Major-General Raul del Rosario, military chief of plans, said the blueprint includes installing radars and sensors, and buying equipment such as submarines, frigates, fighters, surveillance planes and missile systems.
"By the time, we complete this plan, we will have complete coverage of the South China Sea," said del Rosario, a former fighter pilot, showing the military's detailed plan that was approved on Friday.
"We will have 24/7 awareness of what is happening in the disputed area and we'll be able to respond quicker to any contingency in our own exclusive economic zone."
He said the ambitious plan was initiated in 2013, but top brass had only approved overall spending of 998 billion pesos ($22.11 billion) last week.
Del Rosario said 83 billion pesos had been earmarked for the first five years, 444 billion pesos for the second five years and 471 billion pesos for the last five years.
In 1995, Congress had earmarked 364 billion pesos for a similar 15-year plan. Less than one-tenth of that sum was actually spent by 2010.
The modernization program is designed to strengthen Manila's claims in the South China Sea, believed to be rich in energy deposits.
China has become increasingly assertive in the South China Sea, building artificial islands in areas over which the Philippines and other countries have rival claims. The moves have sparked alarm regionally and in Washington.
SUBMARINES, MISSILES AND SURVEILLANCE PLANES
President Benigno Aquino has promised the military about 34 billion pesos this year, which will fund the purchase of two frigates and a twin-engine long range maritime aircraft.
So far, the government has given the military 9.4 billion pesos in 2014. This has been used to purchase eight combat utility helicopters and as a downpayment for 12 FA50 fighter-trainers from South Korea. Two of the aircraft are expected in 2016.
Del Rosario said that between 2018 and 2023 the Philippines would buy electric-diesel submarines and advanced missile systems.
Three aerial surveillance radars with a range of 350 nautical miles will also be installed in Ilocos Norte, Lubang island and Mount Salacot in Palawan, all facing the South China Sea to detect movements in the disputed area.
These will complement the navy's two surface sensors capable of detecting ship activities 200 miles away. Three surveillance planes will also be on constant patrol in the area.
"We do not aim to defeat China," del Rosario said. "But our goal is make any state think twice before attacking. We will make sure anybody attacking us would end up with a bloodied nose."
The Philippine Navy BRP Ramon Alcaraz (PF-16) with its AgustaWestland AW109 multipurpose naval helicopter.