control through Dispatch via SATCOM to discuss the window. The Maintenance controller; also immediately dismissed the scratch. I asked him to read me the limits. At this point; Maintenance Control could see that I was not going to be a pushover; and began deferring the decision to local maintenance. After awhile; the local mechanic returned to the cockpit with 56-11-00; which indicates that any scratch that catches a fingernail is deep enough to warrant a measurement with special micrometer. A scratch on a Triplex window is a no-go item. A scratch on a PPG window is acceptable. The mechanic did not use any tools except a flashlight in his assessment of the window. The mechanic and Maintenance Control could not determine which type of window was installed because it was unlabeled. Apparently; Maintenance Control also could not determine the type by looking in the maintenance records. It took about 30 minutes before the mechanic determined that the window was a PPG window based upon his looking at the panes with his flashlight. The mechanic also dismissed the other defects; which affected the entire periphery of the L1 windshield. The maintenance release stated the following: OK WINDOW 1L LH SIDE LOWER HAS SCRATCH. 1/4 INCH .002 INCH DEPTH. PER. MM56-11-00. I have a few concerns: 1. The scratch was 1 inch long. I measured it with a ruler. The mechanic NEVER used any tool to determine its length or its depth. How; then; did he determine its length and depth? Can he really eyeball .002 inches? 2. What about the other defects which were clearly visible? At the very least; the window should have been noted for future replacement. 3. The window showed at least three no-go defects: moisture ingress; discoloration at the bus bar; and signs of arcing evidenced by dark brown spots. There is no mention of these in the ACTION. 4. Had we not pressed the issue about the scratch; both Maintenance Control and maintenance would have dismissed it without performing the required MM determination of airworthiness. 5. It appears that maintenance is not adequately inspecting the B-747-400 windows on a timely basis to discover serious defects. This is the second defective window in a 4-flight trip. I would estimate; based on my recent experience; that up to 25% of the 400 fleet is flying today with cockpit windows having reportable defects. Yet; no action is being taken unless pilots write them up. 6. It is apparent that both Maintenance Control and line maintenance are not adequately educated about the requirements contained in 56-11-00. This incident is a clear case-in-point. 7. Pilots are required to preflight the windows but receive almost no training on reportable window defects. 8. I felt very intimidated when I was recently put on no-fly status for a short time as a result of my safety advocacy and my writing up a cockpit window defect in accordance with the FOM and the FAR. This report is difficult for me to write under the circumstances; but I feel that it is my moral; ethical; and legal obligation to do so in the interest of air safety. We had an FAA maintenance inspector in the cockpit giving us a line check. He stated that he thought we had done the right thing in reporting the defects.

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.