(Editor's Note: 10 March 2021 will forever go down the annals of history as the day the nation commisioned its first fully indigenous diesel engine submarine, christened as Indian Naval Ship Karanj. The submarine is under the capable command of Captain Gaurav Mehta and his crew of elite submariners. On the event of this historic day, it is pertinent to highlight the arduous lives and mental fortitude of a special breed; submariners, the Indian Navy's silent arm!)
When citizens think about submarines, they visualise a vessel with large glass windows through which one can see the beautiful ocean. Such submarines do exist but are for purely touristic purposes and dive to very shallow depths to show the marine creatures living on a reef.
There are other private deep-sea submersibles able to carry a few persons that are used for repairing underwater pipelines and cables. And lastly, there are military submarines made from alloy steel or titanium which obviously do not have any windows and spend many months under the sea. These are the real denizens of the deep. These are the weapons used by countries to strike terror in the hearts of their adversaries.

Indian Navy’s submarine operations have remained silently underwater, extremely secretive, that is why they are called the 'Silent Service'. Even hardcore of the navies of the world sailors think ‘submariners' are crazy, but they do so with great regard. Any man with the Dolphin pinned on his lapel deserves all the respect, for they are submariners; men who volunteer to lock themselves up in a windowless, cramped, steel contraption of a vessel to work tirelessly below the sea. Submarines are of generally two types. Attack submarines with conventional diesel-electric propulsion and those with nuclear propulsion.
Then there are those that carry nuclear tipped missiles called SLBMs. We have one Nuclear attack submarine Chakra in our inventory, one ballistic missile submarine SSBN Arihant and 13 conventional submarines in the Indian Navy. The diesel electric subs have diesel generators which charge the batteries and which in turn run the electric motors for propelling in the water.
Even today, submarines strike terror in any adversary's heart and compel them to spend disproportionate amounts on human and material resources to hunt them down. An average crew strength is about 70 men in a space which is roughly as big as a one bedroom flat. A total of 10 officers and about 60 men of various specializations man the submarine.
"The Indian submariner has to be very special person, highly trained and motivated as he prides himself as belonging to an elite force. He is respected for high professionalism by others within and outside the Navy."

Submarines carry a variety of underwater weapons called torpedoes, missiles, and mines. Torpedoes are like mini submarines and are weapons that run in the water and missiles are launched underwater which then fly through the air to hit the target, which could be a ship or on land. Hence before any mission the full strength of torpedoes, missiles or mines are loaded.
Since these long torpedoes must be loaded into the submarine, they are loaded from the muzzle of the very tube they are fired from. Similarly, the anti-ship or land attack missile is also stored in tubes and are nearly the same length as torpedoes. The tubes have to be kept in top condition; hence frequent maintenance needs dedicated men. Tons of ration to feed 70 men for 60 days or more is also required to be loaded for any mission which prior to sailing out.
Once these are loaded onboard, the crew is ready to sail out for the mission. The preparations on the submarine are hectic. All departments ensure that they are ready for a long war patrol. Every mission that a submarine embarks on is called a 'War Patrol'. Submarines are the most offensive instrument in any country’s arsenal. They are always armed and positioned at the mouth of the adversary’s harbours so that if a war breaks out, they will be the first responders.
With total readiness the submarine proceeds to sea leaving harbour on surface and only diving when the depths of water are safe enough to do so. This is done as close to our own coast within our own protection and fire power umbrella. All submarine movements are clandestine and with stealth making all movements in dark hours.
No one, not even the Captain, knows where the submarine is going on the mission. Deployment orders are top secret. They come in a sealed envelope which the Captain isn't allowed to open until he is already out at sea. This is done to maintain secrecy of operations. For the next several months, the submarine will be prowling the depths of the sea, its crew entirely cut off from the outside world, other than listening to the occasional news report which the submarine is equipped to receive even while operating underwater.
A look at the hard living conditions onboard makes one realise that the four most important requirements of human beings namely, water, air, food and space are either short or regulated onboard. Space onboard is very cramped. About two thirds of the internal volume of the submarine is filled with equipment, stores and machinery. Only one third is free volume used for living and breathing.
During construction of submarines preference is first given to fitment of equipment and only in the balance space available place for the operator has to be adjusted.
Strangely, there is water, water everywhere in the ocean but not a drop to drink on the submarine. Fresh water carried in tanks is always scarce and used very judiciously. There is no bathing and no shaving onboard. Water is only used for drinking and cooking. The occasional washing of face is permitted. Even though there is provision to convert sea water into potable water, this is only used as a last resort and not as a luxury. The crew uses disposable, medicated clothing, which they change once in four-days.
The raison d'être of the submarine which is its war fighting ability is the very existence of the submarine. Submarines are generally used for attacking ships, other submarines and land targets. Gathering intelligence on enemy’s naval units stealthily and without being detected is another role. They are also used for dropping commandos and for clandestine warfare and lastly, submarines can be used to drop mines in the enemy’s harbour mouth stealthily to bottle the adversary's fleet within their own harbours.
The periscope on a submarine is used to see objects when the submarine is just submerged below the water surface. Beyond this depth it runs blind on instruments like the Radar and Sonar.
Every floating object in the water has an acoustic signature. Hence when the submarine is on patrol, every acoustic noise heard in the ocean is investigated and tracked through by the Sonar. Every noise is tracked electronically with computer driven state of the art systems on digital charts or maps and assessed whether they are hostile or friendly. Submarines then carry out attacks on hostile targets.
"Even today, submarines strike terror in any adversary's heart and compel them to spend disproportionate amounts on human and material resources to hunt them down."

Life on a submarine is very hard in the cramped living conditions. There are numerous valves and pipelines pertaining to hydraulics-, high- and low-pressure air, sea water and hundreds of switches for electrical equipment. There must be about 200 km of electrical cables running in the submarine with electronics of about 3000 circuit boards.
Machinery spaces are really tightly packed with pumps, motors, engines and all types of equipment which can be remotely operated from the machinery station. The most difficult task is to undertake repairs of machinery below deck in these cramped conditions. We have a full marine engineering department headed by Marine Engineer Officer and electronics and electrical department by an Electronics & Electrical Officer.
There are about 300 lead acid wet batteries in a conventional submarine each weighing at least a ton. These batteries have to be monitored, topped up with electrolyte and looked after. The space above these batteries racks is so small that a man has to crawl above them on a trolley to access them.
Due to tightly packed equipment and paucity of space, there is a perennial danger of fire hazard as also danger of flooding as the outside pressure increases by 1 Bar for every 10 m of submarine depth. In order to keep the men always alert and trained to fight fires and flooding, training drills are frequently conducted.
There is hardly enough living space on a submarine as living quarters. Firstly, there are only two thirds the number of bunks as the crew. Hence, the crew coming off duty from a shift occupies the recently vacated bunk by the others who have just gone on duty. This is called 'Hot Bunking' system as the bunk is still warm when one occupies it. There are only two toilets for about 70 men. This puts tremendous strain on the men as regular timings for ablutions cannot be maintained.
Recreation is limited to only internal board games, cards, magazines, video movies. The same spaces used for living are also used for eating, as well as, for recreation. Even the officers Mess Room called the 'Wardroom' is used in its many avatars. Apart from serving as the dining room, it also converts into a sleeping room and when required into an operation theatre.
The kitchen or the Galley is the most important place in a submarine. Being so small, just a couple of chefs have to cook a meal for about 70 thrice a day. Food is cooked on hot plates, there is no frying permitted onboard as this would emanate fumes and cause coughing throughout the submarine, also adversely affecting the electronics. Fresh vegetables are carried onboard which last for only a few days, then dry rations, tinned rations, ready to eat meals and tetra packed food and milk are used.

The utensils in the Galley are kept in slots so that they do not slide off when the sea is rough. No chapatis are permitted to be made as besides taking too much effort it would emanate fumes which is not good in the confined spaces. The chefs are the most jovial of the lot always making new dishes, baking cakes for celebrating special days like birthdays, anniversaries of the crew members. There is absolutely no alcohol allowed to be consumed onboard. Smoking is not permitted.
The submarine carries a fully trained doctor who is also a submariner who is generally an underwater medicine specialist. He has a small two bed detention room with fully stocked medical stores. Apart from treating sick men like an outpatient procedure, he is responsible for maintaining the micro-climate onboard and escape and rescue from the submarine.
He performs the duty of a psychiatrist too and will be generally the first to smell a problem with the crew. The officers dining room can be converted into an operation theatre in a matter of minutes and can be made ready to undertake any minor surgery. An emergency appendicitis operation has been carried out on an Indian submarine.
Other health hazards are that of maintaining the composition of air that we breathe which has to be constantly regulated. The doctor monitors the micro climate and ensures that the oxygen levels are correct, the carbon dioxide and hydrogen levels do not go high. Besides there are other dangerous gases due to the presence of batteries. Intense smoke during fire and flooding can also cause a lot of harm and instant asphyxiation.
The other main affect on crew is that their circadian rhythm gets disrupted due to disorientation of not being able to see the sun. This causes loss of appetite and sleep disruptions as submarines are nocturnal machines requiring remaining awake in dark hours. The normal practice is to advance the watches by 12 hours hence, day becomes night and night becomes day. Artificially, daylight is simulated by white light and night by red lighting. Hence this is something like jet lag and takes the human body a few days to transition to and from.
Eye fatigue is known to affect those who see through the periscope. This happens due to frequent change in focus, different brightness, hazy objects and also boredom of seeing nothing.
Other psychological factors that affect submariners are inactivity with no physical exercise as more oxygen would be consumed and more carbon dioxide exhaled. Then there are long periods of boredom with short periods of intense activity with sleep deprivation for two to three days at a time. One factor that always is at the back of the mind is that there is no contact with the family, lastly the sense of higher responsibility and danger to life makes a person more careful and on the edge as the risks are too high.
The Indian submariner has to be very special person, highly trained and motivated as he prides himself as belonging to an elite force. He is respected for high professionalism by others within and outside the Navy. He is expected to have a higher pain threshold. He is mentally conditioned to remain away from his family for prolonged durations.
A submarine in the ocean scares the hell out of people because it’s very presence can deny the use of the sea to ships. The very presence of a submarine in the water strikes terror in the hearts of the adversary.
About the Author
Commodore Aspi Cawasji retired from the Indian Navy with three and a half decades of operational experience. He has been Commanding Officer of three submarines, a guided missile frigate and submarine base in addition to other important command and staff assignments. He has been awarded by the President of India, the Nao Sena Medal and Vishisht Seva Medal for distinguished service.
He is a published author on strategic issues having jointly authored a book titled “Strategic Vision 2030: Security and Development of Andaman & Nicobar Islands”. Currently, he is a visiting faculty at the New Delhi Institute of Management. He spends his time educating youth, indulges in his favourite hobby of calligraphy and is an avid vintner
(This article was first publshed in the Fauji India Magazine and has been reproduced with due permission)