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Small Cracks In Windows

Sidewinder From , joined Dec 1969, posts, RR:
Posted (7 years 9 months 3 weeks 6 days 13 hours ago) and read 1875 times:

I just flew on an Airtran 717 and noticed very small cracks in the windows. I have seen scratches on airliner windows but never small cracks. Is this normal? I looked at the windows in the rows around me and all had the same cracks. Also, what are the little holes for? I am guessing that they keep the window from fogging up.

13 replies: All unread, jump to last

Scott0305 From United Kingdom, joined May 2005, 196 posts, RR: 0
Reply 1, posted (7 years 9 months 3 weeks 6 days 12 hours ago) and read 1852 times:

You sure the cracks weren't ice? Not saying you can't tell the difference between cracks and ice but sometimes it can be deceptive. Pretty sure the holes are to stop condensation forming between the panes.

Sidewinder From , joined Dec 1969, posts, RR:
Reply 2, posted (7 years 9 months 3 weeks 6 days 12 hours ago) and read 1844 times:

I thought the same thing at first....but we were on the ground in ATL in July. They reminded me of a piece of plastic that has been stressed. very thin spider cracks.

EMBQA From United States of America, joined Oct 2003, 9286 posts, RR: 13
Reply 3, posted (7 years 9 months 3 weeks 6 days 12 hours ago) and read 1844 times:

Also, it could be one of three windows. Most commercial aircraft have an outer window, a mid-window and a thin inner pain. Which one was it...? The only 'load' bearing is the outer window.

"It's not the size of the dog in the fight, but the size of the fight in the dog"

Sidewinder From , joined Dec 1969, posts, RR:
Reply 4, posted (7 years 9 months 3 weeks 6 days 12 hours ago) and read 1841 times:

Quoting EMBQA (Reply 3):
Also, it could be one of three windows. Most commercial aircraft have an outer window, a mid-window and a thin inner pain. Which one was it...? The only 'load' bearing is the outer window.

It must have been either the middle or outer. The inner you could look through at an angle to the gap in between and tell that it was ok.

MD11Engineer From Germany, joined Oct 2003, 13337 posts, RR: 64
Reply 5, posted (7 years 9 months 3 weeks 6 days 11 hours ago) and read 1823 times:

Both window layers can each carry the whole pressure load. The inner pane is just there to protect the two window layers from scratches.

Jan

SlamClick From United States of America, joined Nov 2003, 10062 posts, RR: 71
Reply 6, posted (7 years 9 months 3 weeks 6 days 10 hours ago) and read 1808 times:

Sounds like maybe "crazing" on a plexiglas layer. Pretty common in older airframes.

Happiness is not seeing another trite Ste. Maarten photo all week long.

Efohdee From United States of America, joined Oct 2004, 214 posts, RR: 0
Reply 7, posted (7 years 9 months 3 weeks 6 days 10 hours ago) and read 1785 times:

Last time I flew was on a Continental 757, my window had really bad crazing, I couldn't get any decent photos. It wasn't the inner window. Sad

Troubleshooter From Germany, joined Feb 2005, 423 posts, RR: 5
Reply 8, posted (7 years 9 months 3 weeks 6 days 8 hours ago) and read 1751 times:

From the ERJ AMM 56-20-01-6:

Quote:
Do a detailed inspection on all passenger cabin windows for crazing.
Crazing is permitted when limited to an area not larger than 150 cm2 (23 in2) on the acrylic outer ply.
NOTE: No crazing is permitted on the other plies.

The hole in the inner pane is necessary to send the pressure to the puter pane and to prevent moisture build up between both panes. As others stated above one pane can carry the full pressure loads in case of failure.

This job sucks!!! I love this job!!!

HAWK21M From India, joined Jan 2001, 31201 posts, RR: 58
Reply 9, posted (7 years 9 months 3 weeks 6 days 5 hours ago) and read 1706 times:

The Hole in the Inner pane prevents moisture buildup between Inner & Outer pane & if a dust mark forms on the Pane near the hole it indicates Seal leakage.

Are you refering to Cracks or Crazing.
regds
MEL

Think of the brighter side!

Scott0305 From United Kingdom, joined May 2005, 196 posts, RR: 0
Reply 10, posted (7 years 9 months 3 weeks 5 days 22 hours ago) and read 1653 times:

I'm not familiar with the term crazing. Does this refer to scratches on the pain? I have been on board older frames where the windows have seemed to be awfully scratched up.

Sidewinder - ATL in July, eh? That would have to be some serious climate change for ice to form. My bad.

HAWK21M From India, joined Jan 2001, 31201 posts, RR: 58
Reply 11, posted (7 years 9 months 3 weeks 5 days 21 hours ago) and read 1632 times:

Crazed Window
Fine cracks resulting from shrinkage on the surface.Crazing is defined as fine and random cracking extending only through the surface. It can appear along or perpendicular to the length, in polygonal shapes or as random "map cracking." Crazing is due to differential contraction between the surface and interior sections
regds
MEL

Think of the brighter side!

Sidewinder From , joined Dec 1969, posts, RR:
Reply 12, posted (7 years 9 months 3 weeks 5 days 20 hours ago) and read 1609 times:

Quoting HAWK21M (Reply 9):
The Hole in the Inner pane prevents moisture buildup between Inner & Outer pane & if a dust mark forms on the Pane near the hole it indicates Seal leakage.

I also noticed dust at the holes entrance. Correct me if i am wrong but these ac are only a couple years old. Sounds like a poor design.
If my window would have been the only one I would have brought it to the attention of the fa.