Cruise ship fantails - a purpose?

[fridayeyes]

Odd question for you all. I was just looking at pictures of the Titanic and noting that today's ships don't have a series of smokestacks anymore. What they do have is that cone-shaped fantail or funnel thing about two-thirds of the way back. On Carnival, the shape reminds me of an aileron or a spoiler on the back of a sports car.

 

On a car, the supposed purpose of this is to counter any aerodynamic 'lift' and keep the car firmly on the road. Somehow, I can't imagine a cruise ship being in any danger of 'catching air', so what is the purpose of the funnel shape? Is it just an exhaust port and Carnival's looks funny to imitate a whale tail? Would cruise ships fly off into space without one? :)

 

Enquiring minds want to know....

[bruceh4]

Years ago when the ships were STEAM ships they had multiple boilers and needed several smoke stacks to vent the smoke into the air. Now days we no longer have steam ships and all are run by diesel engines. So now days it is easy to just have one stack and run all the diesel exhausts up to that stack. The problew which arises is how to prevent the exhaust from coming back down on deck and poluting the air on deck. That is the reason you see different designs of stacks. It is in an effort to lift the exhaust high enough into the air so it does not fall back down on deck. The easy way would be to just make it very tall. But then you would have the problem of getting under bridges. The new Queen Mary 2 had various designs tried to dissapate the exhaust and still get under the bridges. In fact the clearance between the top of the stack and the bottom of the Verranzano bridge in NY is only a few feet:eek:

[lougee1043]

the titanic had 4 smokestacks --yet only 3 of them were real --the 4th was the idea of white star lines- to make the titanic look different from all the other ships that generally had 3 stacks

[dougnewmanatsea]

First, a fantail is totally different from a funnel. A fantail is the stern overhang of the ship. Originally it was "fan shaped". Today, the area where HAL's ships have their aft pools would be considered to be the fantail.

 

The funnel dispenses smoke. It is basically the ship's exhaust pipe.

 

While the first steamships had only one funnel, as ships got larger, they had multiple boiler rooms and hence multiple funnels. Ships had as many as five funnels (GREAT EASTERN of 1860) simply because they had multiple boiler rooms and hence multiple funnels.

 

Eventually, the number of funnels became associated with the quality of the ship, and hence "dummy" funnels were added to smaller vessels to make them seem larger. Also, as time went on, more powerful machinery meant that even the largest ships often didn't need that many funnels. When the OLYMPIC-class ships (of which TITANIC was one) were built, they had only three boiler rooms, but a dummy fourth funnel was added for aesthetic reasons; up until these ships were built, the largest ships had for several years all been four-stackers. The tradition was broken when a year after TITANIC, her size was surpassed by IMPERATOR was built with only three funnels (no dummies). From that point on, four-stackers became very unusual. Nonetheless, dummy funnels persisted; QUEEN MARY had only two boiler rooms but a third funnel was added. Her newer sister, QUEEN ELIZABETH, came without the dummy funnel.

 

Genuine two-stackers continued into the 1960s, along with ships which had a second dummy funnel added. By now, dummy funnels weren't being added because the number of funnels were thought to denote the quality of the ship; rather, it was often purely for aesthetic reasons as in many cases a ship with two funnels simply has a more "balanced" profile. Nonetheless, by the 1960s this was already a very traditional view, espoused by a decreasing number of shipping companies. With the exception of the very largest ships like FRANCE, MICHELANGELO, and RAFFAELLO, by the 1960s it was no longer necessary to build two-funneled ships altogether, and ships like ROTTERDAM (V) and CANBERRA emphasized their modernity by having no traditional funnels all, but rather just uptakes.

 

The 1960s was also a time for experimentation with funnel designs; ships like FRANCE, MICHELANGELO/RAFFAELLO and HAMBURG had imaginative funnel designs to dissipate smoke and soot from the upper decks.

 

Funnels made something of a comeback in the '80s; while ship designers in the '60s and '70s intentionally tried to make funnels invisible, in the 1980s they made something of a resurgance. By the 1990s, DISNEY MAGIC and DISNEY WONDER became the first ships in ages to have a second dummy funnel added, to aid in their retro appearance. (There were even considerations to give them two dummy funnels for a total of three - not unprecedented as some pre-war ships like QUEEN OF BERMUDA had been built with one real and two dummy funnels.) There were considerations to give QUEEN MARY 2 dummy funnels as well, but ultimately a single modern funnel was decided upon. ZUIDERDAM in 2002 became the first ship since RAFFAELLO to have two actual, working funnels in a fore-and-aft orientation, even though they are right up against each other. These days, many large ships once again have multiple engine rooms; the number of diesel generators in a diesel-electric plant may be divided among two engine rooms in different fire zones so that a fire in one engine room would not require the ship to lose power. This is the case with ZUIDERDAM and the other Vista- and SPIRIT-class ships. However, the choice to give her two funnels (albiet in such close proximity to each other) was a purely aesthetic one as there is no reason that the diesel uptakes could not converge to one funnel.

[fridayeyes]

Wow, how very enlightening. Thank you all so much. :)

 

Cheers,

 

Friday

[Sierrachik]

Good question, Friday. Host Doug's answer was fascinating!