How many submarines does the Philippines need to deter Beijing amid South China Sea row?

While the numbers may be small compared to Beijing’s, experts say these vessels play an “outsized effect” on the battlefield, as they can put other countries’ surface warships at risk and even alter an adversary’s naval strategy.

While Roy Trinidad, navy spokesman for the West Philippine Sea, did not say how many submarines Manila intended to acquire, he indicated that “definitely more than one” would be bought.

Ian Storey, a senior fellow at the ISEAS-Yusof Ishak Institute in Singapore, said the Philippines would need to acquire at least three vessels if one submarine were to be operational at all times.

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But since the Philippines has never operated submarines, Storey said the process of acquiring and integrating them would take at least a decade, as infrastructure would need to be built, including bases, piers, dry docks and other support services.

“Once delivered, it will take years of training and exercises for the Philippine Navy submariners to gain the operational experience necessary to proficiently use the boats,” Storey said.

If the Philippine placed orders for two to three submarines, it would take “at least” until the mid-2030s before they can be effectively operated, he added.

Joshua Bernard Espeña, vice-president at the International Development and Security Cooperation think tank in Manila, said two or three submarines would not be enough to deter China since the Southern Theatre Command – one of five People’s Liberation Army commands – might have more than 30 diesel-electric submarines in the South China Sea.

So the Philippines would have to ensure its small fleet “adds value” and would be able to “generate a strategic effect”