Wing Cleaning
#1
Original Poster
Suspended
Join Date: Nov 2003
Location: Wesley Chapel, FL
Programs: American Airlines
Posts: 31,464
Wing Cleaning
yesterday as we were about to push back on our SEA-DFW flight on a 738 the pilot came on to tell us the wings needed to be rinsed off (??). Sure enough a few minutes later a de-icing truck with scissor lift pulls up and starts to spray what appears to be water. FWIW it was in the mid 50's outside.
Anyone had this happen before? Did some Canadian honkers crap on his wing?
Anyone had this happen before? Did some Canadian honkers crap on his wing?
#3



Join Date: Sep 2008
Location: Midwest USA
Programs: BA Gold, UA Silver, Marriott TIT (LT), Hilton DIA
Posts: 2,033
The plane gets cold-soaked at altitude, and picks up moisture on the descent. It freezes to the wings. Even though it is in the 50's on the ground, the ice/frost will not melt quickly, and must be removed prior to the next departure. Now you know.
#4
Original Poster
Suspended
Join Date: Nov 2003
Location: Wesley Chapel, FL
Programs: American Airlines
Posts: 31,464
That sounds like that could be 95% of every plane that lands so why doesn't this happen often?
#5



Join Date: Sep 2008
Location: Midwest USA
Programs: BA Gold, UA Silver, Marriott TIT (LT), Hilton DIA
Posts: 2,033
planes do not always pick up moisture on the descent (fly through clouds that are high moisture). Or the amount of frost is minimal and melts quickly. Or the frost is not on critical surfaces (leading edge of wings or on tail)
#6
Original Poster
Suspended
Join Date: Nov 2003
Location: Wesley Chapel, FL
Programs: American Airlines
Posts: 31,464
I just find it amazing that for someone like me who is on a plane every week of the year this is the first time I've ever seen it. Go figure!
#8
FlyerTalk Evangelist




Join Date: Jan 2007
Location: BOS/UTH
Programs: AA LT PLT; QRPC PLT/OW EMD; Bonvoy LT Titanium
Posts: 14,582
Nah, I don't think so. So in 50 years of flying this has never happened to me, yet you describe it as a normal occurrence? I expect that the more likely explanation would be a one-off, and might include things like an inadvertent chemical/fluid/fuel spill on one of the wings, pilot noticed something when doing his/her walk-around, etc.
#9
Join Date: Jul 2010
Location: SFO
Programs: AA EXP
Posts: 5,270

I recall reading about this in Patrick Smith's "Ask the Pilot" column some time ago. It happens.
#10




Join Date: May 2004
Location: DFW-In Plano & CDG-In the 11th
Programs: DL Diamond, AA revenue negative, Bonvoy Titanium +, Avis likes me
Posts: 3,238
I did a MR on a LHR turn for EXP on Christmas Eve, with a Christmas Day return. I sat on the same plane in the same seat for both legs and had to wait on board in LHR for 45 minutes for de-icing.
The captains explanation was the same as nacosdelux's.
#11




Join Date: May 2005
Location: PHX
Programs: AA Gold, WN A+ & CP, HH Diamond, Hyatt Platinum, National Executive Elite
Posts: 3,258
Nah, I don't think so. So in 50 years of flying this has never happened to me, yet you describe it as a normal occurrence? I expect that the more likely explanation would be a one-off, and might include things like an inadvertent chemical/fluid/fuel spill on one of the wings, pilot noticed something when doing his/her walk-around, etc.
#14
Join Date: Feb 2014
Location: PHX
Programs: AA Aluminum, WN B+
Posts: 929
Here's a good, concise definition of cold soaking. Yes it's a real thing.
Edit: And here is a longer explanation. Cold soaking starts at bullet point No. 2.
Edit: And here is a longer explanation. Cold soaking starts at bullet point No. 2.
Last edited by Lost; Jan 20, 2018 at 7:37 am
#15


Join Date: Aug 2010
Location: KEWR
Programs: Marriott Platinum
Posts: 901
Cold soaked fuel going into the wing sometimes causes frost to form. It’s fairly common to see this under the wing on a pre-flight walkaround which isn’t a big deal because that doesn’t provide lift.
However, frost on the top of the wing disrupts the airflow and does reduce lift. That’s why you want that cleaned off.
However, frost on the top of the wing disrupts the airflow and does reduce lift. That’s why you want that cleaned off.



