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The U.S.'s $13B aircraft carrier has a toilet problem

popularmechanics.com

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Re: The U.S.'s $13B aircraft carrier has a toilet problem

#31

Post by crocodiletears »

jngreenlee wrote: post #4
synaesthesisx wrote: post #3

Earlier quoted context omitted.

Exactly. The real question is - why do the chemicals cost $400,000? This seems to be a recurring theme with U.S. expenditure - particularly within the defense sector. When you get nearly blank checks from the government it’s not uncommon for items to be “marked up” so to speak and the difference pocketed by the vendors. Granted, this kind of stuff is pervasive across all sectors/layers. “[A] McKinsey “business analys…

Why did you have to bring politics into this (Buttlegug)?

You can throw shade at a consultancy without necessarily referring to one of their alumni. McKinsey was a major player in the field long before Buttigieg was an ultrasound.

Re: The U.S.'s $13B aircraft carrier has a toilet problem

#32

Post by thawaway1837 »

hejdirk wrote: post #24
trelliscoded wrote: post #22

Earlier quoted context omitted.

Guess how much shipping is to the middle of the ocean. Go on, guess.

Surely you can stock on the thing.

Why in the world would you stock it and use up valuable space, and fuel on carrying it around the world?

Also, it surely cannot be a good idea to keep massive amounts of acid around for non essential purposes.

Re: The U.S.'s $13B aircraft carrier has a toilet problem

#33

Post by 101404 »

wmoser wrote: post #23
guidedlight wrote: post #10

What problem is solved by using aircraft-style toilets on Navy ships?

Well, the old way to do it is to use sea water flushing which leads to its own problems over the life of the ship with pipes corroding. New(ish) environmental regulations dictate that you can't just flush everything overboard anymore, it needs to be processed through a sewage plant. Despite probably being able to ignore most environmental laws, the Navy normally at least tries to abide by the current laws to be a goo…

If all that can be flushed is human waste and paper, then why not put it directly into the ocean? It's quickly and completely bio degradable (eaten by fish and micro organisms).

Re: The U.S.'s $13B aircraft carrier has a toilet problem

#34

Post by LatteLazy »

unixfg wrote: post #2

Wait, what kinda of acid and how much? $400,000 seems like a lot.

If you have to make 120m each in campaign donations to 3 senators to get the contract, plus another 40m in actual cost of research, supply and profit margin and then the navy only wants to buy 1000 units because its new and they get in trouble for buying necessary supplies instead of cool shit like torpedoes, then you sort of have to charge 400k a unit...

Re: The U.S.'s $13B aircraft carrier has a toilet problem

#35

Post by ulfw »

thawaway1837 wrote: post #32
hejdirk wrote: post #24

Earlier quoted context omitted.

Surely you can stock on the thing.

Why in the world would you stock it and use up valuable space, and fuel on carrying it around the world? Also, it surely cannot be a good idea to keep massive amounts of acid around for non essential purposes.

How is it non-essential if that's the only way to get the toilets going?

Re: The U.S.'s $13B aircraft carrier has a toilet problem

#36

Post by wmoser »

101404 wrote: post #33
wmoser wrote: post #23

Earlier quoted context omitted.

Well, the old way to do it is to use sea water flushing which leads to its own problems over the life of the ship with pipes corroding. New(ish) environmental regulations dictate that you can't just flush everything overboard anymore, it needs to be processed through a sewage plant. Despite probably being able to ignore most environmental laws, the Navy normally at least tries to abide by the current laws to be a goo…

If all that can be flushed is human waste and paper, then why not put it directly into the ocean? It's quickly and completely bio degradable (eaten by fish and micro organisms).

If the ship is at sea (>12 NM) it can be put directly into the ocean but when it comes close to land it needs to be mashed up and disinfected. Also there are some places called special sea areas that have different rules even if you are more than 12 NM. There are different rules for less then 3 NM and between 3NM and 12NM too.

Having one system for when the ship is out at sea and switching to something else causes even more engineering problems. Even if you're not processing the waste, the vacuum sewage system would still be used to collect the waste to discharge it.

MARPOL Laws: http://www.imo.org/en/about/conventions/listofconventions/pa...

https://www.dco.uscg.mil/Our-Organization/Assistant-Commanda...

Special Sea Areas: http://www.imo.org/en/OurWork/Environment/SpecialAreasUnderM...

Re: The U.S.'s $13B aircraft carrier has a toilet problem

#38

Post by dctoedt »

jonititan wrote: post #19
erpellan wrote: post #18

Earlier quoted context omitted.

Aircraft toilets always sound pretty damn loud to me. And their main reason to exist on planes is the lack of available water. Pretty sure that is not an aircraft carrier’s constraint.

Actually ships are very water constrained. Especially Nuclear as they can't risk sea water contamination to the reactor cooling.

Yes, fresh water is a valuable commodity at sea; on U.S. Navy ships, water-flushed toilets are flushed with sea water, not fresh — or at least that's the way it used to be, and I can't imagine it'd be different today. (Source: Three years' sea duty as an engineering officer in the aircraft carrier USS Enterprise, CVN-65.)

EDIT: See https://www.navy.mil/submit/display.asp?story_id=103122 for a 2017 press release describing how the Reactor Department produces fresh water aboard the aircraft carrier USS Abraham Lincoln (a Nimitz-class carrier, i.e., an old design). TL;DR: It's done with giant evaporators, that is, distilling units.

Fun fact: At sea, one of the big uses of fresh water aboard a carrier is the repeated washing down of the aircraft to reduce corrosion from the salt air.

Re: The U.S.'s $13B aircraft carrier has a toilet problem

#39

Post by mysterydip »

Reason077 wrote: post #20

“system must regularly be cleaned with ... acid solution that costs $400,000 per use.” I realise the government/military procurement process can result in higher costs than the private sector would pay, but that is beyond ridiculous.

It probably qualifies as hazmat, which has a whole slew of special handling and storage requirements and raises the cost.
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