Cabin Temperature
Aug 21, 2015, 9:54 am
#16
Join Date: Sep 2000
Location: OGG, YYC
Programs: AA, AC
Posts: 3,697
That's exactly what I do and in most instances it completely solves the problem.
Usually they don't have extras and occasionally they completely forget to board blankets.
No way. At all costs I want to avoid visiting that little room that has a pool of urine on the floor.
They never seem to have Grey Goose.
Get another blanket?
Ask for a warm beverage?
Vodka?
Aug 21, 2015, 10:01 am
#17
Join Date: Apr 2011
Location: YXU
Programs: AC SE100K, National E/E, HH Diamond, IHG Diamond, MB, Avis PC
Posts: 971
Actually, it doesn't. On every aircraft using bleed air (everything except the 787) the air has to be cooled, as the bleed air temperature is around 200C. I don't think anyone would want this to be blown into the cabin. And AFAIK the compressed air in the 787 has to be cooled too.
Aug 21, 2015, 10:17 am
#18
FlyerTalk Evangelist
Join Date: Jun 2003
Location: YYC
Posts: 23,808
Actually, it doesn't. On every aircraft using bleed air (everything except the 787) the air has to be cooled, as the bleed air temperature is around 200C. I don't think anyone would want this to be blown into the cabin. And AFAIK the compressed air in the 787 has to be cooled too.
You may well be right that air needs cooling. It is easy to check. First we would need to go look at the standard atmosphere table, then look at the temperature increase that results from adiabatic compression etc. I'll let someone else do the exercise.
Aug 21, 2015, 10:26 am
#20
Join Date: Apr 2011
Location: YEG
Posts: 3,717
Should not make a big difference between bleed air or air from a compressor. In both instances, roughly, consider adiabatic compression.
You may well be right that air needs cooling. It is easy to check. First we would need to go look at the standard atmosphere table, then look at the temperature increase that results from adiabatic compression etc. I'll let someone else do the exercise.
You may well be right that air needs cooling. It is easy to check. First we would need to go look at the standard atmosphere table, then look at the temperature increase that results from adiabatic compression etc. I'll let someone else do the exercise.
Aug 21, 2015, 10:35 am
#21
Suspended
Join Date: Mar 2013
Location: YVR
Programs: AC SE*2MM. SPG Plat life
Posts: 4,644
You would not wanted to be on my Westjet flight from Las Vegas on Wed. night. Cabin was over 30C for the first 2 hours. Flight landed with a temp. of 25C.
Aug 21, 2015, 10:39 am
#22
FlyerTalk Evangelist
Join Date: Jun 2003
Location: YYC
Posts: 23,808
But seriously, I would not expect that to be terribly signif9icant in comparison with the effect of adiabatic compression.
Admittedly I did not try to work out figures. To start with, one would need data on how well the cabin is insulated.
Aug 21, 2015, 10:44 am
#23
Join Date: Sep 2000
Location: OGG, YYC
Programs: AA, AC
Posts: 3,697
Aug 21, 2015, 10:53 am
#24
FlyerTalk Evangelist
Join Date: Jun 2003
Location: YYC
Posts: 23,808
BTW, I quickly worked out the figures.
Assuming at 11,000 m, conditions to be 217K and 22.6 kPa. Pressurization to 2000 m (might be a bit too high), where pressure is 79.5 kPa. Adiabatic compression for an ideal gas with gamma of 1.4 results in a temperature of around 311 K, i.e. 38C. Now, if compression is not quite ideal, and if pressurization is to an altitude a bit below 2000 m, temperature will end up a bit higher.
If using bleed air, I wonder if it might not end up being taken from some compressor stage at a pressure higher than really needed for the cabin?
Aug 21, 2015, 11:01 am
#25
Join Date: Jan 2009
Location: YOW
Programs: AC-SE100K, AC-3MM, Marriott- LT Titanium, SPG RIP
Posts: 2,959
Yes- Just a few weeks ago- TK4 from JFK to IST in J...Cabin was uncomfortably warm...and I was in shorts and a t-shirt for the sleeping portion..
Last edited by Plumber; Aug 21, 2015 at 11:01 am Reason: Spelling ...er...typing!
Aug 21, 2015, 11:16 am
#26
Join Date: Sep 2000
Location: OGG, YYC
Programs: AA, AC
Posts: 3,697
Precisely.
BTW, I quickly worked out the figures.
Assuming at 11,000 m, conditions to be 217K and 22.6 kPa. Pressurization to 2000 m (might be a bit too high), where pressure is 79.5 kPa. Adiabatic compression for an ideal gas with gamma of 1.4 results in a temperature of around 311 K, i.e. 38C. Now, if compression is not quite ideal, and if pressurization is to an altitude a bit below 2000 m, temperature will end up a bit higher.
BTW, I quickly worked out the figures.
Assuming at 11,000 m, conditions to be 217K and 22.6 kPa. Pressurization to 2000 m (might be a bit too high), where pressure is 79.5 kPa. Adiabatic compression for an ideal gas with gamma of 1.4 results in a temperature of around 311 K, i.e. 38C. Now, if compression is not quite ideal, and if pressurization is to an altitude a bit below 2000 m, temperature will end up a bit higher.
Are you an engineer??
If using bleed air, I wonder if it might not end up being taken from some compressor stage at a pressure higher than really needed for the cabin?
Aug 21, 2015, 11:48 am
#27
A FlyerTalk Posting Legend
Join Date: Sep 2012
Location: SFO
Programs: AC SE MM, BA Gold, SQ Silver, Bonvoy Tit LTG, Hyatt Glob, HH Diamond
Posts: 44,354
If I were ever in a situation where the SD said "no, other people are too cold", I would say "Okay, well they can put on another layer or grab a blanket, or I can take my pants off."
I've only once had to request the temperature to be lowered though, and that was on LH. The FA was rude about it the whole time. Maybe it's because the entire cabin had mentioned it.
Aug 21, 2015, 1:22 pm
#28
Original Poster
Join Date: Jun 1999
Location: YVR
Programs: ACSEMM QRGold SPGLifetimePlat FairmontPlat HyattD AMEXCenturion SerenaPlat TalkBoard Founding Member
Posts: 8,963
This is often a problem for me too (guessing >40% of overnight flights). For me, however, the temperature is almost always too low. I really don't know how this can be solved when one cabin temperature is perfectly comfortable for some and absolute torture for others.
Just out of curiosity, how did you know it was 24c?
By any chance was it an A330? It's anecdotal but any time I've found the cabin to be too warm it's an A330 and too cold on 767s -- especially window seats.
Just out of curiosity, how did you know it was 24c?
By any chance was it an A330? It's anecdotal but any time I've found the cabin to be too warm it's an A330 and too cold on 767s -- especially window seats.
Yup, A330.
Aug 21, 2015, 1:24 pm
#29
Original Poster
Join Date: Jun 1999
Location: YVR
Programs: ACSEMM QRGold SPGLifetimePlat FairmontPlat HyattD AMEXCenturion SerenaPlat TalkBoard Founding Member
Posts: 8,963