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fra
21st May 2016, 13:19
Many incidents and accidents in the past and recent history of the Aviation have been recorded as attributable to a short circuit of the heating wires of the windshield that in some situations has led to a smoke and fire spread out in the cockpit.
Here we have an example:
http://www.dailymail.co.uk/news/article-1290535/How-faulty-heater-caused-windshield-cockpit-passenger-jet-shatter--thousands-feet-Atlantic.html

Have you ever experienced or had time to discuss about this case in your career?

It would be interesting for me to share your opinions about this matter.
Thanks for your availability.

Derfred
22nd May 2016, 02:18
I've had a windshield outer pane shatter and this was followed by window heat arcing. I have always believed it was the broken windshield that caused the arcing, not the other way around. Solution: simple - window heat OFF.

Uplinker
22nd May 2016, 02:34
We were once hit by a micrometeorite which shattered the outer pane and caused arcing of the heating layer. We actioned the QRH, pulled the appropriate heating breakers, and returned to base.

clark y
22nd May 2016, 02:37
https://www.atsb.gov.au/media/2500357/ao-2009-027%20final.pdf

Have a read of the above link for an A330 event.

piratepete
22nd May 2016, 02:48
I have had 7 failures of some kind or another of cockpit forward windows.I dont know if this typical or not after 18000 hours flying jets, but never was the flight in danger, we just continued to destination and even flew another sector in the same condition iaw the MEL until Boeing changed the MEL a few years ago to the same as Airbus.
Sometimes the thing goes BANG with shattering other times arcing then cracking, but otherwise not a big deal AS LONG AS ITS NOT THE STRUCTURAL INNER LAYER..........

ACMS
22nd May 2016, 08:25
Don't know about you blokes but I'll follow the QRH and FCOM.....

NSEU
23rd May 2016, 00:59
I've had a windshield outer pane shatter and this was followed by window heat arcing. I have always believed it was the broken windshield that caused the arcing, not the other way around. Solution: simple - window heat OFF.

On many aircraft types, window heat OFF only turns off the heat to the front windows, so pulling circuit breakers will be required for the side windows.

kit344
23rd May 2016, 12:59
Is the WHC a Window Heat Computer or should it be more accurately described as a Window Heat Controller.

I'm fairly old-school (former RAF Radar Tech.) with most of my training on both Digital and Analogue systems in the 1980's. Some of the gear I worked on dated back to 1950's, Canberra, Victor etc. as well as Jaguar and Tornado digital avioinics.

To me a Computer would usually provide data outputs for display on Cockpit systems, or provide outputs to drive Flight Controls or Engine functions. A Window Controller would provide simple functions like controlling the current to heating systems in a Window or group of windows, and could be Controlling several Amps, but is it really a Computer ?

Evanelpus
23rd May 2016, 15:19
How many more times do we have to tell you people DON'T BELIEVE WHAT YOU READ IN THE DAILY MAIL

Now, is that clear enough for you?

goeasy
24th May 2016, 04:52
Yes, the Egyptair incident has nothing to do with windscreens. Side windows are different architecture, and heated to a much lower level.

The ACARS warnings may well just mean the WHC dropped its output for whatever reason, but all actual window heat was operating normally.....

ad-astra
24th May 2016, 19:51
Follow the NNC.
From my experience its common but no biggie.
http://i865.photobucket.com/albums/ab211/timsmarina/100-0063_IMG.jpg (http://s865.photobucket.com/user/timsmarina/media/100-0063_IMG.jpg.html)

Mansfield
2nd Jun 2016, 11:26
We need to separate the cracked windshield discussion from the windshield heat failure discussion. They are only marginally related. Never mind the Daily Mail...:ugh:...a thorough review of FAA Service Difficulty Reports will reveal that windshield heat system arcing and occasional smoke and flame are not unheard of, and in fact occur with enough regularity to catch your eye when scanning the data. That said, the fact that this appears primarily in the SDRs suggests that in almost all cases, it is easily managed.

Perhaps this case will be different.

Piltdown Man
2nd Jun 2016, 21:56
Over the years I've had seven windows shatter on me. To date, every one was preceded by a window heat fault. Then, as you either action the checklist and turn off the window heat or the heat is turned off by the aircraft (tripped C/B, controller function etc.) the window shatters. So far, I've only ever had an outside layer shatter. But what a bang it makes when it lets go. Because the outer layer none of them have had much effect on any of my flights. A failed inner layer would have had more of an effect but even then, a safe outcome should be assured.

PM

Ngineer
2nd Jun 2016, 22:15
Have had many cracked/shattered/delaminated windows over 30+ years but never ever had or experienced a short circuit causing arcing or fire damage in a window or windshield. And I have seen many aircraft, and many different types on a daily basis.


Just saying it would be a very rare occurrence to have a fire/arcing.

A and C
11th Jun 2016, 12:56
IMO the window issue was a result of another much greater failure in the electrical system and not the cause of it.

TURIN
12th Jun 2016, 13:15
How to manage a windshield arcing? Probable cause of Egyptair accident?

Where did this come from? Based on what evidence.