Ladies and gentlemen it's your friend Mike Brady from Oceanliner Designs
with a good old-fashioned no-frills video about the way Titanic worked.
For all intents and purposes Titanic was essentially a giant floating steel box designed
to ferry passengers across one of the harshest marine environments on earth; the Atlantic ocean.
In this part of the globe, temperatures can drop to as low as 3 degrees celsius
or 37 degrees fahrenheit and waves can reach the height of 10 storey buildings.
It is a harsh and cruel body of water; but how on eart h do you make passengers comfortable for
the 6 day duration of their voyage aboard your ship? Ocean liners like Titanic used
a number of methods to draw in fresh air, heat passenger cabins and rooms and even cool down
parts of the ship that needed it. Here’s how they heated and cooled the Titanic.
Now I just know one of you is going to make some kind of ‘water cooling’ joke
if I ask how they cooled the Titanic down so I’ll just pre-empt that now. But its
not entirely far off the mark. Steam and water were used in conjunction to regulate
the temperature of Titanic’s rooms to keep things comfortable for occupants.
I mentioned Titanic is a giant steel box; the ship’s hull is made of steel frames clad with
steel plating that was around an inch thick and although this sounds fairly hefty it isn’t much
when you consider on the reverse side of that steel plate is the freezing cold Atlantic ocean.
The design brief Titanic’s engineers stuck to was to make Titanic feel,
to first and second class passengers c at least, like they were staying in a hotel and not a ship.
To that end the ship had to be nice and warm even in the middle of the coolest Atlantic winter;
but its not just a question of heat. Imagine how stuffy a ship could become without fresh
air being circulated through it; the interiors of ships are cavernous spaces but with 2,200 people
living in close proximity to one another the air could fast become stale and very unpleasant.
In the days of old, sailing ships had a real problem with this; conditions for fare-paying
passengers were nothing short of horrendous, with the ship’s rotten bilge water permeating the air.
To get fresh air into the ship, shipwrights installed cowl vents. You’ve probably seen
these before; their shape is iconic. Rounded and kind of L-shaped to prevent rain water from
entering from above. Their function was really simple; you could point them into the wind and
their round intake would hopefully pick up some of the fresh air and drive it down into the ship.
They were unpowered just relying purely on the strength of the wind;
so you can imagine that sitting on a hot night in port without a gust would have been miserable.
So Titanic’s designers had a few challenges to overcome. First, they had to get good clean air
into the ship constantly. Second, they had to heat the ship’s spaces to a comfortable temperature.
Third, they had to cool some parts of the ship that naturally ran hotter. And finally,
they had to get the stale and hot air out of the ship as quickly as they were pulling in the fresh
air. Not entirely easy when your ship’s internal volume is around 45,000 gross registered tons and
divided into hundreds and hundreds of individual rooms and spaces. Here’s how they did it.
Titanic used two kinds of system to bring fresh air into the ship; powered and unpowered.
You know that back in the day ships used cowl vents and pointed them into the wind hoping
to catch a gust of fresh air; well Titanic had these too. These were useful for easily getting
air into rooms that weren’t too far away from the top deck where the cowl vent was placed.
You see these cowl vents at the stern? They drew in fresh air for the Third Class general
and smoking rooms directly below. You can tell which vents are unpowered; they usually had
little handles on the side so you could swing the vents and point them in the direction the wind was
blowing. They sat on top of this thing called a coaming and could rotate a full 360 degrees.
I can’t help but laugh but sometimes I’ve seen people arguing online about which
direction these vents faced and even critiquing people’s model kits because they put the vents
on the ‘wrong way’ but really they could be posed by the crew to catch the wind.
Cowl vents had another benefit; they could be removed and stored during rough weather. They
were made of really light steel and likely to be battered by heavy seas and big waves. The
vent could be taken away and the opening covered to prevent water from coming in.
So those were the unpowered vents; but they couldn’t work to get air into the
very deep bowels of the ship. Titanic was like a 882 foot long, 10 storey building;
it needed a lot of fresh air and the power of the wind just wouldn’t cut it.
Harland and Wolff, the Titanic’s builders, would need some mechanical help to get fresh air into
their ship. They got it in the form of the Sirocco fan. If you’ve ever looked closely at photos or
paintings of the Titanic like this brilliant piece by Ken Marschall, you’ve probably seen
all these strange-looking objects scattered around the decks. These are vents connected to electric
fans which drew huge volumes of fresh air down into the ship. The Sirocco vent was a 19th century
refinement of a 16th century invention; Sirocco is actually a brand name - so-called after a
Mediterranean wind that originates in the Sahara - and the business was established in Belfast.
It uses a kind of centrifugal fan, different to a ceiling fan you might be used to seeing
with blades sticking out from a central point. Instead it uses an impeller, a kind of wheel
with small angled blades. The impeller spins and creates negative pressure, drawing air in and
then pushing it along in another direction. In the case of the Sirocco vent, the air could be drawn
in through a vent cover and then sent down deep into the ship at a very fast rate. The impeller
in the fan was driven by a small electric motor. They were quiet, reliable and hugely effective;
Some Sirocco fans didn’t just draw air in though; they were used to extract stale air from deep
inside the Titanic’s hull. Titanic had about 64 Sirocco vents in a dazzling array of sizes
and shapes and simply put, the bigger the fan, the more air it could draw down into the ship.
This was really useful for modulating how big a fan and vent you’d need based on where the air
was needed. For example; a small individual galley would only need a single smaller cowl vent with a
tiny fan, say a 15” diameter Sirocco fan. But for the largest spaces in the ship, like the dining
saloon, the big 35” sirocco fans on the boat deck would be needed to draw in huge amounts of air.
In fact the Dining Saloon is a really interesting example of a space which needed as much fresh air
as it could get; it was all the way down on D-Deck, quite large but with a relatively low
ceiling for a room which was intended to seat hundreds of guests for dinner.
In photos you’ll notice the ship was festooned with hundreds of lights;
bulbs back then were pretty simple and they ran incredibly hot.
The dining saloon on Olympic became notoriously hot at meal times as those lights baked the people
sitting underneath them; there’s nothing more uncomfortable to wear than Edwardian formalwear
in hot weather. You can tell it must have been bad; the ships were even fitted with
small electric fans to get the air circulating. To counter this, a few heavy-duty Sirocco fans up on
the boat deck and deck houses were used to draw fresh air down and pump it throughout the room.
The Sirocco fans also drew fresh air in to circulate into passenger cabins; all cabins were
reached by trunking, long ducts which originated at the fans on deck level and, like the roots of a
great tree, reached down into the depths of the ship and branched out into individual cabins.
First class staterooms had the vents covered with decorative grills but down in third class it
was a lot more utilitarian and you could see the trunking up on the ceiling where it sat uncovered.
In first class the trunking was buried behind wood panels and decor.
Another way of getting fresh air into staterooms was to simply open a porthole; to that end Titanic
had thousands of portholes along her side. Most of these swung inwards so you’d be hoping the
wind was painting in your direction; but the ship also had a few unique types of porthole
designed specifically to direct fresh air into the cabin. Of course these were reserved almost
exclusively for first class; the Útley’company provided their patented swiveling porthole,
which didn’t open inwards but swiveled to the side meaning you could angle the glass itself out to
catch the wind and funnel it into your cabin. Remember Titanic would be moving forward at 22
knots or so - that’s a 25 mph breeze or 40 km/h. Not too bad for getting fresh air into your cabin!
But probably the most important area to get fresh air down into were the boiler rooms;
here there was no opportunity to install portholes; the boiler rooms were located far below
the waterline. The men who worked down here had to deal with the heat of their open furnaces, the
harsh physical labour involved in shoveling tons of coal and the tons of acrid coal dust kicked
up by their activities. It was nasty stuff and some pretty serious Sirocco firepower was needed.
First, the ship’s designers installed massive vent intakes called stokehold vents at the base
of Titanic’s first three funnels, one facing forward and one backward. The vent literally
ran straight down into the bottom of the ship; it was basically a vast, 10-storey deep shaft
that terminated at the lowest decks. Here they placed the boiler room’s secret weapon;
Sirocco fans, but not just any Sirocco fans. These were monstrous 55” fans which totally dwarfed the
largest 35” units up on the top decks. 8 of these 55” stokehold Sirocco fans serviced the ship’s 6
boiler rooms and drew in gallons of fresh air on a constant basis; they were driven by electric
motors which could output some 30 BHP. ,alongside 2 slightly smaller 50” units and . Because they
ran straight into the bowels of the ship, on the night of the sinking, anybody unfortunate enough
to be close by would have been drawn against the fan and pinned to its grating as water roared in
to flood the empty space inside. This happened to Charles Lightoller, Titanic’s second officer;
he was dragged underwater pinned to the stokehold vent intake and couldn’t break free. At the last
second a blast of hot air from below pushed him off the grate and he was able to swim away.
Another simple method of ventilating the machine spaces involved extracting hot air; Titanic’s
boilers and steam lines ran at enormously high temperatures into the hundreds of degrees celsius;
it meant the machine rooms and boiler rooms were constantly subject to heated air.
Fortunately, by its very molecular nature, hot air rises; Titanic’s designers harnessed this
by installing vast, empty shafts uncovered at the top so that hot air could just rise up and out of
the ship on its own. For the boiler rooms, Titanic had things called ‘Fidley grates’ installed at the
base of the funnels just behind the Stokehold intakes. These had a simple metal grate cover
on top and ran down into the boiler rooms; they could also double as an emergency escape or access
point; they had ladders which reached all the way down into the boiler rooms from the top decks. The
engine room needed a natural vent too; Titanic’s designers installed a big skylight deckhouse
between funnels 3 and 4 and a shaft that ran all the way down unimpeded into the engine room.
This too was covered in gangways and ladders and provided an easy access point for the
ship’s engineers if they didn’t want to go down through the passenger areas. In
fact the engineer’s mess was attached to the big engine room skylight deckhouse on the boat deck,
along with their own little promenade where they could stretch their legs. At the top
of the deckhouse were skylight covers which could be shut totally if the weather was bad;
but most of the time they were locked open in either the full-open position like here or propped
up in the half-open position like this to prevent rain or soot from the funnels from falling in.
A lot of lessons had been learned from Olympic; for her maiden voyage it was found that her
Sirocco fans and vents were mostly too small for their intended tasks and they were size
up on Titanic to account for this; Olympic eventually also got enlarged Sirocco fans
during her 1912 and 1913 refits but the layout and arrangement of these was always changing.
By the 1930s the layout of Olympic’s vents was almost unrecognizable to
her 1911 configuration because they were just getting bigger, and more numerous, all the time.
Now the designers were getting fresh air into their ship they had to regulate the temperature so
passengers would be comfortable; no easy task when the outside air could reach just above freezing
in winter crossings. Of course the amount of warm air being drawn into cabins was dictated by class,
but not in the way that you’d think.To warm much the air being drawn into the ship,
the designers used these things called thermotanks. Thermotanks were basically
giant radiators that used coiled pipes heated by steam to heat the air drawn over them and
The air for second and third class was referred to as ‘Hot Air’ and heated by the Thermotanks;
the fresh air was drawn in with a Sirocco fan over steam pipes within the tank that
heated the air up to about 80 degrees F or 27 degrees C. The fan then drew the hot air
through trunking and distributed it throughout the ship. The downside to this is that there
was no ability to modulate the temperature; so long as the thermotank was on, the radiator unit
was heating the air and supplying a constant stream of 27 degree air into your cabin. For
first class though, things were a bit different. Steam tubes were located
within the boiler uptake casings amd heated the air only to about 65 degrees F or 18 degrees C,
much cooler and more comfortable. Titanic was a British ship and 65 degrees was considered,
for the time, something like ‘room temperature’ is today. For Americans from states like Florida or
Southern Europeans though this just wouldn’t have cut it so plenty of electric space heaters - about
500 - were placed around the first class rooms, most noticeable on the grand staircase here. A
few of these space heaters have even been found in the Titanic's debris field still largely intact.
Most people are surprised to learn that all but one of the fireplaces on Titanic were
decorative and used electric heaters in place of a fire. The only functioning fireplace on
the ship was up in the First Class smoking room, and even then only because it was easy
to install a flue and chimney leading directly to the fourth funnel to get rid of the smoke.
Here’s a fun little detail; you might have noticed this little decorative brass trim at floor level
in rooms like the Dining Saloon and Smoking Room; it wasn’t actually decorative. This is
a grill vent cover for where the warm fresh air would enter the room from the boiler casings.
Now that the air was being warmed the designers had to keep it that way and bare steel does not
lend itself very well to keeping warm air in when the outside temperature is 3 degrees or so.
Insulation was used to protect Titanic’s first and second class passengers from the freezing
cold steel; Third class passengers weren’t so lucky, but at least their air was being
heated to 80 degrees Fahrenheit! Obviously the bare steel in the majority of first and second
class was clad with timber paneling; but first the builders installed insulation to partly dampen the
effects of the outside cold. The insulation ranged from appearing like a fibrous horsehair material
to being more like canvas cloth. In other parts of the ship though there was a different issue;
the ship’s funnels uptakes reared up high through the ship, right through passengers spaces like
cabins and the dining saloon. The uptakes carried the supperhated furnace gasses and
coal smoke up and out of the boilers to the ship’s funnels and they ran hot; made of steel plating,
the uptakes could be up to 300 degrees C, or 570 degrees F. Where the crossed into passenger spaces
they were hidden behind bulkheads and panelling of course, but very heavily insulated with cork; tons
and tons of cork. Without it providing a buffer between the uptakes and the public room walls, the
temperature would be unbearable, especially for inside staterooms. Huge slabs of cork, up to 18
inches or 45 cm thick, were installed to prevent heat from escaping out. After the Titanic sank,
a huge amount of cork could be seen floating on the surface; the ship had broken up and its likely
the cork panels were shredded during the sinking and floated free to the surface. Cork was also
used in the ship’s refrigerators to insulate the cold storage from the room-temperature outside.
So that’s how they did it; Titanic’s sirocco vents weren’t unique for the time. Liners like
Lusitania had used them years prior, but because Olympic and Titanic used more powered vents
than many other ships of the time, they could boast decks which were relatively uncluttered.
Just compare the Titanic’s boat deck with that of a German liner
just a few years older where fewer and smaller powered fans were used.
Its just another example of the clever engineering that went into construction what were then the
world’s greatest ships. Today many of the Sirocco vents survive in-place on the wreck but because
they are made of very thin steel, they are being eaten away at; just like the ship itself.