Windscreen Cracks

[underfire]

I personally have had 2 flights in the last 3 weeks where the ac was replaced due to windshield cracks, both 737-800's. My son was on another flight from SFO to SEA in the same time period that was replaced, due to windscreen crack, again 737-800. (All of these flights were on the West Coast of the US, all with the same airline)

In the news, there have been many reports lately of flights with cracked windscreens, quite a few with the 787.

Aside from my own experience, this seems to be quite unusual.

Is this actually unusual, or is the press just focused on the issue?

[RVF750]

Statistics.


There are more 737-800 flying out there than anything else. Windscreens can age and weather conditions such as cold snaps can also influence reliability.


The screens are multi layered with glass and Perspex sandwich construction in aircraft screens. Cracks happen. The more there are up there, the more it will happen to a particular type.


As there's a 737 taking off somewhere every minute on average, you've got 1,500 flights a day to go on.....

[underfire]

TD,

There are not many 787's out there, with many of them having crack issues, another today...those ac are not very old.

In reality, I have not heard of many instances with cracked windscreens, with any other aircraft variant. There are just as many A320s out there as 737-800...
there are many more 737NG variants than the 800's combined, yet there are no news reports of cracked windscreens on anything but the 7378 and 787.

What about the 787? There have been many news reports of that ac with cracked windscreens, yet how many are in operation?

Again, is this an issue in general, or just Boeing news?

[DaveReidUK]

There are just as many A320s out there as 737-800... there are many more 737NG variants than the 800's combined, yet there are no news reports of cracked windscreens on anything but the 7378 and 787.

Plenty of Airbus cracked windscreens documented here:

http://www.caa.co.uk/docs/1357/F0001519ReplyLetter.pdf

[underfire]

EDIT: Thanks Dave, didnt see you post before commenting.

Perhaps the CAA UK should ID ac other than 737, as there are many variants. (the report noted cracks in 'eyebrow' windows in the 737...well damn..how old is that, yet still 737)

The windshield of a newer Air India Boeing 787 cracked on a flight from Mumbai to Delhi on Saturday.

It’s the second time in just over a month that a crack has been reported.

Air India says the windshield cracked while landing in Delhi, but there was no risk to the aircraft.

A Boeing team is already in India fixing a different software issue.

[No Fly Zone]

738 WS Cracks?

I have to go with the random odds. Most WSs are pretty close to the same and there just happens to be a who lot of 738s making a lot of flights, thus getting inspected a lot. When a crack appears in flight, they put down and R&R the WS. There are so many 738s flying around that finding a replacement WS on short notice is usually not a problem. As I recall, the R&R procedure takes about 60-90 minutes and is a non-event for for the tech folks. That said, I'm not a techie and maybe I'm blowing smoke. All of that said, random cracks in a layer are FAR different from a full thickness fracture or complete blow out. Those events are exceedingly rare.

[putz]

A cracked windshield on a 737 is quite rare. Most likely reason for a L1/R1 window change is fine scratches in the windshield which obstructs vision, caused by the windshield wipers. Another less common reason is electrical arcing within the windshield.

As I recall, the R&R procedure takes about 60-90 minutes and is a non-event for for the tech folks.

Not on the 737, more like 4-6 hours.

[Aluminium shuffler]

I have seen a few partially delaminated 73 screens, all within limits and usually no.4 or 5, but never a cracked on in 12,000 of flying them. I don't know anyone who has, either. They will occur from time to time, but I suspect it's be due mostly to impact damage, not a manufacturing fault.