A350风挡有三层，内侧两层外侧一层，内侧是影响结构的。但如果破裂的是内侧靠中间那一层，程序中国提供的用手指或笔轻触的方法并不能判断出，所以存在风险。空客考虑后续修改。具体参考 TechRequest 原文：
Q17: [ABN] MISC CKPT WINDOW CRACKED
Refer to DSC-56-10 Cockpit Windshields and Windows
If one of the internal layers is cracked, the pen or fingernail won't feel any unsmooth. So how can crew determine if the cracked layer is internal one or external layer? Is it the same with it in A320 FCTM:
A17:
We would like inform you that the procedure called MISC CKPT WINDOW CRACKED is the only applicable mean to troubleshoot such a damage. As such, the cracked windows ‘patterns provided in the additional visual clues paragraph of the A320 FCTM is not applicable to the A350.
Nevertheless, the check with the fingernail /pen is alike.
The check is based on the inner internal layer status:
- If affected [YES], at least one structural ply is broken with no possible assessment on the middle internal layer. As a consequence, the flight crew must reduce the differential pressure.
- If not affected [NO], it means that at least one structural layer is safe.
We agree that the note of the NO condition is misleading as the flight crew cannot confirm that the middle internal layer is not affected as well. Consequently, Airbus will consider to review this information.
