The following essay was written by a recent graduate of the Officer Training Program...
Indian Sea Lanes of Communication (SLOC): An Essay
There are a total of seven shipping routes that require India’s attention - two of them domestic, five of them international.
SLOC “W”
This route along the western coast of continental India ranges from Mumbai down to Cochin and across to Colombo on the island of Ceylon. This is a busy route for domestic trade and transportation, with hundreds of vessels at sea at any given time. Little to no foreign traffic would be expected except on direct runs into or out of the major ports - certainly not along the coast between these ports. There are no significant choke points to note, but weather hazards include the cyclone season in the southern portion of this area.
Foreign threats in this area would primarily come from submarines and mines. Light surface forces and land-based aviation from Pakistan could be a threat in the event of a conflict with the UK. The prospect of heavier surface forces or carrier aviation threatening this SLOC is doubtful as these would in turn be at risk from Indian land-based aviation and a variety of naval forces.
This region can be defended with a combination of coastal ASW and ASUW forces in tandem with land-based patrol and strike aircraft. Minesweeping forces will be required, primarily to operate around the major ports that would likely attract the most attention from enemy minelaying forces. Heavier surface forces based out of Mumbai can back the light forces in the event of an incursion by comparable enemy forces.
SLOC “E”
This eastern area of Indian maritime use ranges from the western side of Ceylon and the port of Trincomalee to Port Blair in the Andaman Islands and along the mainland at ports such as Chennai, Puri, and Sittwe. This is also a high-traffic area for domestic trade and commerce, and there is a possibility of encountering foreign ships travelling to and from Burma as well as Indian ports. The Palk Strait, separating Ceylon from India, constitutes a potential choke point for shipping, and the cyclone season presents a weather hazard that has claimed civilian and occasional military vessels in the past.
Foreign threats, apart from the ubiquitous submarine and minelaying threats, include light surface forces based out of Burma, Siam, or Indonesia, these being relevant in conflicts with Burma, Siam, and members of the AANM. Heavier surface and naval aviation forces from the major naval powers remain a potent but less likely risk in home waters.
A combination of coastal and oceanic ASW and ASUW forces, in conjunction with land-based patrol and strike aircraft, can address the more likely and, for the enemy, less risky, adversaries. Minelaying forces would be needed at the major ports and in the Palk Strait. There may be merit in establishing a defensive barrier along the Sittwe - Port Blair - Trincomalee arc to attempt to keep enemy forces out of the northwestern Bay of Bengal, with lighter forces operating as required along the coast behind this barrier. Heavy anti-surface forces operating out of Chennai and Sittwe can be used to deter or counter heavy surface forces operated by the enemy. Finally, the threat of massive land-based retaliation should deter Burma from any adventures in Indian waters.
SLOC “I-1"
This sealane extends between Mumbai, on India’s west coast, and Basra, Mesopotamia, the point of export for India’s oil supplies. While India does produce a limited amount of oil domestically, most of which goes to military use, imports from the Middle East are the private sector’s source of oil. Traffic in the Persian Gulf is heavy and diverse, with tankers from numerous countries being present. Traffic density is greatest at the Strait of Hormuz between Persia and the independent Arab emirates, and decreases outside the strait.
Light surface forces belonging to any of the local nations would be a potential threat to Indian tankers, as a torpedo from an MAS boat could suffice to immolate the largest oiler. Bombing aircraft would produce a similar risk, though the local nations operate very few machines of this type. The usual submarine and mine threats exist, but present the risk of striking neutral shipping, which may backfire on the attacker much as unrestricted submarine warfare did for Germany in the previous decade. The utility of enemy carrier-based aviation and heavy surface forces is countered in the Gulf by the restricted operating area, but would be more viable along the more distal oceanic parts of the sealane between Hormuz and Mumbai.
Diplomacy is the most important weapon in protecting Indian shipping within the Persian Gulf, as India has no bases or allies in this region. It is particularly important to consider relations with the UK, which retains tight ties with several states along the Gulf. In the event of a conflict with the UK, India would almost certainly lose the ability to import oil from Mesopotamia within weeks.
Militarily, the oceanic portions of the sealane are best defended by ocean-going ASW and general purpose escort forces, with support from seaplane carriers and patrol vessels equipped with a few such aircraft. The more likely surface threats here - armed merchantmen and cruisers - can be addressed through Indian cruisers or gunships.
SLOC “I-2"
This route originates at the western ports of Mumbai and Cochin and extends south of Arabia, into the Red Sea, and to Suez. Apart from being the preferred route for Indian trade to and from Europe, it also sees considerable use by Indian Muslims embarking on pilgrimages to the holy cities of the Middle East. The Indian mandate of Asir lies astride this route in the Red Sea. Choke points at either end of the Red Sea - the Suez Canal and Bab al Mandab - could be exploited to shut down traffic along this lane.
In the Red Sea, two different scenarios are at play. On one hand, local independent states such as Yemen and the Kingdom of Saud possess limited light surface forces that can harass Indian shipping. These would most likely be used either in support of an attack on Asir, or to provoke a diplomatically unpopular response from India. Alternately, light and heavy surface forces, land-based aviation, and submarines are potential threats in the event of a conflict with FAR, AANM, or the UK. Most of these threats extend into the northern Indian Ocean, and the formidable Italian fortifications at Bab al Mandab can threaten much of the strait. However, a conflict with any of these nations is more likely to result from some other cause, not Asir itself.
A reasonable complement of light anti-surface and general-purpose escort forces - MTBs, anti-submarine launches, and sloops - should suffice to counter any local threats. Asir could be made a costly objective for a hostile UK, AANM, or FAR through the deployment of coastal submarines, mine warfare forces, and patrol and strike aircraft. However, these potential adversaries have larger forces available than India, and they are closer to the area as well. Even if Asir were to hold out against such a threat, it is expected that the UK, AANM, or FAR would settle for cutting off Indian shipping through the Red Sea, which they could accomplish with relative ease as India concentrated efforts on core needs.
Defence of oceanic shipping between Bab al Mandab and India can be dealt with in much the same manner as that between the Strait of Hormuz and India.
SLOC “I-3"
This SLOC is a rather wide corridor, with a northward Mumbai/Cochin - Male - Victoria line and a Colombo/Cochin - Male - Diego Garcia - Port Louis as a southern route. Two-way traffic carries a variety of goods to our close ally, South Africa (textiles, tea, colored gemstones, manufactured goods) and to India (strategic metals, manufactured goods). Naturally this also serves as the main line of communication with South Africa in the military sense, and India’s ability to operate militarily does in part depend on importing South African products such as armor plate and fire control optics. Few foreign vessels would follow this sea lane, but any traffic crossing the Indian Ocean will cross it too. There are no significant choke points or weather hazards to be concerned with.
Military threats are most likely to include submarine and surface raiders from major powers on the blue water portions of the route. AANM, the UK, and to a lesser degree FAR have bases in the region that could support such action.
The presence of multiple island bases belonging to India and to the SAE should make it possible to turn this route into a fairly safe transit zone under the protection of ASW and GP escorts, with land and carrier-based aviation and heavy anti-surface forces, possibly forward-based at Diego Garcia or Male. These same assets should collectively also make it possible to interdict enemy shipping passing through the SLOC, effectively cutting the Indian Ocean in half should the need arise. The recent experience with PRS Panay is an example in point.
SLOC “I-4"
The southeasterly sea lane originates at Cochin and Trincomalee and proceeds between Australia and Indonesia to points further east. This is the primary route for trade to and from the western Americas, though this is relatively minor compared to traffic on the other routes at this time. The area is busy with commercial traffic travelling in both directions, and the relatively narrow passage between Australia and Indonesia, while not a choke point, does concentrate shipping into a small area.
The Dutch, through AANM, would be best poised to threaten this sea lane with all manner of assets ranging from light coastal forces to capital units. Australia and the UK could do the same. There is a potential for minor piracy; although the area has been frequented by the well-armed Harlock pirates, India has not yet been a victim of his raids; this may change as a result of India’s participation in the destruction of Harlock’s predreadnought in September 1928.
The problem of piracy would likely be addressed by the local powers as well as India, so is unlikely to be a prolonged issue unless political corruption allows the pirates to exist. Harlock would be more of a challenge, and in the event that he did target Indian shipping, a convoy system with cruiser escort ought to suffice to deter him. Determined opposition from either AANM or Australia/the UK would, however, be enough to close this route to India - it is unlikely that India could concentrate the forces necessary to keep the route open.
SLOC “I-5"
This northeasterly route originates in the Bay of Bengal, passes by Port Blair, and leads to Singapore, Manila, and beyond. It services trade to eastern Pacific Rim nations, and is also the primary marine line of communication to India’s SATSUMA allies: the Philippines, Japan, Formosa, and Chosen. This area, particularly along the Malacca Strait, is one of the busiest sea lanes in the world.
There are a variety of threats to this sea lane, with AANM, FAR, and the UK all having territorial possessions astride it. Minor powers such as China are also capable of interdicting shipping with surface forces.
It is generally considered that this sea lane would be difficult to maintain in the event of conflict with either the UK or AANM. It might be achievable, with a convoy system, in the event of conflict with FAR. Either way, a strong general purpose, oceanic escort capability would be needed, along with heavy surface units and air support, possibly based out of the Philippines.
Analysis
In the west, the main threats to India’s sea lanes - Italy, France, and the UK - are nations that India is unlikely to be in direct conflict with. Should a conflict arise, it would be an escalation of a crisis involving India and one of these nations’ allies - or vice-versa. The consequences of losing control of these sea lanes - particularly two and three - suggests that it is not in India’s interests to cause a situation in which Italy, France, or the UK would be compelled to involved themselves. Should this become the case anyway, routing traffic south around Africa might allow limited trade to continue, but will not help with the oil situation.
In the east, the main threats to Indian sea lanes are the Netherlands, Australia, and France. The latter, again, is not a nation which India is likely to come into direct conflict with, and Australia is much the same, without most of the colonial baggage that France bears. The Netherlands is a different matter, and long-term animosity between the Dutch and India threatens both of the easterly sea lanes. Should the situation continue, it may be advisable to improve relations with Australia and develop an alternate route south around Australia in the event of a conflict with the Netherlands. The alternative is to conclude that military action to liberate Indonesia is impractical and seek to normalize relations with the Netherlands. Either move would represent a softening of India’s traditional diplomatic stance, but this may be necessary to ensure a secure future for the empire.
With respect to operational vessels, the fleet is lacking in escorts of all kinds. A combination of the following units might best serve Indian needs over the coming years:
-A coastal sloop, with an ASW focus, for work along the coast
-A general purpose oceanic sloop, with long range to traverse the extent of the longer sea lanes
-A patrol vessel equipped with a small number of seaplanes and long range, to search large sections of sealanes for potential threats, and to provide local aerial scouting to convoys or other concentrations of civilian shipping
-A seaplane carrier, perhaps a militarized version of the Palk Bay type, allowing for patrol and strike capabilities in contested areas without requiring the commitment of aircraft carriers
-An escort cruiser capable of fighting marauding cruisers and armed merchantmen to a standstill. These could double as convoy flagships and support shore bombardment missions.
None of these concepts is entirely new, examples of the first two already in service with the fleet (in some cases, converted destroyers retaining a torpedo load). The patrol vessel could be an evolution of the pathfinder concept discussed recently in certain circles, or may follow up certain South African patrol designs. There are multiple examples of seaplane carriers and escort cruisers to examine globally, but India’s exact requirements would need to be considered carefully before construction began. If budget constraints were tight, perhaps reconstruction of the older Kolkata and Colombo classes might be an alternative to purpose-built escort cruisers as these units are replaced by new construction.
Submitted by Lieutenant His Royal Highness Shrinivas Canangasundrum, 25 November 1928
Quoted
Originally posted by The Rock Doctor
Monday, September 30th 2024, 6:20am
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