View source for Engineering:Head (watercraft)

{{short description|Ship's toilet}}
[[File:Vasa-toilets-2.jpg|thumb|right|The head on the [[Engineering:Beakhead|beakhead]] of the 17th-century warship ''Vasa''. The toilets are the two square box-like structures on either side of the bowsprit. On the starboard side, there are still minor remnants of the original seat.]]
In sailing vessels, the '''head''' is the '''ship's toilet'''. The name derives from [[Engineering:Sailing ship|sailing ship]]s in which the [[Engineering:Toilet|toilet]] area for the regular [[Engineering:Sailor|sailor]]s was placed at the head or bow of the vessel.

==Design==
In sailing ships, the toilet was placed in the bow somewhat above the water line with vents or slots cut near the floor level allowing normal wave action to wash out the facility. Only the captain had a private toilet near his quarters, at the [[Engineering:Stern|stern]] of the ship in the [[Engineering:Quarter gallery|quarter gallery]].
<!-- since most vessels of the era could not sail directly into the wind, the winds came mostly across the rear of the ship, placing the head essentially downwind. -- doesn't make sense, as noted in the Talk section -->

The plans of 18th-century naval ships do not reveal the construction of toilet facilities when the ships were first built. The Journal of Aaron Thomas aboard HMS ''Lapwing'' in the Caribbean Sea in the 1790s records that a canvas tube was attached, presumably by the ship's sailmaker, to a [[Earth:Superstructure|superstructure]] beside the [[Engineering:Bowsprit|bowsprit]] near the [[Engineering:Figurehead (object)|figurehead]], ending just above the normal [[Engineering:Waterline|waterline]].

In many modern boats, the heads look similar to seated flush toilets but use a system of [[Engineering:Valve|valve]]s and [[Engineering:Pump|pump]]s that brings sea water into the toilet and pumps the waste out through the [[Engineering:Hull (watercraft)|hull]] (in place of the more normal [[Engineering:Cistern|cistern]] and [[Engineering:Trap (plumbing)|plumbing trap]]) to a drain. In small boats the pump is often hand operated. The cleaning mechanism is easily blocked if too much [[Engineering:Toilet paper|toilet paper]] or other fibrous material is put down the pan.

[[Engineering:Submarine|Submarine]] heads face the problem that at greater depths higher water pressure makes it harder to pump the waste out through the hull. As a result, early systems could be complicated, with the head fitted to the United States Navy S-class submarine being described as almost taking an engineer to operate.<ref name=JN28 /> Making a mistake resulted in waste or seawater being forcibly expelled back into the hull of the submarine.<ref name=JN28 >{{cite book |title=U.S. subs down under Brisbane, 1942-1945 |last= Jones |first=David |author2=Peter Nunan |year=2004 |publisher=Naval Institute Press |isbn=1-59114-644-5 |pages=28–29}}</ref> This caused the loss of {{GS|U-1206}}.

The toilet on the [[Social:World War I|World War I]] [[Engineering:British E-class submarine|British E-class submarine]] was considered so poor by the captain of {{HMS|E35}} that he preferred the crew to wait to relieve themselves until the submarine surfaced at night.<ref name=Mackay88 /> As a result, many submarines only used the heads as an extra storage space for provisions.<ref name=Mackay88>{{cite book |title= Precarious Existence British Submariners in World War One |last= Mackay |first= Richard |year= 2003 |publisher= Periscope Publishing Ltd |isbn= 1-904381-17-0 |page=88}}</ref>

Aboard sailing ships and during the era when all hands aboard a vessel were men, the heads received most of their use for defecation; for routine urination, however, a pissdale was easier to access and simpler to use.

<gallery mode=packed>
File:Heads on HMS alliance.jpg|Head in British submarine {{HMS|Alliance|P417|6}} (c.1945–1973)
File:FoxTrot 480 0071.JPG|Head in Soviet submarine of the {{sclass2|Foxtrot|submarine|4}} (c.1957–1983)
File:USS Growler - Toilet (7181617746).jpg|Head in submarine {{nowrap|{{USS|Growler|SSG-577|6}}}} (mid-1950s)
</gallery>

==References==
{{reflist}}

{{Sailing ship elements}}
{{Toilets}}

[[Category:Toilets]]

{{Sourceattribution|Head (watercraft)}}