Permission to come onboard
Sleek, black and rarely seen; the submarine is without doubt the most powerful weapons carrier man has ever devised, nothing comes close to it for fire power not even the mighty American aircraft carriers.
For over half a century these dark menacing machines have been prowling the depths of every ocean on earth awaiting the order that we all hope never comes.
Today they still prowl our depth but, in less numbers,, only six countries have nuclear powered submarines armed with submarine launched ballistic missiles, they are the United States, Russia, France, China, United Kingdom and the newest member India.
Each has a varying level of capability and arsenal’s and joint top of that list numerically is the United States and Russia.
Located just 40km from the D day beach Utah, is the city of Cherbourg. This city has lots of maritime and military history. In 1912 Titanic called here, on June 6th 1944, the American 4th infantry division landed on the Cherbourg peninsular and today Cherbourg houses the Le Redoutable; the first of her class and the first French built nuclear powered ballistic missile submarine and, the first ballistic missile submarine on public display.
Laid down in November 1964 and launched in March 1967, Le Redoutable was finally commissioned in December 1971 in a class of six submarines that would go on to provide France’s deterrent at sea for nearly decades.
Decommissioned in December 1991, she would be laid up until the year 2000 when she again was moved. This time to remove her reactor compartment and insert a steel plug.
Her 7,000ton bulk had to be lifted out of the water and placed inside a specially built dry dock. Today it is possible to see nearly every inch of the boat. If she had been in the water, like an iceberg, she would be partially hidden with only one third of the submarine visible.
Approaching the submarine, you get a sense of just how big this boat is, 140 meters long, 10.5 meters wide and a draught of 10 meters. You would think that that’s plenty of space for the 135 crew.
Unlike many other museums which start forward this museum starts aft. The first place you come to is the aft engineering room. Here the single GWC PKR K15 16,000shp nuclear reactor produced steam to turn the turbines and gear box, which in turn made the single seven skew bladed propeller turn to propel the boat.
With a maximum speed of around 30 knots, conditions are somewhat spacious for a submarine the tight gaps and haphazardly placed machinery gives you the sense of being in a small space.
In reality, the submarine herself would rarely move fast. Her mission was to hide in the ocean and await orders to fire her missiles on pre-determined targets, like the USA and UK. France’s President had no idea where she would be at any given time nor did the chief of naval staff. The only people who knew of her exact location were on board the submarine and even then, it was not the entire crew. The exact location was known by just four people.
The typical speed of a boomer on station is slightly above that of walking pace at around four to five knots.
At this speed the amount of noise created by the propeller is minimal, the seven blades have to turn less often than a four or five bladed propeller. The diameter of the propeller is also important. The screw on Le Redoutable is some 30 feet across meaning to achieve four or five knots the screw would turn at around 45 revolutions per minute.
Why do they go so slowly?
The deeper a submarine goes the less risk it has of a phenomenon called cavitation. This is where the blade is spinning so fast that it creates low pressure around the edges and tips which causes the surrounding water to boil. The bursting of the oxygen bubbles given off by the boiling water creates sound and it also damages (minutely) the propeller blades. Importantly, this phenomenon leaves a trail in the ocean that can last for hours or even days and cavitation can be heard thousands of miles away.
An example of this is when a Russian alfa class submarine was detected coming off the North Cape at forty knots heading for the Atlantic Ocean. Her noise trail was detected in Bermuda.
Cavitation usually occurs in the shallower depths when running at higher speed and with the increase in atmospheric pressure from diving deeper the risk reduces. The equation is for every ten meters you dive you increase the pressure by one atmosphere.
Looking back (as in the picture) you get a real idea that this is probably what a torpedo will hit first or at least underneath if it’s wake homing. This compartment at the time of taking the picture had only around four people in it, but the area itself when operational could hold as many as twenty-five people, which would make this confined area feel even smaller.
Into the machinery spaces
The machinery space, home to many different and important items that keep the submarine running.
If you thought it was a bit cramped in the aft machinery compartment, the machinery space will really give you the sense of being squashed and enclosed.
In this compartment we can see the osmosis and electrolysis plants as well as back up diesel engines. The osmosis plant would provide fresh water from sea water for the crew to wash, cook and drink.
Another key element is the electrolysis plant as it is in these that oxygen is made from sea water by passing an electrical charge through the water and separating the hydrogen molecules from the oxygen molecules (reverse osmosis). The excess hydrogen is then dumped overboard while the oxygen is circulated around the boat. When measured for particulate matter it turns out the air on a nuclear submarine is much cleaner than the air we breathe on the street, due to its low pollutant levels.
One of the most impressive features of a nuclear submarine is the fact it can remain submerged for months at a time; limited only by its food supply, the entire mission will be made completely independent of the surface and may last anywhere from a few days to six or seven months. The reason it can do this is because the nuclear reactor produces so much power it can power the osmosis plants and electrolysis equipment as well as the entire boat on a daily basis (this is known as the hotel load). In fact, the single nuclear reactor gives out enough energy to power a small town (they have in Russia in the 1990’s).
The engineering command station, where every mechanical object vital for the operation of the ship is controlled. This control room oversees everything from the submarines speed to the amount of power the egg whisk has in the galley.
Moving forward you enter a blank open void, which is particularly handy if you’re uncomfortable in confined spaces. You can catch your breath here while a film is playing on the bulkhead showing how they turned the boat into a museum. Incidentally, where we are standing used to be where the nuclear reactor once was prior to its removal because after all it is still classified top secret.
Another pertinent reason for its complete removal of course is that it contained many kilos of spent uranium fuel which is radioactive. This compartment would normally be off limits for most of the crew in an active submarine, but for tourists, this is biggest section of open space on the entire submarine (as a museum ship).
The Missile compartment
Before you know it, you’re stood in the compartment that is the entire reason for this boats existence. Spanning three decks and the outer deck casing these white cylinders (sixteen in total) once housed a weapon of awesome power.
This is the missile section. Here a crew of specialists would care for their deadly cargo 24 hours a day, 7 days a week, checking and re-checking every few hours ensuring that France had a ready and capable retaliation weapon. This area made me stop and think about the awesome fire power in this one craft and the sheer destructive capability it had.
Like most SSBN’s she could fire her missiles under water at a depth of around 45 meters using vapors and gas from a pre-burn motor. The missile would leave the tube and never get wet, as it breaches the surface, a sensor detects the fall of the rocket and ignites the first stage.
Into the Central command post
Entering the nerve center of the submarine or the central command post, It is here where the Captain and XO will take all decisions for the submarine.
This is the place where they would control or fight the ship. Not only do they steer the ship but also navigate, listen out for other contacts using passive Sonar, they make all the tactical decisions during an operation using all the data from the sonar system and other sensors dotted around the control room.
Navigating
How do you work out how far you can go in a set time while at sea? Well here is a basic rule set for you often used for dead reckoning.
The 3 and 6 Minute Rules
A Nautical Mile (NM) = 2000 yards (yds)
Additionally, 1 knot (kt) = 1 NM / hr = 2000 yds/hr (this is the equivalent to
MPH)
3 Minute Rule:
Speed (kts) * 100 = Distance (yds) traveled in 3 minutes
Example: if traveling 20 knots, the distance you’ve traveled in 3 minutes is
as follows:
20kts *100 = 2000yds
for 15 knots, 15kts * 100 = 1500yds
MOVE THE DECIMAL TO THE RIGHT TWO PLACES – ANSWER IS IN YARDS
6 Minute Rule:
Speed (kts) / 10 = Distance (NM) traveled in 6 minutes
Example: if traveling 20 knots, the distance you’ve traveled in 6 minutes is
as follows:
20kts / 10 = 2NM
for 15 knots: 15kts / 10 = 1.5NM
Don’t forget to move the decimal one place to the left
The crew quarters
spread over two decks with the plush officer’s mess being below and the cramped regular crew quarters above. It is also here where you would gather to eat your meals, socialize, attend church or maybe watch a movie.
It is widely known that the submarine service of any navy has the best food but is it any wonder being stuck at the bottom of the sea for months at a time? Would you do it?
Forward and finish
Reaching the torpedo room your as far forward as you can go inside the boat.
Le Redoutable is not like her smaller cousins the attack boats, she doesn’t look for trouble, instead she will hide in the deep, her torpedoes and missiles are for self-defence only because firing them will give away her position.
With tubes loaded, another dozen or so F-17 or L6 torpedoes could be carried alongside the lethal SM39 Exocet anti-ship missile.
Unlike the teardrop shape that other navies use, the hull form of Le Redoutable is rounded almost like a traditional ship. Outside you get a true sense of size and walking under her bulk you realize that this submarine is a truly incredible design.
Outside around and under
The Museum does allow you to walk around the outside of the submarine inside the dry dock, you can get some fantastic pictures from here but also you really do get a sense of the boats size.
Find out more
Visit her page at: https://museumships.us/france/le-redoutable
More pictures: https://www.flickr.com/photos/131313936@N03/albums/72157650397480829
Other works
Project 611 Zulu class
https://www.navygeneralboard.com/project-611-zulu-class-submarines/
The first soviet nuclear submarines https://www.navygeneralboard.com/the-first-soviet-nuclear-submarines/
A cold war warrior a trip through a Soviet Foxtrot class submarine
https://www.navygeneralboard.com/a-cold-war-warrior-a-walkthrough-of-a-foxtrot-class-submarine/