Kellie From Australia, joined Jun 2006, 3 posts, RR: 0 Posted (3 years 1 month 1 week 5 days 9 hours ago) and read 21857 times:
On an A330-300 out of Singapore Airport one humid warm evening 3 weeks ago, as we climbed out of Singapore, there was a freaky sound that lasted for 10 mins, of what seemed like hundreds of ice cube sized pieces of ice rolling from the front of the aircraft to the back, over and over again, between the cabin ceiling and the outer skin of the plane. It was loud and consistent and two passengers ignored the seatbelt sign and alerted the flight crew who said it was the air-conditioning. The passengers were all alarmed and worried until the noise ceased. What was going on? There were no clouds or rain at the time, it was a warm clear evening. Any ideas? Has anyone come across this before?
BD338 From United States of America, joined Jul 2010, 658 posts, RR: 0 Reply 1, posted (3 years 1 month 1 week 5 days 9 hours ago) and read 21790 times:
Can't say I've ever come across that noise on any aircraft, rule of thumb if the flight attendants aren't worried by it I tend not to worry. They fly every day and know what sounds and looks right/wrong. A330 are usually some of the quieter aircraft on take-off I find.
I did once get a good shower from the AC condensation in a QF 747 on take off from Brisbane a couple of years ago, water just poured out of the panels under the overhead lockers. A real treat for the start of a 13 hour flight
It's actually quite common from my experience. I've often heard particles of ice clunking their way down the air-conditioning ducts whilst I was fixing stuff in the cabin. The fact that it was so humid supports the notion that what you heard was indeed ice. It never ceases to amaze me how effective the air-conditioning systems are on a commercial airliners. To think they manage to cool air down so much without using any sort of refrigerant!
You often also see thick, white clouds of condensation (not ice) when you run things such as air driven pumps and starter motors. The same basic principle is at play here, the sudden expansion and cooling of the air causes water vapour to condense (and possibly form ice).
[Edited 2010-11-09 19:44:42]
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pugsley From Australia, joined Jan 2010, 161 posts, RR: 0 Reply 3, posted (3 years 1 month 1 week 5 days 8 hours ago) and read 21486 times:
Quoting BD338 (Reply 1): A real treat for the start of a 13 hour flight
Was it actuallt from the Air Con? I regulary need to mop up mess/water coming from the overhead lockers, however it is always liquid coming from a drink/water bottle that someone has left in their bag in the overhead locker. When the pressure inside the aircraft changes, if the lid of the bottle does not seal properly or the bottle is lying on it side, they always leak all over the pax.
Quoting jetmech (Reply 2): It's actually quite common from my experience.
While i've never heard it last for 10 min, this is a common occurance on A330's and usually happens once or twice once the aircraft has pusshed back and is during the climb phase of flight.
type-rated From United States of America, joined Sep 1999, 4731 posts, RR: 20 Reply 6, posted (3 years 1 month 1 week 5 days 7 hours ago) and read 21034 times:
I once took an AA F100 IAH-ORD early in the am after the aircraft sat overnight at IAH in the warm very humid air. All the windows were covered in moisture until take off. About 1/2 way on the trip to ORD, the same thing you described happened. It was very loud. It sounded like a bowling ball was being rolled down the top of the fuselage from the front to the back.
The F/A's even said they haven't heard this noise before. A short time later the captain made a PA explaining what all the racket was. But it sounded like the roof was going to let go!
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AA737-823 From United States of America, joined Mar 2000, 5547 posts, RR: 11 Reply 9, posted (3 years 1 month 1 week 5 days 5 hours ago) and read 20570 times:
This is common only in particularly humid environments. The moisture will sometimes form ice- we have systems in the AC Packs that remove moisture, but as with all machines, they are NOT 100% efficient at their task.
So, you end up with some moisture freezing up, and then being broken loose by vibration, or melting as the pack rapidly increases its output temperature due to the quickly dropping ambient temp outside.
AA737-823 From United States of America, joined Mar 2000, 5547 posts, RR: 11 Reply 11, posted (3 years 1 month 1 week 5 days 1 hour ago) and read 19833 times:
Quoting bill142 (Reply 10): Seems to be an Airbus issue. On a recent A380 flight to LHR people were complaining of being snowed on, but were advised by the crew that it happens and that it was an 'Airbus thing'
If you've flown AA through DFW, chance are you were on an MD-80, and in the humid summers, they steam, fog, and sputter out of the vents while at the gate even.
I've been in 737s that rained on me.
And, as I pointed out above, Fokkers were well-known for blowing ice chunks down the air duct above the ceiling.
BD338 From United States of America, joined Jul 2010, 658 posts, RR: 0 Reply 12, posted (3 years 1 month 1 week 5 days ago) and read 19717 times:
Quoting pugsley (Reply 3): Quoting BD338 (Reply 1):
A real treat for the start of a 13 hour flight
Was it actuallt from the Air Con? I regulary need to mop up mess/water coming from the overhead lockers, however it is always liquid coming from a drink/water bottle that someone has left in their bag in the overhead locker.
Definitely not a bottle of water in my case, it happened in several locations around me on both sides of the aisle. Unless there happened to be several bottles of water.
Seems to be a common item depending on the humidity. Now, with the 787 promising higher humidity levels will this increase or decrease the chances of getting a quick shower or having ice rumbling in the ductwork?
Ben175 From Australia, joined Jul 2008, 631 posts, RR: 0 Reply 13, posted (3 years 1 month 1 week 5 days ago) and read 19588 times:
I had this on an SQ A330 final approach into PER only a few weeks ago. It was absolutely bizarre, clear blue skies and all of a sudden it sounded like our plane was being pelted with hail! The cabin crew told us on disembarkation it was "ice hitting the aircraft", which left everyone totally confused seeing as it was 36 degrees celsius and there wasn't a cloud in sight!
qqflyboy From United States of America, joined Oct 2003, 2221 posts, RR: 14 Reply 14, posted (3 years 1 month 1 week 4 days 23 hours ago) and read 19315 times:
This is also very common on Embraer a/c, especially the ERJs. Not only do you hear the ice rolling around, it often snows on you in the cabin as the ice makes it's way through the gasper vents. It's most often associated with humid air being super condensed and frozen, then shuffled around on/by takeoff. Inflight the humidity is gone, so the problem is only temporary.
Flight attendants sitting on the tailcone jumpseat of an MD-80 are often rained on due to moist air being condensed. The same problem also leads to what some people believe is smoke, but actually is just moisture rich air (fog) coming from the a/c system. This was especially pronounced on the A300.
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shankly From United Kingdom, joined Jan 2000, 1517 posts, RR: 1 Reply 15, posted (3 years 1 month 1 week 4 days 23 hours ago) and read 19288 times:
Remember experiencing this on a Garuda A330 in the same region a few years ago, but in the cruise.
I satisfied my curiosity at the time by convincing myself the aircraft may have been transiting through ice /drops particles ...the aircon thing hadn't occured to me, but would perhaps offer a more rational explanation.
CharlieNoble From , joined Dec 1969, posts, RR: Reply 17, posted (3 years 1 month 1 week 4 days 20 hours ago) and read 18629 times:
I recall a couple of Aeroflot flights I took in 1987 where there was quite a "fog" coming out of these air vents that ran along the windows on the side of the cabin (on the ground before takeoff). It was like something out of a horror movie. Being teenage punks weak on science and indocrinated by Cold War BS we were momentarily suspicious that the Russians might be anesthetizing us for the trip
Unfortunately I wasn't into civilian airliners at the time and didn't record which types of aircraft they were, but I do know that I flew at least one TU-154 and one IL-62 when I was over there. Couldn't possibly forget those four engines back at the tail!
solnabo From Sweden, joined Jan 2008, 837 posts, RR: 2 Reply 20, posted (3 years 1 month 1 week 4 days 19 hours ago) and read 17203 times:
When I was on A319 and the plane backed out from gate I heard the famous "barking dog" under the cabin (cargo bay)
What the hell was that sound, but reading on A.net I got it explained to me...kinda scary first time
Now the 330 have iceboxes above pax....*brrrrrr*