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

equipment cooling


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

equipment cooling

Old 13th September 2008 | 16:36
  #1 (permalink)  
Thread Starter
 
Joined: Aug 2008
Posts: 4
Likes: 0
From: turkey
equipment cooling

in 737 aircraft all switches are in "normal" or "on" position when the switch is moved downward. but why are the equipment cooling switches normal position when switched upwards.
goksunkurkcu is offline  
Reply
Old 14th September 2008 | 11:07
  #2 (permalink)  
 
Joined: Jun 2004
Posts: 1,114
Likes: 2
From: Mydadsbag
Have pondered this myself but soon found unwrapping my small cheese portion more interesting. Let us know if you find out.
Mr.Buzzy is offline  
Reply
Old 14th September 2008 | 13:03
  #3 (permalink)  
 
Joined: Feb 2008
Posts: 1,342
Likes: 0
From: Wingham NSW Australia
Switch positions

Whilst it may be useful to have switch positions all "up" or "down" when a system is in the "normal" or "on" configuration it is always good practice to check that a system does what you expect it to be doing whenever a switch is actuated.
Old Fella is offline  
Reply
Old 15th September 2008 | 08:02
  #4 (permalink)  
20 Anniversary
 
Joined: Apr 2004
Posts: 775
Likes: 2
From: near EDDF
Originally Posted by goksunkurkcu
in 737 aircraft all switches are in "normal" or "on" position when the switch is moved downward...
Not in all 737.
Check cockpit layout of LH.
IFixPlanes is offline  
Reply
Old 15th September 2008 | 11:02
  #5 (permalink)  
15 Anniversary
 
Joined: Sep 2008
Aviation Qualifications: ATPL
Posts: 3,434
Likes: 1,200
From: 41S174E
it is always good practice to check that a system does what you expect it to be doing whenever a switch is actuated
.
so how do you check that the equipment cooling is operational when you make the selection?
framer is offline  
Reply
Old 15th September 2008 | 12:53
  #6 (permalink)  
 
Joined: Feb 2008
Posts: 1,342
Likes: 0
From: Wingham NSW Australia
B737 Equipment Cooling

Framer, since the B737 does not carry a F/E, and therefore I have not operated on that type, I can only rely on Boeing providing an "Equipment Cooling Failure" annunciator to alert the crew to such a failure, so it follows that if the applicable control switch was moved to the "Normal" or "On" position and the cooling fan did not operate the annunciator would illuminate. My point is that that it is inappropriate to be "flicking" switches without noting that the appropriate reaction takes place when a switch position is changed.
Old Fella is offline  
Reply
Old 15th September 2008 | 18:20
  #7 (permalink)  
 
Joined: Jan 2008
Posts: 22
Likes: 0
From: uk
Interesting photo but if you look closer all other switches are also opposite from equipment cooling switch. ie equipment cooling on selected downwards, packs on selected upwards ,seatbels on upwards etc etc....
tcas1 is offline  
Reply
Old 15th September 2008 | 20:20
  #8 (permalink)  
15 Anniversary
 
Joined: Apr 2007
Posts: 111
Likes: 0
From: Benelux
zey did it becauze zey are zgerman!
Navigator33 is offline  
Reply
Old 15th September 2008 | 22:42
  #9 (permalink)  
15 Anniversary
 
Joined: Apr 2008
Posts: 14
Likes: 0
From: scotland
off isn't an option with equipment cooling. cooling air is supplied by normal supply and exhaust fans whenever main elec power is on. in the event of a 'normal' fan failure the crew can select the failed cooling duct to the alternate fan. hence the orientation of the switches.
mr.newfy is offline  
Reply
Old 16th September 2008 | 10:05
  #10 (permalink)  
 
Joined: May 2006
Posts: 3
Likes: 0
From: Jutlandia Obscura
Did they put in the yoke upside down as well??

Very funky layout when you are used to the 'normal' one.
BAM_dk is offline  
Reply
Old 16th September 2008 | 14:23
  #11 (permalink)  
 
Joined: Jun 2005
Posts: 1,420
Likes: 1
From: AEP
Different strokes for different folks...

Remember...
xxx
You got airplanes (most USA airlines) which have overhead panel switches ON/OPERATING when they are DOWN or FORWARD... and rest of the world airlines generally ask Mr. Boeing (and former Mr. Douglas and Mr. Lockheed) to have overhead panel switches ON/OPERATING to the UP or AFT position...
xxx
The only USA airline that was doing like the rest of the world was TWA. When they merged into AA a few years ago, I am sure that AA and ex-TWA pilots were insulting each other every time they switched their landing lights ON or OFF...
xxx
What makes me laugh, are these airlines that acquire airplanes "second hand" from other airlines, with completely different "switchology" and instrument types and location, a headache when you have a fleet of "same type aircraft" which have a dozen different cockpit set-ups. On top of that, you do your initial or recurrent training in a simulator of (yet) another airline.
xxx
With PanAm, we had our original 747s... Then we had some 747s acquired second hand from American, United or Singapore. When we first sat in the cockpit, it was our joke to first say "where are the switches", and "what do we have and do not have on this bird"... before doing our cockpit set-up.
xxx
And then I had contracts with other airlines...
THEY want pilots to be STANDARDIZED...?
Why don't they standardize their airplanes as well...?
We already have to study a zillion different limitations for the same type.
xxx

Happy contrails
BelArgUSA is offline  
Reply
Old 18th September 2008 | 11:35
  #12 (permalink)  
 
Joined: Jan 2002
Posts: 960
Likes: 0
From: Brisbane, Australia
Yeah...

Cathay Pacific was notorious for opting for 'reverse' direction switches in it's fleet of classic '74s.

What a hassle they were to operate!!

Cheers...FD...

...but I guess that was inline with most other things at Cathay...
Flight Detent is offline  
Reply

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


Thread Tools
Search this Thread

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

Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.