Vapour Discharge from 747 at cruise altitude
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Joined: Jun 2007
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From: Ireland
Vapour Discharge from 747 at cruise altitude
What is this being discharged from the underbelly of a BA 747 ? Presumably some sort of release valve for the air con system or something like that ?
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Thread Starter
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From: Ireland
..and furthermore isn't it a little uncomfortable to know that jets passing over our heads every day are dropping the contents of their sinks with God knows what sorts of jerms etc.
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From: NI
747s ( at least prior to the -8 ) had open-to-atmosphere grey-water drains; lav and galley sink water flushed out immediately. The problem with that is that they sing like organ pipes at 500 kt.
As a result the 777 has valve-operated drains which only open when there's a certain pressure of fluid in the system. Edit: and according to a web search, the 787 has no external drains at all; all grey-water is captured in the lav tanks.
Surplus milk and beverages are disposed of via the toilets.
As a result the 777 has valve-operated drains which only open when there's a certain pressure of fluid in the system. Edit: and according to a web search, the 787 has no external drains at all; all grey-water is captured in the lav tanks.
Surplus milk and beverages are disposed of via the toilets.
Last edited by El Bunto; 2nd January 2016 at 06:32.
Joined: Sep 2009
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From: England
The long dark streaks you see on the underside of some aircraft are often from coffee poured down the drains:
Photos: Airbus A330-223 Aircraft Pictures | !!!!!!!!!!!!!!
Photos: Airbus A330-223 Aircraft Pictures | !!!!!!!!!!!!!!
Joined: Mar 2002
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From: Florida
The long dark streaks you see on the underside of some aircraft are often from coffee poured down the drains:
How do they really know its coffee?? can they tell the difference between cafe and de-cafe? inquiring minds want to know
Death Cruiser Flight Crew
Joined: Jun 2001
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From: Vaucluse, France.
I am reliably informed that the red streaks on Concorde's undersides were caused by having to pour virtually full bottles of Château Brane Cantenac, etc., down the drain at the end of each flight.
Joined: Sep 2011
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From: Heathrow
The first thing the crew seem to do after boarding an aircraft is pour stuff down sinks 
this pleases the loaders underneath the drain immensely .....but they soon cheer up once they see that the majority of the drain effluent in landing on the aforementioned crews crew bags that are waiting to be loaded in hold 5
this pleases the loaders underneath the drain immensely .....but they soon cheer up once they see that the majority of the drain effluent in landing on the aforementioned crews crew bags that are waiting to be loaded in hold 5
