About Air craft toilets. Even with multi toilets either front or back the blue fluid all comes out of one tank each front and back. So if the tank springs a leak ----------- !!!. What is worse if the leak does not happen at the service outlet but it leaks into the plane Not good at all as the fluid is or at least used to be corrosive. EAL had a L-1011 that front tank leaked into lower electrical compartment and then into the nose landing gear compartment. When the plane put landing gear down over lake Renton Washington the frozen glob came down into the water and Seattle 911 got several reports of a body falling off airplane into the lake.
Aircraft toilets 101
The older planes had an electric pump that flushed the blue fluid around the bowl - the metal bowl was of stainless steel therefore non staining
The typical recharge of blue fluid that goes into the aircraft blue room is composed of chemicals that turn ugly green when enough urine has
been mixed and the smell gets much worse without routine maintenance:
That Maintenance involves driving or pushing a de-germ wagon up to the aircraft - small planes have one service hatch - larger ones one - forward
somewhere on the external sheet metal fuselage and one aft.
The hatch is opened and hose is connected tightly to a fitting sealing the flow of the de-germ -
A valve handle is then pulled releasing the reservoir of the used fluid into the de-germ vehicle -
The handle is shut - and a small hose with new fluid is hooked up to a valve and filled -
NOW for cheap skate airlines that is it disconnect the hoses close the hatch and move on -
The real operation is fill the toilet again and then pull the valve handle again draining new fluid and any remaining particles into the holding tank -
Close the valve and disconnect the drain hose -
Then refill with the required amount of fluid that particular aircraft requires -
Disconnect the the filling hose and close and latch the hatch
ANY QUESTIONS - Seriously this job is important and NOT DONE IN A HURRY least one avoid have a blue bath
The newer planes have the same toilet system that is found on cruise ships - a vacuum flush using much less fluid -
AND CAN BE TEMPERMENTAL JUST LIKE THE CRUISE SHIPS WITH THE WRONG THINGS FLUSHED diapers paper towels napkins and pads !
Depending on the aircraft there maybe only one service point to a central reservoir - smaller planes only one - wide body large planes
having two separate systems so at least one is available
The change of fluid is only one part of the servicing - spiffing refreshing up the interior of the blue room top side is the other part.
The blue de-germ pin stripes on the side of the fuselage is due to a bad seals on the hatch covers -
Too much fluid collecting will ice up and chunk off falling to earth some harmlessly and others with amazing concern (i.e. body parts LOL !)
One of my 99 hat job changes working a small airline station was to service the overnight aircraft - and turn around aircraft needing
urgent care - oh and blue de-germ pin stripes wash off with a little elbow grease.