Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

Frost Forming In The Cabin Of Ryanair Flight

Wikiposts
Search
Tech Log The very best in practical technical discussion on the web

Frost Forming In The Cabin Of Ryanair Flight

Thread Tools
 
Search this Thread
 
Old 10th Dec 2007, 17:21
  #1 (permalink)  
BMI701EGCC
Guest
 
Posts: n/a
Frost Forming In The Cabin Of Ryanair Flight

Evening everyone,

I want to comment on the experience i had on my flight from BUD to LPL (738 flt no 4233) yesterday evening, We departed approx 20:00h local time. Our flight was delayed about 15 minutes due to two passengers being late, once the straddlers where onboard the crew shut the doors, we then started a much needed deicing procedure.

Anyway, we where about half way through our flight (-40 OAT), when i saw what i thought was a sticker on the panel just under the window line (sat centre of the right wing, behind the exit), i touched it as i was curious to what it was, it was defiantly frost forming. I glanced over to the seat in front to see if it was the same and it was, but much worse. I didn't call the FA as i wasn't sure if they're was something wrong.

As a side note, i want to thank the crew for a great landing, was extremely windy, just about managed to land the plane. great crabbing!

Hopefully someone could shed some light on this.

PS. the frost was about 2 inch by 10 inch on each panel

scott
 
Old 10th Dec 2007, 17:39
  #2 (permalink)  
 
Join Date: Oct 2004
Location: mids
Age: 59
Posts: 18
Likes: 0
Received 0 Likes on 0 Posts
Its proberly the bracket that attaches the panel to the airframe. The metal conducts the heat to the outside and chills the patch down to below freezing.
All the pax sweat and breath condenses and forms the frost.

Up the front on sometypes you have to watch putting your arm/hand anywhere near the window fittings on the unheated ones. You only do it once but it is quite possible to get a cold burn or even stick to DV window rails. And once you go through the freezing level you have cold dripping water down your arm for much of the approach.
tescoapp is offline  
Old 10th Dec 2007, 21:20
  #3 (permalink)  
BMI701EGCC
Guest
 
Posts: n/a
cheers for the clarification tescoapp, much appriciated!

scott
 
Old 11th Dec 2007, 11:25
  #4 (permalink)  
 
Join Date: Aug 2007
Location: Sawbridgeworth, Hertfordshire
Age: 45
Posts: 51
Likes: 0
Received 0 Likes on 0 Posts
Tescoapp - I ALWAYS wondered why, at the end of a FR flight, I was wet. Cheers

PS - I'm sure it applies to other operators using the same type
rasobey is offline  
Old 11th Dec 2007, 11:51
  #5 (permalink)  
 
Join Date: Oct 2004
Location: mids
Age: 59
Posts: 18
Likes: 0
Received 0 Likes on 0 Posts
To be fair its not just a feature of ryans or that aircraft type.

All aircraft will get it forming on the hull where you can't see it. Usually they have valves at the bottom of the hull which open at somepoint after landing which vents the condersate which has melted and run down into the belly.

Which is why you sometimes see patches of water under the aircraft on a dry ramp on stand.

It is quite a common question from new ramp handelers what the patches are.

Usually we wait until they have stuck thier finger in the puddle to see if its oil/fuel before we kid them on its overflow from the toilets before telling them the truth.
tescoapp is offline  
Old 11th Dec 2007, 12:33
  #6 (permalink)  
 
Join Date: May 2006
Location: Craggy Island....the west is best
Posts: 118
Likes: 0
Received 0 Likes on 0 Posts
Usually they have valves at the bottom of the hull which open at somepoint after landing which vents the condersate which has melted and run down into the belly.

REALLY???? Valves opening???? Not in any airplane I was an engineer on.
3bars is offline  
Old 11th Dec 2007, 12:49
  #7 (permalink)  
 
Join Date: Oct 2004
Location: mids
Age: 59
Posts: 18
Likes: 0
Received 0 Likes on 0 Posts
Go on then educate me how its done. You get told on your type ratings then you never think about it again.

Current type its a load of flap valves which get pushed shut when the plane pressurises then spring open again when you de-pressurise
tescoapp is offline  
Old 11th Dec 2007, 13:56
  #8 (permalink)  
 
Join Date: Dec 2007
Location: Southeast U K
Posts: 291
Likes: 0
Received 0 Likes on 0 Posts
Unhappy Ref Cabin window icing observed by someone who didn't see it before

It's a common event on freight aircraft, especially carrying fruit and flowers.
Aren't the spaces between the inner scratch panel and the outer pressure
panels supposed to be "filtered" via silica gel or some other form of drying
medium?
Storminnorm is offline  
Old 11th Dec 2007, 14:07
  #9 (permalink)  
 
Join Date: Mar 2005
Location: England
Posts: 730
Likes: 0
Received 0 Likes on 0 Posts
REALLY???? Valves opening???? Not in any airplane I was an engineer on.
All the boeings i've worked on have them. Small screw in plastic valves that are spring loaded open and shut themselves with cabin pressure.
Fargoo is offline  
Old 11th Dec 2007, 15:40
  #10 (permalink)  
 
Join Date: Apr 2004
Location: near EDDF
Posts: 775
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Fargoo
... Small screw in plastic valves that are spring loaded open and shut themselves with cabin pressure.
B737:
IFixPlanes is offline  
Old 11th Dec 2007, 17:21
  #11 (permalink)  
BMI701EGCC
Guest
 
Posts: n/a
cheers guys for the replies, great depth.
 
Old 11th Dec 2007, 17:57
  #12 (permalink)  
 
Join Date: Jan 2005
Location: France
Posts: 2,315
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Storminnorm
Aren't the spaces between the inner scratch panel and the outer pressure panels supposed to be "filtered" via silica gel or some other form of drying medium?
Yes, although they don't necessarily use silica gel!
This discussion is about condensation > frost inside the cabin itself.
ChristiaanJ is offline  
Old 13th Dec 2007, 00:24
  #13 (permalink)  
 
Join Date: Jul 2002
Location: brisbane, Australia
Posts: 368
Likes: 0
Received 0 Likes on 0 Posts
Smile

Thanks IFixPlanes.I'm trying to decide which model 737 you have displayed.First thought was a 100 but didn't think any-one else was as old as me !!! BTW usually closed around 1.5 psid..
fruitloop is offline  
Old 13th Dec 2007, 02:10
  #14 (permalink)  
 
Join Date: Apr 2004
Location: near EDDF
Posts: 775
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by fruitloop
...I'm trying to decide which model 737 you have displayed. ...
It is an overview out of 737CL AMM (51-41-00 Page 2)

Originally Posted by fruitloop
...BTW usually closed around 1.5 psid ...
AMM 21-00-05 Page 103 (AIRPLANE/STRUCTURE AIR LEAKAGE)
BTW : it is helpful to read fact before nitpicking
IFixPlanes is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.