SXDFC From United States of America, joined Dec 2007, 2005 posts, RR: 19 Posted (1 year 1 month 3 weeks 6 days 14 hours ago) and read 2586 times:
Hello All:
I have kinda asked this question before, but finally found the right way to "word it". I understand some of the newer aircraft ( 737NG) have one Lavatory Service port, and older aircraft ( 737 Classic ) have two ( 1 Front, 1 Back ). I was curious as to how many service ports are on much larger aircraft such as the 747,A340,A380,etc. Is there any cases where there are 3-5 service ports for a passenger aircraft, or any aircraft in that matter? Although it may sound odd any pictures are appreciated too. One last thing to add is that I understand the 737NG is Flush with 10 and fill with 6, anyone know if this too is the same on the much larger aircraft?
ALL views, opinions expressed are mine ONLY and are NOT representative of those shared by Southwest Airlines Co.
bassbonebobo From United States of America, joined Apr 2008, 66 posts, RR: 0 Reply 1, posted (1 year 1 month 3 weeks 6 days 14 hours ago) and read 2583 times:
The 747-400 and 777-300ER only have one lave service port. I believe that the same is true of the the A340 but I haven't dumped the lav on one.
Rule #176. Any device that can crawl across the table on medium, does not need to be brought into the office.
Tristarsteve From Sweden, joined Nov 2005, 3690 posts, RR: 34 Reply 2, posted (1 year 1 month 3 weeks 6 days 10 hours ago) and read 2549 times:
The standard for modern large aircraft is a vacuum toilet system with one, two, or three tanks at the rear, all serviced by a single connection.
There are three types of toilet system.
Type where you sit on the tank. Standard for many years on B727 737 757 (most) DC9 etc etc. This is where the tank is under the seat. Usually two service points, but some B757 have four. One extra each side fwd of the wing.
Type with one tank fwd and one rear. Each serves many toilets. Standard on Tristar. But some Tristars also had servicing points on the side fwd of the wing.
Vacuum toilets. Arrived in early eighties with B767. Standard on most aircraft designed since then.
Tanks are in the rear and all fluids vacuumed there.
Quoting SXDFC (Thread starter): Flush with 10 and fill with 6, anyone know if this too is the same on the much larger aircraft?
On a vacuum toilet system there is no need for a precharge. But most operaters put in some. We use 15 litres on all tanks.
ZANL188 From United States of America, joined Oct 2006, 3247 posts, RR: 0 Reply 4, posted (1 year 1 month 1 week 5 days 20 hours ago) and read 2019 times:
Quoting qslinger (Reply 3): What does Flush with 10 and fill with 6 mean?
3 step process:
1. Dump the contents of the tank
2. Flush the tank by filling it with 10 gal of water. Dump the water.
3. Fill the tank with 6 gal of lav fluid, usually some type of anti freeze to keep the waste from freezing in the tank at altitude.
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CitationJet From United States of America, joined Mar 2003, 2230 posts, RR: 3 Reply 5, posted (1 year 1 month 1 week 5 days 20 hours ago) and read 2008 times:
Quoting SXDFC (Thread starter): I was curious as to how many service ports are on much larger aircraft such as the 747
Boeing's document D6-58326-3 Terminal Servicing section 5 should give you some details.
go3team From United States of America, joined Mar 2004, 3266 posts, RR: 22 Reply 6, posted (1 year 1 month 1 week 5 days 18 hours ago) and read 1978 times:
seven3seven From United States of America, joined Apr 2005, 296 posts, RR: 26 Reply 7, posted (1 year 1 month 1 week 5 days 18 hours ago) and read 1969 times:
Quoting go3team (Reply 6): What are done with the contents after emptying?
They dump it in a complaining passenger's car.
My views are mine alone and are not that of any of my fellow employees, officers, or directors at my company
ZANL188 From United States of America, joined Oct 2006, 3247 posts, RR: 0 Reply 8, posted (1 year 1 month 1 week 4 days 23 hours ago) and read 1856 times:
Quoting go3team (Reply 6): What are done with the contents after emptying?
Pretty much what you'd expect.
Maybe different now due to environmental laws and so forth however as I recall... When the turd herders truck was full he took it to the sanitary sewer dump station on the airfield. Very similiar to dumping an RV waste tank.
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MD11Engineer From Germany, joined Oct 2003, 13336 posts, RR: 64 Reply 9, posted (1 year 1 month 1 week 4 days 23 hours ago) and read 1840 times:
Quoting Tristarsteve (Reply 2): On a vacuum toilet system there is no need for a precharge. But most operaters put in some. We use 15 litres on all tanks.
The precharge prevents the sh#t from sticking to the inside of the tank, making it easier to clean.
MD11Engineer From Germany, joined Oct 2003, 13336 posts, RR: 64 Reply 11, posted (1 year 1 month 1 week 3 days ago) and read 1637 times:
Look, most vacuum toilet systems are watersaving. They only use about 100 cubicentimetres of water to flush the waste away (home flushing toilets typically use 10 - 20 litres), so, besides the urine, there is very little liquid.
The precharge in the tank dilutes the waste and prevents it from being too sticky. You could as well use pure water. The blue dye and the parfume are only mixed into the water because the same mix is being used for the old "outhouse" style toilets, where you need something to cover the smell of the raw sewage you are effectively sitting on.
reins485 From United States of America, joined Jul 2005, 136 posts, RR: 0 Reply 13, posted (1 year 1 month 1 week 20 hours ago) and read 1429 times:
I was told by my dad, a retired AA pilot, that when AA started to send the 767 to LHR, the ground crew in LHR would precharge the tank system with same amount of liquid as the DC-10. Due to the new system on the 767 not needing that much fluid, there were diversions due to the tanks over flowing because the precharge being to large for the 767 tanks.
Tristarsteve From Sweden, joined Nov 2005, 3690 posts, RR: 34 Reply 15, posted (1 year 1 month 1 week 1 hour ago) and read 1337 times:
Quoting HAWK21M (Reply 14): Quoting reins485 (Reply 13):
there were diversions due to the tanks over flowing because the precharge being to large for the 767 tank
Wasn't there an overflow outlet that prevents excess filling on ground.
No.
There is an outlet where the vacuum goes out. On the ground, when the vacuum pump is running, you can smell the toilets from here.
But when the tank is full, a full sensor shuts down the system. This was a bit unreliable, so Boeing fitted a full sensor bypass button. Pushing this button which is in the rear galley allows one more flush. But if the tank was full this would pump fluid overboard so its use is not encouraged!
But it happens, and cabin crew keep pressing it, and the rear of the aircraft has a brown streak.
IFixPlanes From Germany, joined Feb 2005, 238 posts, RR: 0 Reply 17, posted (1 year 1 month 6 days 5 hours ago) and read 1229 times:
Quoting Tristarsteve (Reply 15): ... But when the tank is full, a full sensor shuts down the system. This was a bit unreliable, so Boeing fitted a full sensor bypass button. Pushing this button which is in the rear galley allows one more flush. ...
Can you tell me which airline use this option?
I did not hear from this before.
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