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A320 aircon ,.mist on take off till around 7,000ft

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A320 aircon ,.mist on take off till around 7,000ft

Old 30th Aug 2019, 19:47
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A320 aircon ,.mist on take off till around 7,000ft

Venice BA..31/20 temps..Pouring up from the window fairing into the roof fairing..possible oil smell but at my age I cant even smell myself.
Not uncommon in the tropics but never seen it for so long .
Stopped RHS around 4,000ft.
normal?
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Old 30th Aug 2019, 19:57
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Originally Posted by blind pew View Post
Venice BA..31/20 temps..Pouring up from the window fairing into the roof fairing..possible oil smell but at my age I cant even smell myself.
Not uncommon in the tropics but never seen it for so long .
Stopped RHS around 4,000ft.
normal?
If You had loads of moisture that is very normal during summer time even in Europe nowadays. The other day we were sitting on the tarmac with 36 degrees and 80% humidity. The RVR inside the cabin was maybe 20 cm. We landed in Delhi 8 hours later only to find the same ground temperature and humidity. Guess they call it global warming or so.
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Old 30th Aug 2019, 20:03
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Thanks in my day the packs were off for takeoff..

Havent seen it 737s and pax them 20 times a year.
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Old 30th Aug 2019, 21:56
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It happens a lot on the 320. Donít know exactly why, but seems to be peculiar to the type. Didnít see much of it on other a/c
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Old 31st Aug 2019, 07:00
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Thanks..although I was supposed to start a course on the 319/20 before I lost my license I’ve only flown on orange and green liveried aircraft before and never seen a hint of it. Obviously somfink to do with smoke and mirrors..apologies.
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Old 31st Aug 2019, 07:29
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Misting like that is perfectly normal and occurs when the duct temperatures are turned down to minimum for rapid cooling during high humidity. I avoid it by keeping the duct temperature above minimum setting, but that reduces the rate at which the cabin cools. In addition, our cabin crew make a PA to reassure infrequent Airbus passengers that the misting is normal and will clear when the cabin reaches a comfortable temperature.
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Old 31st Aug 2019, 08:15
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Thanks but 31/20 ain’t actually high humidity..the new girl I informed of the long duration hadn’t got a clue and judging by the mixing a Yorkshire pudding on the side stick by the skipper after leaving the hold he didn’t have the wherewithal to minimise the phenomenon.
Totally different to the way out with a personal mini hero of mine up front (small world of glider aeros and adventurous mountain fliers).
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Old 31st Aug 2019, 08:47
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31/20 is a RH of 52.09%, that’s pretty high to me. “It is what it is”, as the kids say nowadays.
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Old 31st Aug 2019, 14:22
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Thanks but 31/20 ain’t actually high humidity..the new girl I informed of the long duration hadn’t got a clue and judging by the mixing a Yorkshire pudding on the side stick by the skipper after leaving the hold he didn’t have the wherewithal to minimise the phenomenon.
Wow.

although I was supposed to start a course on the 319/20 before I lost my license
Sounds like a lucky escape for the rest of us. Misting is perfectly normal on the A320 series but can be exacerbated in my experience if the flight deck and cabin target temperatures are set a long way apart. Airbus have been fiddling with the air conditioning architecture off and on for years.
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Old 1st Sep 2019, 00:03
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Not uncommon, the worse I've seen personally was on a Shorts 360 at Miami during start/taxi, as bad as the video. Our air force had a new on type pilot eject from a Sabre because mist was coming from the ducts and he thought it was smoke from a fire.

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Old 1st Sep 2019, 00:10
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Originally Posted by blind pew View Post
Thanks but 31/20 ainít actually high humidity..the new girl I informed of the long duration hadnít got a clue and judging by the mixing a Yorkshire pudding on the side stick by the skipper after leaving the hold he didnít have the wherewithal to minimise the phenomenon.
Totally different to the way out with a personal mini hero of mine up front (small world of glider aeros and adventurous mountain fliers).
So a dew point of 20 degrees. What do you reckon the pack outlet temp might have been? Less than 20 perhaps?
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Old 1st Sep 2019, 00:26
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I have had this so thick in the tropics that you can't see row one from the Flightdeck. It is quite normal, I usually just make a quick PA to inform the passengers that the mist is just due to the high OAT. Never had any issues with it, normally stops below 10k.
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Old 1st Sep 2019, 02:05
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The A320 pack sprays condensed water from the water extractor into the pack ram air inlet to help cooling of air conditioned air. You can see this if you peer into the pack ram air inlets during the walk around. Is this a contributory factor?

Like a few have mentioned, seems like this excessive misting only happens on the A320 series.
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Old 1st Sep 2019, 04:13
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Its normal.
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Old 1st Sep 2019, 06:45
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Had it in a dark blue Volvo 850 with a newly re-gassed air conditioning on a particularly hot day.
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Old 1st Sep 2019, 07:53
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Dream 747

Thanks that explains it. Thought it must be different to the kites I've driven.
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Old 1st Sep 2019, 08:12
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I’ve had significant misting in BAe146 family aircraft (no, not oil fumes you wags!)
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Old 22nd Sep 2019, 20:25
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Cabin crew here...

This is very common on the A320 series during the summer months, particularly when the OAT and/or relative humidity is high. Our operator has a PRAM that we can use to reassure any concerns during boarding.

As for the 737, I seem to recall that they have a water separator downstream of the PACKs,



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Old 23rd Sep 2019, 10:01
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As others have said, simply pack output below the dew point, its physics Jim. Only seen it significantly once on a 717 waiting on the tarmac for a thunderstorm to pass.
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Old 24th Sep 2019, 09:59
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Originally Posted by dream747 View Post
The A320 pack sprays condensed water from the water extractor into the pack ram air inlet to help cooling of air conditioned air. You can see this if you peer into the pack ram air inlets during the walk around. Is this a contributory factor?
.
No, it isn't. Water sparayed into the pack cooling airflow is "outside" of internal air conditon circuit, only helps with heat transfer on heat exchangers.
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